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Preparation, characterization and crystal structure of tetrakis[1-methyl-2(3H)-imidazolinethione] dimethyltin(IV) nitrate | Abstract The synthesis and characterization (IR, 1 H and 119 Sn NMR, and mass spectra) of [SnMe 2 (Hmimt) 4 ](NO 3 ) 2 (Hmimt=1-methyl-2(3 H )-imidazolinethione) are described. The crystal structure has been determined by X-ray crystallography and refined to R =0.044, using 2277 observed reflections. The compound is triclinic, space group P 1 , with a =10.733(2), b =10.008(2), c =7.594(2) A, α=110.49(3), β=104.71(3) and γ=82.60(3)°. The tin atom is octahedrally coordinated and lies on a crystallographic inversion centre. The Hmimt ligand, bound via the S atom (the mean of the two independent Sn-S distances is 2.735 A), maintains its thione form in the complex. The nitrate ions are involved in hydrogen bonding with the NH groups of the ligands. | This book highlighted the methods used for the syntheses of thiosemicarbazides. These new thiosemicarbazides and their metal complexes which have not been described in the literature previously were synthesized and investigated using different analytical and spectroscopic techniques and antibacterial properties. The thiosemicarbazide ligands and their metal complexes have been isolated and characterized by elemental analysis, thermogravimetric analysis, magnetic susceptibility measurements and spectral studies. The antimicrobial and antifungal activities of ligands and their metal complexes have also been evaluated | eng_Latn | 14,900 |
Structure of 4-Arylazo-3-methylisoxazol-5- thiones | Contrary to a recent report, 4-arylazo-3- methylisoxazol-5-thiones exist predominately as the 3 -methyl - 4-arylhydrazono-isoxazol- 5-thione tautomer. | The present invention provides a crosslinked skeleton crosslinked polyacrylonitrile or polymethacrylonitrile, the porous resin particles and preparation method for the functional group is a hydroxyl group or an amino group. Such resin is acrylonitrile or methacrylonitrile, a crosslinking agent containing two or more double bonds or two, functional group-containing monomer suspension alkenyl radical copolymerization in the presence of a porogen, to give porous polymeric resin porous polymeric resin, and then after the resulting functional groups, to give the functional group-containing porous resin of a hydroxyl group or an amino group. The solid phase synthesis resin can be used as solid phase synthesis or polypeptide carrier nucleotides. | eng_Latn | 14,901 |
Correction: Silver-mediated direct phosphorylation of benzothiazoles and thiazoles with diarylphosphine oxides | Correction for ‘Silver-mediated direct phosphorylation of benzothiazoles and thiazoles with diarylphosphine oxides’ by Hui-Jun Zhang et al., Chem. Commun., 2015, 51, 3450–3453. | Objective To design and synthesis novel triazole antifungal derivatives and study the antifungal activity.Methods All the target compounds were prepared from 1,3- difluorobenzene via click reaction;The antibacterial activities of the title compounds were determined with broth dilution method.Results Twelve compounds were synthesized and characterized by 1H NMR and MS.All the title compounds exhibited potent antifungal activities against nearly all fungi tested.Conclusion The electronic effects of the substituents affected the activity of compounds,specifically the electron- donating groups. | eng_Latn | 14,902 |
Design and structure-activity relationships of potent and selective inhibitors of undecaprenyl pyrophosphate synthase (UPPS): tetramic, tetronic acids and dihydropyridin-2-ones. | Based on a pharmacophore hypothesis substituted tetramic and tetronic acid 3-carboxamides as well as dihydropyridin-2-one-3-carboxamides were investigated as inhibitors of undecaprenyl pyrophosphate synthase (UPPS) for use as novel antimicrobial agents. Synthesis and structure-activity relationship patterns for this class of compounds are discussed. Selectivity data and antibacterial activities for selected compounds are provided. | In this paper, we extend our previous template analysis of a self-exciting Faraday disc dynamo with a linear series motor to the case of a nonlinear series motor. This introduces two additional nonlinear symmetry-breaking terms into the governing dynamo equations. We investigate the consequences for the identification of a possible template on which the unstable periodic orbits (UPOs) lie. By computing Gauss linking numbers between pairs of UPOs, we show that their values are not incompatible with those for a template for the Lorenz attractor for its classic parameter values. | eng_Latn | 14,903 |
Carbon-13 NMR study of 1-methyl-3-phenyl-4-diazo-5-benzoylamidopyrazole and other model pyrazole compounds | A 13C nmr study of a diazo, of two diazonium salts and of some other model pyrazole compounds is reported. It is found that the C-4 diazo carbon is more shielded than the normal sp2 pyrazole hybridized carbon, while its diazonium salt is more deshielded. The electron density on the C-4 of the diazopyrazole is probably due to the positive charge on the terminal nitrogen. Thus the 13C chemical shift values allowed us to understand the chemical behaviour of a compound of potential antitumor activity. | Spiro-compounds [e.g., (8), (13)] that resemble the four central rings of the antitumour agent fredericamycin A have been synthesized by methods that are based on (i) intramolecular acylation and high-pressure Diels–Alder chemistry [(5)→(8)] or (ii) radical spiro-cyclization [e.g., (11)→(13)]. | eng_Latn | 14,904 |
Color tunable phosphorescence in KY3F10:Tb3+ for x-ray or cathode-ray tubes | We report a persistent phosphor of KY3(1−x)Tb3xF10 (KY3F10:xTb3+) synthesized by solid-state reaction for x-ray or cathode-ray tubes. The phosphorescence consists of a group of blue and green emission lines originating from D53→F7J and D54→F7J transitions of Tb3+, respectively. The phosphorescent emitting color can be tuned from blue to green by gradually increasing Tb3+ concentrations, which is attributed to the enhanced D53-D54 relaxation through the cross relaxation between two Tb3+ ions, as described by of (D53,F76)-(D54,F70). The Tb3+ concentration dependent phosphorescence spectra are well simulated based on the analysis of luminescence dynamical processes using the Judd–Ofelt theory and rate equations concerning the D53 and D54 levels. The energy charge and release pattern of the phosphor are presented and a 10% decay time is 29 s. The measurement of the thermoluminescence glow curve gives convincing evidence for the traps analysis. | Process for the preparation of polyurethane prepolymers in which phenolic) one or more di- or polyisocyanates are reacted with b) at least one blocked isocyanate reactive compound of a functionality of at least 1.5 to give a polyurethane prepolymer of NCO-functional and then the free NCO groups are blocked with c) at least one hydrocarbon resin having phenolic OH groups d) in the presence of a catalyst containing at least one triorganoamina of the following types: i) compounds of general formula ( I) ** (See formula) ** wherein R1 is an alkyl C1-C30 optionally branched, X is O, S or N-R1 group and n is 0 or 1, ii) compounds selected from the group consisting of N, N-dimethyldodecylamine, N, N-dimethylundecylamine, N, N, N '', N '' - tetramethylethylenediamine, N, N, N '', N '' - tetramethylhexamethylenediamine, N, N, N '', N '', N '' - pentamethyldiethylenetriamine or N, N-dimethylcyclohexylamine. | eng_Latn | 14,905 |
Catalytic hydrogenation of 2,5-bis(p-nitrophenyl)pyrimidine | We have studied the catalytic hydrogenation of 2,5-bis(p-nitrophenyl)pyrimidine over palladium on carbon under different conditions. We have established that hydrogenation in acetic acid at atmospheric hydrogen pressure leads to formation of 2,5-bis(p-aminophenyl)-1,4,5,6-tetrahydropyrimidine. Upon hydrogenation under pressure in DMF, along with 2,5-bis(p-aminophenyl)pyrimidiine, three isomeric (aminophenyl)pyrimidyl-substituted benzenes are formed as by-products. The mixture of these arylazo derivatives can be smoothly reduced by hydrogen under pressure in the presence of Raney nickel to bis(aminophenyl)pyrimidine. | A ring-expanded bryostatin analogue was synthesized by utilizing a Ru-catalyzed tandem tetrahydropyran formation, a Pd-catalyzed tandem dihydropyran formation, and a ring-closing metathesis (RCM) as key steps. The analogue possesses potent antitumor activity against the NCI-ADR cancer cell line with an IC50 of 123 nM. | eng_Latn | 14,906 |
Dibenzylbis(naphthalene-2-thiolato-κS)tin(IV) | In the crystal structure of the title compound, [Sn(C7H7)2(C10H7S)2], the distorted tetrahedral coordination around the Sn atom consists of two benzyl C atoms and two S atoms of naphthalenethiolate groups. The bond angles in the coordination environment are in the range 102.27 (5)–116.63 (19)°. The average Sn—C and Sn—S bond lengths are 2.151 (4) and 2.4172 (13) A, respectively. One of the naphthalenethiolate groups is disordered, with a relative occupancy ratio of 0.726 (8):0.274 (8). | Use: in medicine as an antiallergic agent. SUMMARY OF THE INVENTION: 2-derivatives of formula aminopirimi- dinonyl TTA VN NR 6 N-L 3 wherein L - AI Az - Az - A4 - bivalent radical of formula -CH CH-CH-CH-; -N CH-CH-CH-; -CH CH-CH-N -; n 0; 1 and 2: In the group NH, CH2, O or S. Reagent 1: Compound formulyR, i N Al. N Ch-1 VCHK V (CH, CN A Reagent 2: compound of formula:. Rs-vV5 N- / WK-W, & amp; deg; The reaction conditions are: a reaction-inert solvent, base Table 4.. | vie_Latn | 14,907 |
New method for the synthesis of pyrrolo[2,3-b]dihydroquinolines | Intramolecular cyclization of [2-(2-chloroquinolin-3-yl)ethyl]amines, formed in situ from the reaction of N-phthaloyl-protected [2-(2-chloroquinolin-3-yl)ethyl]amines and hydrazine hydrate gave pyrrolo[2,3-b]dihydroquinolines in high yields. | Abstract Formation of hithertho unknown trialkylsilylated propyne derivatives 3–6 from 3-trimethylsilyl-3-ethoxycarbonylcyclopropene is described. | eng_Latn | 14,908 |
Zinc-modified hydroxyapatite coatings obtained from parascholzite alkali conversion | Abstract In this study, a novel method of zinc-substituted hydroxyapatite coating is presented. The technique consists of a two-step hydrothermal process. In the first step, the coatings consisted of parascholzite (JCPDS-01-086-2372), a mixture of parascholzite and monetite (JCPDS-01-071-1759) or parascholzite and brushite (JCPDS-72-0713), depending on the Zn concentration in the precursor solution. The second step consisted of an alkali conversion in a KOH solution. The resulting coating was identified as zinc-doped hydroxyapatite. Growing amounts of ZnO were identified for the coatings obtained with higher Zn content. Rietveld refinement revealed a slight decrease in the unit cell volume, due to zinc partial substitution, when compared to pure hydroxyapatite coatings. | During the last eight years a number of aspects of ::: amide chemistry have been studied in the Chemistry ::: Department, University of Tasmania, under the direction ::: of Dr. J. B. Polya. Acylation of amides to diacylamines ::: was investigated, and satisfactory syntheses were developed ::: for unsymmetrical diacylamines (R1 ::: .CO.NH.CO.R2; R1≠R2 ). In some cases such diacylamines, through reacylation, ::: may form mixtures of the two corresponding ::: symmetrical diacylamines. Diacylamines react with hydrazines ::: to form 1:2:4-triazoles, which are convenient ::: derivatives indicating the structure of the diacylamine. ::: With a hydrazine R.NH.NH2 an unsymmetrical diacylamine ::: of the type indicated could form 1R-3R1 -5R2 - and ::: 1R-3R2 -5R1 -1:2:4-triazole. Proving the orientations of ::: the products from a number of diacylamines seemed a ::: promising way to investigate the mechanism of this triazole ::: synthesis. | eng_Latn | 14,909 |
Studies on isomerism of 1:2 iron complexed dye based on 1-(5'-nitro-2'-hydroxyphenyl)-3-cyano-5-(4-sulphonamidophenyl)formazan | Abstract During the synthesis of previously described new 1:2 iron complexes of 1,5-diaryl-3-cyanoformazanes it was found that the metalisation process is dependent on the pH of the reaction media and in some cases two isomeric products appear. These isomers exhibited the same quantitative composition but different colours and physico-chemical properties. With the use of 1 H-NMR and IR analysis and the measurements of magnetic moments an attempt to attribute the chemical structure to both isomers of 1:2 type iron complex of 1-(5′-nitro-2′-hydroxyphenyl)-3-cyano-5-(4″-sulphonamidophenyl)formazan has been made. | Abstract The syntheses, magnetic properties, and reactions with nitrogen donors of a number of related A2[Fe2CI6 salts (A = H-TMPP, PPh4, Et4N, AsPh4, ppn) ([H-TMPP Cl = [H-P(C6H2(OMe3)3 Cl) as well as the neutral cluster Fe4CI8(THF)6 are discussed. | eng_Latn | 14,910 |
Silicon-mediated isoquinoline synthesis: preparation and stereochemical characterization of 4-hydroxy-3-phenylisoquinolines | Abstract The silicon-mediated synthesis of 4-hydroxy-6,7-dimethoxy-3-phenylisoquinoline derivatives is reported. The described procedure implies synthetically useful yields and a high degree of stereoselectivity. | Structural evolution of the quinqzoline as effective agents in the treatment of microbial infe ctions. Novel quinqzoline based thiosemicarbazide and styryl derivatives have been designed and synthesized. The structures of the synthesized compounds were assigned on the basis of elemental analysis, IR, 1H NMR. spectral data. All the newly synthesized compounds were screened against various strains of bacterial and fungi.it has been observed that compounds gave significant co-relation. | eng_Latn | 14,911 |
Method for preparing Zyprexa crystal form II | The invention discloses a method for preparing Zyprexa crystal form II. The method for preparing the Zyprexa crystal form II comprises the following steps of: dissolving a Zyprexa crude product into acetonitrile; cooling and crystallizing; washing the obtained crystal with ethyl acetate or methylbenzene; and drying to obtain the Zyprexa crystal form II. Compared with the prior art, the method has the advantages of effectively controlling residual quantity of the solvent acetonitrile and contributing to market competition, along with high purity in products. | Structural evolution of the quinqzoline as effective agents in the treatment of microbial infe ctions. Novel quinqzoline based thiosemicarbazide and styryl derivatives have been designed and synthesized. The structures of the synthesized compounds were assigned on the basis of elemental analysis, IR, 1H NMR. spectral data. All the newly synthesized compounds were screened against various strains of bacterial and fungi.it has been observed that compounds gave significant co-relation. | eng_Latn | 14,912 |
Concise syntheses of 7-anilino-indoline-N-benzenesulfonamides as antimitotic and vascular disrupting agents | Abstract Described herein is the development of a novel series of 7-anilino-indoline-N-benzenesulfonamides, derived from ABT751 ( 1 ), as potent anticancer agents. Amongst the synthesized series, compounds 6 , 12 , 13 , and 14 have shown comparable to better anticancer activity on comparing with compound 1 . 7-(4-Cyanophenylamino)-1-(4-methoxybenzenesulfonyl)indoline ( 13 ) was found to be the most potent one with up to 6 fold better activity against KB, HT29, and MKN45 cancer cell lines with IC 50 values of 49.7, 149, and 92 nM, respectively. Compound 13 was also found inhibiting multidrug resistant cancer cell lines, blocking cell cycle at G2/M phase, and inhibiting tubulin polymerization. Capillary disruption assay results revealed that compound 13 was able to disrupt formed capillaries in a concentration-dependent manner without affecting cell viability. | Abstract The intercalation of tris-bipyridyl metal complexes (M(bpy) 3 2+ , M=Ru, Ni, and Co) into the interlayer region of vanadium pentoxide gel (V 2 O 5 ·nH 2 O) was confirmed for the first time. The intercalation of the guest species was conducted by the reaction of the complexes with undried V 2 O 5 gel. The saturated amount of adsorbed M(bpy) 3 2+ was less than the ion exchange capacity of the V 2 O 5 gel because of bulkiness of M(bpy) 3 2+ . The transition temperature to orthorhombic V 2 O 5 was higher than that of original V 2 O 5 gel, indicating the stabilization of the layered structure by the intercalation. | eng_Latn | 14,913 |
Comparative analysis of the formation mechanisms of polycyclic aromatic hydrocarbons and fullerenes in flames | Various formation mechanisms of polycyclic aromatic hydrocarbons and fullerenes in benzene flames have been analyzed. It has been shown that the process of building-up of the aromatic structure of the given components in the flame includes both the addition of acetylene molecules with subsequent intramolecular restructuring and formation of new aromatic rings and coagulation in which fullerenes are assembled from different aromatic fragments. We propose an optimal model of the process providing the best agreement with the available experimental data. | Abstract The preparation and biological activity of analogs of (−)-cytisine, an α4β2 nicotinic receptor partial agonist, are discussed. All-carbon-containing phenyl ring replacements of the pyridone ring system, generated via Heck cyclization protocols, exhibited weaker affinity and lower efficacy partial agonist profiles relative to (−)-cytisine. In vivo, selected compounds exhibit lower efficacy partial agonist profiles than that of (−)-cytisine. | eng_Latn | 14,914 |
Electrochemical behavior and X-ray crystal structure of the unusual dimeric ruthenium(cyclooctadiene) complex, (tri-μ-chloro)(chloro)(acetonitrile)bis(η4-cyclooctadiene)-diruthenium(II) | Abstract A novel Ru(II)(COD) dimer containing triply-bridging chloride ligands has been prepared and its crystal structure determined. The metal atoms each contain axial COD ligands and are separated by a distance of 3.251 A. Both transition metals possess octahedral coordination geometries. One contains a coordinated molecule of acetonitrile and the other contains an axial halide ligand. Electrochemical investigations show that the complex undergoes two one-electron oxidations that satisfy the criteria for a fully reversible diffusion controlled process. An improved method of preparing this dimeric Ru(II) cycloolefin complex is also presented. The crystals are monoclinic, space group C 2/ c , a =21.258(6), b =7.179(2), c =27.068(7) A, β=93.18(2)°, V =4124(2) A 3 . Convergence to conventional R values of R =0.0368 and R w =0.0394 with a goodness-of-fit of 0.95 was obtained for 226 variable parameters and 2710 reflections with I >0σ( I ). | Abstract Bis[trinitratocerium (IV)] chromate is able to proceed oxidative deprotection of trimethylsilyl ethers in benzene under reflux conditions. Trinitratocerium(IV)chwmate dihydrate is a very sluggish oxidant for this purpose. | eng_Latn | 14,915 |
Synthesis of bis(2-hydroxybenzyl)amine and molecular structure of its sodium salt | The reduction reaction of bis(salicylidieneamino)methyl-2-phenol with potassium borohydride was studied.The product was bis(2-hydroxybenzyl)amine,not the expected bridging triphenol,due to the cleavage of a C-N bond.Sodium bis 2-oxidobenzyl ammonium was obtained by dissolving the bis(2-hydroxybenzyl)amine in a NaOH solution,and its molecular structure was elucidated by single crystal X-ray diffraction analysis. | A method was developed to reduce aromatic nitro compounds to the corresponding anilines using sulfur and base. The method tolerates a range of functional groups on the benzene ring, avoids the use of hydrogen and transition metals and provides the anilines in moderate to high yields. | eng_Latn | 14,916 |
Controlled synthesis of electron deficient nitro-1H-benzotriazoles | Nitro-1H-benzotriazole derivatives containing electron withdrawing substitutents in the ortho and meta positions to the nitro group have been synthesized by the simple and direct nitration of the parent 1H-benzotriazoles. The route of nitration and assignment of isomerism in these compounds is proposed based upon high level density functional theory (DFT) calculations. | Abstract The use of zinc tetrafluoroborate as a catalyst in Mannich-type addition of silyl enol ethers to aldimines in aqueous THF provides β-amino ketones or β-amino esters in high yields. A one-pot reaction of an aldehyde, amine and silyl enolate also works well. | eng_Latn | 14,917 |
Synthesis and antifungal activities of new triazole compounds | Objective To design and synthesis novel triazole antifungal derivatives and study the antifungal activity.Methods All the target compounds were prepared from 1,3- difluorobenzene via click reaction;The antibacterial activities of the title compounds were determined with broth dilution method.Results Twelve compounds were synthesized and characterized by 1H NMR and MS.All the title compounds exhibited potent antifungal activities against nearly all fungi tested.Conclusion The electronic effects of the substituents affected the activity of compounds,specifically the electron- donating groups. | Abstract The crystal structure of [Ni(Hbim)3](nPr4N)•MeOH (1) (Hbim− =mono- deprotonated 2,2′-biimidazolate and nPr4N+ = tetra-n-propyl-ammonium cation) has been determined. The structure was consists of Ni(II) centers hexacoordinated by three 2,2′-biimidazolate (Hbim−) ligands in an octahedral arrangement. Complex 1 possesses an intermolecular hydrogen bonding structure of zigzag one-dimensional chains in which two of the three Hbim− ligands connect the metal complex units. | eng_Latn | 14,918 |
Synthesis and Application of New Type Organometallic Catalyszt -Synthesis of Bisphosphonite-Rhodium Complexes- | The new type ligand, bisphosphonites, were easily prepared through ligand exchange reaction of bis (diethylamino)phosphine with diols. These bisphosphonites reacted with to corresponding bisphosphonite-rhodium(I) comlexes, of which X-ray crystallography was for the first time investigated. This organometallic compound was applicated in hydroformylation reaction as catalyst, and proved to be very effective one. | 2-nitroaniline (2-NA) is highly toxic and environmental contaminant. It is reduced to less toxic and environmental benign product o-phenylenediamine by using different reducing agents like sodium borohydride, potassium borohydride, or hydrazine hydrate in the presence of various catalytic systems. These catalytic systems have various advantages and drawbacks. Silica-supported gold nanoparticles are frequently reported catalyst for the reduction of 2-nitroaniline in aqueous medium. In this review article, different catalytic systems reported for reduction of o-nitroaniline under various reaction conditions have been discussed. The critical review of the recent research progress for development of novel catalysts used for the reduction of 2-nitroaniline has been provided here. | eng_Latn | 14,919 |
Experimental and computational study of 6-exo and 7-endo cyclization of aryl radicals followed by tandem S(RN)1 substitution. | The reaction of N-allyl-N-(2-halobenzyl)-acetamides and derivatives was investigated in liquid ammonia under irradiation with the nucleophiles Me3Sn(-), Ph2P(-) and O2NCH2(-). Following this procedure, novel substituted 2-acetyl-1,2,3,4-tetrahydroisoquinolines and substituted 2-acetyl-2,3,4,5-tetrahydro-1H-benzo[c]azepines were obtained in good yields. These reactions are proposed to occur through the intermediacy of aryl radicals, which by intramolecular 6-exo or 7-endo attack to a double bond cyclize to give aliphatic radicals, which react along the propagation steps of the S(RN)1 chain cycle to afford the cyclic substituted compounds as main products. The reactions were modeled with DFT methods, which provide a rational understanding that relates the product distribution to the structure of the aliphatic radicals proposed as intermediates and the kinetic of their formation. | Following a stereochemical guideline, it was possible to obtain both right and left double-helical models of DNA [l-3]. When a nucleotide unit is used as a repeat, uniform helices are obtained and they can be classified into two categories; righthanded (RU) and left-handed (LU) uniform helices (41. The stereochemical guideline for molecular model building using a nucleotide repeat was as follows. A correlation should always be maintained between the sugar conformation and the P-O torsions to obtain stereochemically satisfactory RU and LU helices [l-4]. In this way, 5 conformations of the nucleotide repeat were obtained which gave rise to RU and LU helices [4]. This deals with the extension of the stereochemical guideline and this results in two additional nucleotide conformations which again give rise to RU and LU helices. | eng_Latn | 14,920 |
Amination of benzylic C–H bonds by aryl azides catalysed by CoII(porphyrin) complexes. A new reaction leading to secondary amines and imines | CoII(porphyrin) complexes catalyse the reaction of ::: aromatic azides, ArN3, with hydrocarbons containing a benzylic ::: group, R1R2R3CH, to give the corresponding ::: amines, R1R2R3C-NHAr. When at least one of ::: the R1–R3 substituents is hydrogen, the ::: catalytic reaction proceeds further to give the imines ::: R1R2CNAr in good yields. | Abstract New aromatic polyamides from the bisamines 2,2-bis(p-amine-pheny1)-1, 1,1-trichloroethane (Bisamine I), 2,2-bis(p-amine-pheny1)-1,1-dichloroethylene (Bisamine II), and terephtaloil chloride were synthesized by means of several methods. It was found that low-temperature solvent polycondensation is optimum for obtaining polymers with the best properties, which are predominantly better in the case of polyamides based on Bisamine II. | eng_Latn | 14,921 |
Dimethylbis(pyrazine-2-carboxylato-κ2 N 1,O)tin(IV) | In the title compound, [Sn(CH3)2(C5H3N2O2)2], the SnIV atom is twice N,O-chelated by two pyrazine-2-carboxylate ligands. The distorted six-coordination is completed by two tin-bound methyl C atoms. The C2N2O2 donor set defines a skewed trapezoidal–bipyramidal geometry. Intermolecular π–π interactions between the pyrazine rings [centroid–centroid distance = 3.8112 (13) A] are observed. | FIELD: chemistry. SUBSTANCE: invention concerns process of production of diisopropyl {[1-(hydroxymethyl)-cyclopropyl]oxy}methylphosphonate represented by the formula , which is the key intermediate compound in synthesis of antiviral nucleoside analogue. The invention also concerns new intermediate compounds of formulae and , and their production of compound (2) obtained under this invention, which is an antiviral nucleoside analogue (especially against hepatitis B virus) represented by the formula . EFFECT: high purity grade and high output. 4 ex | eng_Latn | 14,922 |
Cardiovascular actions of kynuramine and 5-hydroxykynuramine in pithed rats | Kynuramines occur endogenously in brain and peripheral tissues as metabolites of indoleamino acids and indolamines but little is known regarding their possible physiological and/or pharmacological activity. The present study has investigated the effects of kynuramine and 5-hydroxykynuramine on the cardiovascular system of pithed rats and attempted to correlate effects seen on adrenergic and serotonergic receptors with ligand binding experiments donein vitro using rat brain membranes. | A practical asymmetric synthesis of the complex fused bis-macrocyclic HCV protease inhibitor MK-6325 (1) is described. Through the combination of a high yielding and low catalyst loading ring-closing metathesis (RCM) to forge the 15-membered macrocycle with an intramolecular sp(2)-sp(3) Suzuki-Miyaura cross-coupling to append the 18-membered macrocycle, multikilogram access to the unique and challenging architecture of MK-6325 (1) has been achieved. | eng_Latn | 14,923 |
ChemInform Abstract: Reversible Solid State Redox of an Octacyanometallate-Bridged Coordination Polymer by Electrochemical Ion Insertion/Extraction. | [Mn(H2O)] [Mn(HCOO)2/3(H2O)2/3]3/4 [Mo(CN)8]·H2O is precipitated by addition of an aqueous solution of Cs3[Mo(CN)8] to a HCOOH/H2O (3:1) solution of MnCl2 (92% yield). | In the syntheses of 5-oxazolones (2-isopropenyl-4-alkyl-2-oxazolin-5-ones) from N-meth-acryloyl-α-amino acids, new isomerized oxazolones were obtained. By NMR spectroscopy, the structures of isomerized oxazolones were determined to be pseudoxazolones (2-isopropylidene-4-alkyl-3-oxazolin-5-ones). The NMR spectra of several pseudoxazolones were measured and compared with the normal oxazolones. | eng_Latn | 14,924 |
The tautomeric equilibria of thio analogues of nucleic acid bases. Part 3. Ultraviolet photoelectron spectra of 2-thiouracil and its methyl derivatives | The photoelectron spectra of 2-thiouracil and four monoalkyl and four dimethyl derivatives were recorded using He(I) and He(II) excitations. The assignments of the photoelectron bands were based on relative band intensity variations, on the results of AM1 calculations, and by comparisons with uracil and its methyl derivatives. The photoelectron spectrum of 2-methyl-2-thiouracil gave evidence of two forms in tautomeric equilibrium in the gas phase. | Process for the preparation of polyurethane prepolymers in which phenolic) one or more di- or polyisocyanates are reacted with b) at least one blocked isocyanate reactive compound of a functionality of at least 1.5 to give a polyurethane prepolymer of NCO-functional and then the free NCO groups are blocked with c) at least one hydrocarbon resin having phenolic OH groups d) in the presence of a catalyst containing at least one triorganoamina of the following types: i) compounds of general formula ( I) ** (See formula) ** wherein R1 is an alkyl C1-C30 optionally branched, X is O, S or N-R1 group and n is 0 or 1, ii) compounds selected from the group consisting of N, N-dimethyldodecylamine, N, N-dimethylundecylamine, N, N, N '', N '' - tetramethylethylenediamine, N, N, N '', N '' - tetramethylhexamethylenediamine, N, N, N '', N '', N '' - pentamethyldiethylenetriamine or N, N-dimethylcyclohexylamine. | eng_Latn | 14,925 |
Diazotization–azidation of amines in water by using crosslinked poly(4-vinylpyridine)-supported azide ion | The use of polymeric reagents simplifies routine azidation of diazonium salts, because it eliminates the traditional purification. An efficient, simple, and effective method for the preparation of aryl azides is described. The synthesis of aromatic azides from the corresponding amines is accomplished under mild conditions with sodium nitrite in the presence of p-toluenesulfonic acid or concentrated H2SO4 at low temperature (0–5°C to room temperature). The obtained relatively stable diazonium salts, followed by treatment with a polymer-supported azide ion in water at room temperature to produce the corresponding aryl azides. The spent polymeric reagents can be regenerated and reused for several times without losing their activity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 | In the present investigation a series of some novel synthetic Chalcones (2a-d) and their heterocyclic analogs such as Isoxazolines (3a-d), Pyrimidines (4a-d), Pyrazolines (5a-d), Benzodiazepines (6a-d) and | eng_Latn | 14,926 |
Substituent dependence of stable conformations in triazolobenzothiazines | From the 1H and 13C NMR spectra of angularly condensed triazolobenzothiazine derivatives it was established that these compounds can be classified into two conformation types, depending on the substituents. The 10-methyl-3-carbethoxy derivatives are cis-anellated, conformationally flexible systems, where one of the aromatic hydrogens (H-9) and one of the methoxy substituents (8-OMe) of the benzothiazine skeleton on the one hand, and the 1-aryl ring on the other, lie close to each other in the preferred conformer. By assuming this conformation, the molecules avoid the steric hindrance of the 10-Me and 1-aryl groups. All compounds unsubstituted on the angular C-10 atom, and the 3-aryl-substituted derivatives of the 10-Me analogues, occur in a different conformation, containing the 1-aryl ring well removed from H-9 and the 8-OMe group. | Abstract The use of zinc tetrafluoroborate as a catalyst in Mannich-type addition of silyl enol ethers to aldimines in aqueous THF provides β-amino ketones or β-amino esters in high yields. A one-pot reaction of an aldehyde, amine and silyl enolate also works well. | eng_Latn | 14,927 |
Condensed thiophen ring systems. Part 20. Synthesis of 5-arylthieno-[3,2-b]pyrroles and 5-arylthieno[3,2-c]pyrazoles | Reductive cyclisation of the alkenes (5)–(8)(prepared by condensation of methyl 2-methyl-3-nitrothiophen-5-carboxylate with an aromatic aldehyde) with triethyl phosphite gave thieno[3,2-b]pyrroles (1)–(4). Thieno[3,2-c]pyrazoles (12)–(14) were prepared similarly from the anils (15)–(18) or the nitrones (22) and (23). Condensations between alkyl 2-methyl-3-nitrothiophen-5-carboxylates or 2-methyl-3-nitrobenzo[b]thiophen and NN-dimethyl-4-nitrosoaniline have been shown to give mixtures of nitrones [(22), (23), and (27)(major products), respectively] and the corresponding anils [(16), (17), and (26)]. A procedure is given for alkylation of 2-formyl-3-nitrothiophen-5-carboxylic acid (19) which avoids deformylation and involves formation of its sodium or potassium salt with an alkali metal hydrogen carbonate in hexamethylphosphoramide followed by addition of an alkyl iodide. | Abstract A short chemical process is described for the synthesis of optically active 3-hydroxy-4-alkoxycarbonyl-2-azetidinones (β-lactams) from L-tartaric acid. | eng_Latn | 14,928 |
N-Tosyl-1,5,2,6-dithiadiazocane: a waste-free electrophilic sulfur reagent for the efficient synthesis of medium-ring S,N-heterocycles | We report on the application of an eight-membered C2-symmetric sulfenamide derivative as a new convenient and highly reactive electrophilic sulfur–nucleophilic nitrogen synthon for the concise synthesis of medium-ring S,N-heterocyclic systems. | Chemotherapy still constitutes a basic treatment for various types of cancer. Anthracyclines are effective antineoplastic drugs that are widely used in clinical practice. Unfortunately, they are characterized by high systemic toxicity and lack of tumour selectivity. A promising way to enhance treatment effectiveness and reduce toxicity is the synthesis of systems containing anthracyclines either in the form of complexes for the encapsulation of active drugs or their covalent conjugates with inert carriers. In this respect nanotechnology offers an extensive spectrum of possible solutions. In this review, we discuss recent advances in the development of anthracycline prodrugs based on nanocarriers such as copolymers, lipids, DNA, and inorganic systems. The review focuses on the chemical architecture of the noncovalent nanocarrier–drug systems. | eng_Latn | 14,929 |
Synthesis and in vitro antibacterial evaluation of N-[5-(5-nitro-2-thienyl)-1,3,4-thiadiazole-2-yl] piperazinyl quinolones. | Abstract A series of N -[5-(5-nitro-2-thienyl)-1,3,4-thiadiazole-2-yl]piperazinyl quinolones ( 7a–c ) were synthesized and evaluated for in vitro antibacterial activity against some Gram-positive and Gram-negative bacteria. The antibacterial data revealed that compounds 7a – c had strong and better activity against tested Gram-positive organisms than the reference quinolones such as ciprofloxacin, norfloxacin and enoxacin. However, all three compounds were nearly inactive against Gram-negative bacteria. Compound 7a (ciprofloxacin analogue) was the most active compound against Gram-positive bacteria (MIC=0.008–0.015 μg mL −1 ). | TiCl((OPr)-Pr-i)(3) and NaBH(OAc)(3): an efficient reagent combination for the reductive amination of aldehydes by electron-deficient amines Sodium triacetoxyborohydride, NaBH(OAC)(3) with tri- isopropoxytitanium chloride, TiCl((OPr)-Pr-i)(3) is a useful reagent combination for reductive amination. Electron-deficient amines and heteroaromatic amines such as 2-aminopyrimidine and 2-aminothiazole can be reductively alkylated at room temperature to afford the corresponding secondary amines in good yields. © 2005 Elsevier Ltd. All rights reserved. | eng_Latn | 14,930 |
Improved Synthesis of 1-Boc-3,3-Dimethyl-piperazine | A simple and cost-saving process was developed for the preparation of 1-boc-3,3-dimethyl-piperazine starting from 2-amino-2-methyl-propionic acid and glycine. | Abstract C15H17NO4S, orthorhombic, Pbca (no. 61), a = 9.9890(11) Å, b = 14.4529(16) Å, c = 21.635(2) Å, V = 3123.4(6) Å3, Z = 8, Rgt(F) = 0.0565, wRref(F2) = 0.1656, T = 293(2) K. | eng_Latn | 14,931 |
Synthesis and Biological Evaluation of Some Novel pyrido[2,3-b]pyrazine derivatives as Potent TNF?alpha? inhibitors | Two series of 3-Methyl-pyrido[2,3-b]pyrazine-2-yl)substitutedphenylamines 3a-f and N-(3-methylpyrido[2,3-b]pyrazin-2-yl)substituted benzenesulfonamides 4a-f were synthesized and evaluated as novel TNF-α inhibitors. The latter compounds were tested for their ability to inhibit the production of TNF-α in vivo in rats. Compounds 4b, c and d exploited potent inhibitory activity with IC 50 = 0.025, 0.040 and 0.053 nM respectively. | OBJECT OF THIS PATENT are compounds of formula (I) or salts thereof, where R1, R (squared) are H, an aliphatic saturated or (SUBST.), Phenyl (n.), Or R1 YR (AL SQUARE) together with the nitrogen atom to which they are attached form a heterocyclic OF FORMULA 1 rING, being independently an integer of 1 to 3, R3 is H, an aliphatic saturated or (SUBST.) A REST phenyl, benzyl or phenethyl (n.), OR (squared) and R3 are together form a chain alkylene, R4 is hydrogen, an aliphatic saturated or alkoxy, and R5 is a pyrimidinyl (n.), triazinyl, triazolyl or A REST bicyclic nitrogenous heterocyclene. These compounds have valuable qualities HERBICIDES OR PLANT GROWTH REGULATORS. | eng_Latn | 14,932 |
Alkylation of 3-nitro-1,2,4-triazole in aqueous alkaline medium in the presence of N-methylmorpholine N-oxide and verification of the structure of the reaction products | It is shown that alkylation of 3-nitro-1,2,4-triazole with alkyl bromides may be carried out in an aqueous alkaline medium in the presence of N-methylmorpholine N-oxide. Alkylation of 3-nitro-1,2,4-triazole with dibromoethane and propargyl bromide occurs regioselectively with the formation of the substitution products at the N-1 atom of the heterocycle. Alkylation with allyl bromide under similar conditions proceeds with low selectivity leading to regioisomeric substitution products at both N-1 and N-2 atoms. Establishing the structures of the obtained regioisomers by NMR spectroscopy and X-ray crystallography is discussed. | Structural evolution of the quinqzoline as effective agents in the treatment of microbial infe ctions. Novel quinqzoline based thiosemicarbazide and styryl derivatives have been designed and synthesized. The structures of the synthesized compounds were assigned on the basis of elemental analysis, IR, 1H NMR. spectral data. All the newly synthesized compounds were screened against various strains of bacterial and fungi.it has been observed that compounds gave significant co-relation. | eng_Latn | 14,933 |
Quinoline-2-carbonitrile–fumaric acid (1/0.5) | The asymmetric unit of the title compound, C10H6N2·0.5C4H4O4, consists of one quinoline-2-carbonitrile molecule and a half-molecule of fumaric acid, which lies on an inversion center. The quinoline-2-carbonitrile molecule is almost planar, with an r.m.s. deviation of 0.008 (1) A. The acid and base are linked together via pairs of intermolecular C—H⋯O and O—H⋯N hydrogen bonds, forming R22(8) ring motifs. In the crystal, the carbonitrile molecules are further linked by intermolecular C—H⋯N hydrogen bonds, generating R22(10) ring motifs, resulting in zigzag chains running along the c axis. | Let C = IC(X) be the incidence coalgebra of an intervally finite partially ordered set X over a field. We investigate finiteness properties of C. We determine all C � -balanced bilinear forms on C, and we deduce that C is left (or right) quasi-co-Frobenius if and only if C is left (or right) co-Frobenius, and this is equivalent to the order relation on X being the equality. | oci_Latn | 14,934 |
5,12-Di(1-alkyl)thioquinanthrenediinium Bis-salts and 1-Alkyl-3-alkylthio-1,4-dihydro-4-thiooxoquinolines | The preparation of 5,12-di(1-alkyl)thioquinanthrenediinium bis-salts and their transformation into 1-alkyl-3-alkylthio-1,4-dihydro-4-thiooxoquinolines are described | Use: in medicine as an antiallergic agent. SUMMARY OF THE INVENTION: 2-derivatives of formula aminopirimi- dinonyl TTA VN NR 6 N-L 3 wherein L - AI Az - Az - A4 - bivalent radical of formula -CH CH-CH-CH-; -N CH-CH-CH-; -CH CH-CH-N -; n 0; 1 and 2: In the group NH, CH2, O or S. Reagent 1: Compound formulyR, i N Al. N Ch-1 VCHK V (CH, CN A Reagent 2: compound of formula:. Rs-vV5 N- / WK-W, & amp; deg; The reaction conditions are: a reaction-inert solvent, base Table 4.. | eng_Latn | 14,935 |
The Isolation of Isomeric 5-Oxazolones and the Assignment of Their Structures by Means of NMR Spectroscopy | In the syntheses of 5-oxazolones (2-isopropenyl-4-alkyl-2-oxazolin-5-ones) from N-meth-acryloyl-α-amino acids, new isomerized oxazolones were obtained. By NMR spectroscopy, the structures of isomerized oxazolones were determined to be pseudoxazolones (2-isopropylidene-4-alkyl-3-oxazolin-5-ones). The NMR spectra of several pseudoxazolones were measured and compared with the normal oxazolones. | Abstract A novel protecting group for the 2′-hydroxyl of ribonucleosides, p -nitrobenzyloxymethyl, is used in the rapid solid phase synthesis of the oligonucleotide U(U) 11 U; it can be readily removed from the oligomer product by treatment with tetrabutylammonium fluoride. | eng_Latn | 14,936 |
A construção de um mito: Antônio de Albuquerque e o levante emboaba | This article examines the construction of the image of peacemaker hero Antonio de Albuquerque, governor of the captaincy of Rio de Janeiro and then the captaincy of Sao Paulo and Minas do Ouro, considered responsible for the pacification of the War of Emboabas. Described by Claudio Manuel da Costa as a hero endowed with virtues like courage and wisdom, such image would then spread to historical studies, influencing the narratives on the War of Emboabas in particular, and the Albuquerque administration in general. | The reactivity of ruthenium(II)− and ruthenium(III)−chloride−dimethyl sulfoxide precursors and of the antimetasatic drug [ImH][trans-RuCl4(dmso-S)(Im)] (NAMI-A, Im = imidazole, dmso = dimethyl sulfoxide) toward NO was investigated. Treatment of [(dmso)2H][trans-RuCl4(dmso-S)2] and mer-RuCl3(dmso)3 with gaseous NO yielded [(dmso)2H][trans-RuCl4(dmso-O)(NO)] (1) and mer,cis-RuCl3(dmso-O)2(NO) (2), respectively. Thus, coordination of the strong π-acceptor NO induces a S to O linkage isomerization of the dmso trans to it to avoid competition for π-electrons. In light-protected nitromethane solutions, complex 2 equilibrates slowly with the two isomers mer-RuCl3(dmso-S)(dmso-O)(NO) (3), with NO trans to Cl, and mer-RuCl3(dmso-S)(dmso-O)(NO) (4), with NO trans to dmso-O; the equilibrium mixture consists of ca. 64% 2, 3% 3, and 33% 4. Treatment of the Ru(II) precursor trans-RuCl2(dmso-S)4 with gaseous NO in CH2Cl2 solution yielded the nitrosyl−nitro derivative trans,cis,cis-RuCl2(dmso-O)2(NO)(NO2) (5). Finally, [... | por_Latn | 14,937 |
Synthesis and antibacterial activity of 1-N-(β-d-glucopyranosyl)-4-((1-substituted-1H-1,2,3-triazol-4-yl)ethoxymethyl)-1,2,3-triazoles | Abstract Four gluco-triazole conjugates were synthesized employing Cu(I) catalyzed click reactions between peracetylated glucosyl azide and alkyl-(propynoxy)ethyl-triazoles which in turn were prepared under similar reaction conditions using the appropriate alkyl azide (C7, C8, C10, and C12) and but-3-yn-1-ol. Removal of the acetyl protecting groups afforded additional four compounds. All eight conjugates were assessed toward inhibition of bacterial growth ( Escherichia coli , Staphylococcus aureus ). Slight growth inhibition compared to kanamycin was observed at a concentration of 20 μg/mL, while no growth inhibition was observed at the lowest concentration (5 μg/mL). | TiCl((OPr)-Pr-i)(3) and NaBH(OAc)(3): an efficient reagent combination for the reductive amination of aldehydes by electron-deficient amines Sodium triacetoxyborohydride, NaBH(OAC)(3) with tri- isopropoxytitanium chloride, TiCl((OPr)-Pr-i)(3) is a useful reagent combination for reductive amination. Electron-deficient amines and heteroaromatic amines such as 2-aminopyrimidine and 2-aminothiazole can be reductively alkylated at room temperature to afford the corresponding secondary amines in good yields. © 2005 Elsevier Ltd. All rights reserved. | eng_Latn | 14,938 |
WEAKLY BONDED LEWIS BASE ADDUCTS OF PLUMBOCENE AND STANNOCENE : A SYNTHETIC AND CALCULATIONAL STUDY | The coordination of [(η-Cp)2Pb] and [(η-Cp)2Sn] by bidentate Lewis-base ligands gives the first examples of adducts of neutral p-block metallocenes. Ab initio MO calculations of [(η-Cp)2Pb·TMEDA] (1) (TMEDA = (Me2NCH2)2), [Cp2Pb·4,4‘-Me2bipy] (2) (4,4‘-Me2bipy = 4,4‘-dimethylbipyridine), and the new complex [(η-Cp)2Sn·TMEDA] (3) confirm that despite the presence of longer Pb−N and Sn−N bonds in the solid-state structures of the TMEDA adducts, the association of TMEDA with the metallocenes is more favorable than with 4,4‘-Me2bipy. This finding is a consequence of the greater reorganization energy of 4,4‘-Me2bipy compared to TMEDA. The low association energies of these species can be rationalized in terms of metal lone pair/ligand lone pair repulsion. | A representative of a new class of sesquiterpenes, for which the title dunnianes is proposed, has been isolated from the medicinal plant Illicium dunnianum. The structure of this novel compound was determined by 2D-NMR spectroscopy. The biosynthesis of the dunniane class of sesquiterpenes, which may be related to that of the cuparanes, is discussed. | yue_Hant | 14,939 |
Pyrazolotrithiadiazepines and their unexpected rearrangement to 1,2,3-dithiazoles | Treatment of 6-bromotrithiadiazepine (1) with Hunig's base in the presence of diaryldiazomethanes (2) gives the trithiadiazepyne cycloadducts (3) which undergo a deep-seated thermal rearrangement to give fused 1,2,3-dithiazoles (4), for which a mechanism is proposed. | [Formula 1] The present invention provides a group of piperazine derivatives mesylate, and a method for the preparation of these mesylates in high yield and high purity economical way. According to the method of the present invention, synthesis of the piperazine ring and the mesylate product are combined in a single reaction step. The present invention, X is a bicyclic heterocyclic phenyl group and Y is methyl, (optionally substituted by fluorine in some cases) ethyl, cycloalkyl (3-7C) methyl, benzyl or m- phenyl benzyl in which, on the mesylate of the compound of formula (1). | eng_Latn | 14,940 |
What Can Make Joint Diagonalization Difficult? | We show that the issues of uniqueness and noise sensitivity in the problem of matrix joint diagonalization are closely related. We address other factors important in noise sensitivity. We distinguish between orthogonal and non-orthogonal joint diagonalization and argue that the latter can be more difficult than the former. Our analysis is based on the perturbation analysis of the stationary points of certain flows for joint diagonalization. Numerical experiments support the derived results. | During the last eight years a number of aspects of ::: amide chemistry have been studied in the Chemistry ::: Department, University of Tasmania, under the direction ::: of Dr. J. B. Polya. Acylation of amides to diacylamines ::: was investigated, and satisfactory syntheses were developed ::: for unsymmetrical diacylamines (R1 ::: .CO.NH.CO.R2; R1≠R2 ). In some cases such diacylamines, through reacylation, ::: may form mixtures of the two corresponding ::: symmetrical diacylamines. Diacylamines react with hydrazines ::: to form 1:2:4-triazoles, which are convenient ::: derivatives indicating the structure of the diacylamine. ::: With a hydrazine R.NH.NH2 an unsymmetrical diacylamine ::: of the type indicated could form 1R-3R1 -5R2 - and ::: 1R-3R2 -5R1 -1:2:4-triazole. Proving the orientations of ::: the products from a number of diacylamines seemed a ::: promising way to investigate the mechanism of this triazole ::: synthesis. | eng_Latn | 14,941 |
Formation and aromatization of strained bicyclic pyrazolidines via tandem reaction of alkyl 2-aroyl-1-chlorocyclopropanecarboxylates with acylhydrazones | A base-promoted reaction between alkyl 2-aroyl-1-chlorocyclopropanecarboxylates and acylhydrazones is described. In common solvents, the reactions proceed smoothly under mild conditions, providing mainly the formal substitution product , as well as a little amount of the formal [3 + 2] cycloaddition product . This strained bicyclic pyrazolidine , however, became the predominant product in DMSO. Moreover, a novel aromatization process of the fused pyrazolidine into 2,3,5-trisubstituted pyrrole has been successfully achieved in excellent yield via treatment with a HCl-pyridine system. | Tautomeric structures of 3-amino[1,2,4]triazolo[4,3- a ]pyrimidin-5-one in the gas phase and aqueous solution were investigated using DFT B3LYP/6-311++(2d,2p) calculations. Intramolecular hydrogen bond parameters were calculated and their influence on the stability of the tautomeric forms evaluated using the quantum theory of "atoms in molecules". How to Cite Astakhov, A. V.; Chernyshev, V. M. Chem. Heterocycl. Compd. 2014 , 50 , 319. [ Khim. Geterotsikl. Soedin. 2014 , 349.] For this article in the English edition see DOI 10.1007/s10593-014-1479-2 | eng_Latn | 14,942 |
Efficient Synthetic Method of 1,2-substituted benzimidazoles | The benzimidazole exhibits widespread activities,and the benzimidazole nucleus is found in a variety of drugs.In this paper,we research a new and efficient synthetic method of 1,2-disubstituted benzimidazole.o-phenylenediamine and ketone form schiff bases having one free amine group with microwave,and then schiff bases condensed with different aldehydes to give five 1,2-substituted benzimidazoles.The mechanism of reaction involves 1,3 shift of negative hydrogen ion. | Meso-meso coupled diporphyrins were prepared from 5,10,15-trisubstituted zinc-porphyrins in high yields upon treatment with AgPF6 alone or with AgPF6 and I2. | eng_Latn | 14,943 |
The use of acyl derivatives of N-hydroxy-2-thiopyridone in a simple synthesis of pyrrolidines and tetrahydrofurans | Photolysis of the N-hydroxy-2-thiopyridone derivatives of 3-N-acetylallylamino, 3-N,N-diallylamino and 3-allyloxy-propionic acids gave cleanly derivatives of N-acetyl-3-methylpyrrolidine, N-allyl-3-methylpirrolidine and of 3-methyltetrahydrofuran respectively. The corresponding reaction with 3-allylthiopropionic acid afforded a radical which fragmented to ethylene and the allylthio radical without cyclization. | Treatment of 6-bromotrithiadiazepine (1) with Hunig's base in the presence of diaryldiazomethanes (2) gives the trithiadiazepyne cycloadducts (3) which undergo a deep-seated thermal rearrangement to give fused 1,2,3-dithiazoles (4), for which a mechanism is proposed. | eng_Latn | 14,944 |
Effect of geometric parameters of substituted malonate anions on coordination environment of CuII atoms coordinated with 2,2′;6′,2″-terpyridine | Structural data for known and newly obtained copper(II) complexes with 2,2′;6′,2″-terpyridine and substituted malonic (dimethylmalonic, 1,1-cyclopropane- and 1,1-cyclobutanedicarboxylic) acid dianions R2mal2- were used to show that the coordination environment of the metallocenter depends on the (O2C)C—C—C(CO2) angle. A chelate coordination of the R2mal2- dianion is realized for 1,1-cyclopropanedicarboxylate anion (~122.9°), while the dimethylmalonate and 1,1-cyclobutanedicarboxylate anions (107.4–110.8°) are characterized by a monodentate coordination. | A detailed analysis of the structure of the quark version of the parton model incorporating algebraic (SU2 orSU3) configurations and their mixing is given in which the only assumptions retained are those of the quark-parton identity. The model is shown to be wholly consistent but less predictive than applications of it would suggest. | eng_Latn | 14,945 |
Long-term effects of an amiloride/hydrochlorothiazide combination ('Moduretic') on electrolyte balance. | SummaryA study was carried out of plasma electrolyte estimations made before and after long-term use of a combination of amiloride and hydrochlorothiazide in 23 patients. The mean duration of use was 20.3 months. No significant differences were found in plasma potassium, sodium, bicarbonate or urea from baseline levels. | During the last eight years a number of aspects of ::: amide chemistry have been studied in the Chemistry ::: Department, University of Tasmania, under the direction ::: of Dr. J. B. Polya. Acylation of amides to diacylamines ::: was investigated, and satisfactory syntheses were developed ::: for unsymmetrical diacylamines (R1 ::: .CO.NH.CO.R2; R1≠R2 ). In some cases such diacylamines, through reacylation, ::: may form mixtures of the two corresponding ::: symmetrical diacylamines. Diacylamines react with hydrazines ::: to form 1:2:4-triazoles, which are convenient ::: derivatives indicating the structure of the diacylamine. ::: With a hydrazine R.NH.NH2 an unsymmetrical diacylamine ::: of the type indicated could form 1R-3R1 -5R2 - and ::: 1R-3R2 -5R1 -1:2:4-triazole. Proving the orientations of ::: the products from a number of diacylamines seemed a ::: promising way to investigate the mechanism of this triazole ::: synthesis. | eng_Latn | 14,946 |
Allergic responses and aryl hydrocarbon receptor novel pathway of mast cell activation. | The activation of the transcription factor aryl hydrocarbon receptor (AhR) is modulated by a wide variety of xenobiotics and ligands deriving from products of metabolism. The study of the contribution of AhR to allergic diseases has gained much interest in recent years. Here we discuss the role that environmental factors and metabolic products, particularly acting on AhR-expressing mast cells (MCs), could have in the development of local allergic/atopic response. Thus, this review will cover: a brief overview of the AhR mechanism of action in the immune system; a description of different AhR ligands and their effects to IgE-mediated MC activation in the allergic response, with particular attention to the role of IL-17; a discussion about the potential involvement of AhR in immune tolerance; and a conclusion on human diseases in which direct AhR activation of MC might have a major impact. | During the last eight years a number of aspects of ::: amide chemistry have been studied in the Chemistry ::: Department, University of Tasmania, under the direction ::: of Dr. J. B. Polya. Acylation of amides to diacylamines ::: was investigated, and satisfactory syntheses were developed ::: for unsymmetrical diacylamines (R1 ::: .CO.NH.CO.R2; R1≠R2 ). In some cases such diacylamines, through reacylation, ::: may form mixtures of the two corresponding ::: symmetrical diacylamines. Diacylamines react with hydrazines ::: to form 1:2:4-triazoles, which are convenient ::: derivatives indicating the structure of the diacylamine. ::: With a hydrazine R.NH.NH2 an unsymmetrical diacylamine ::: of the type indicated could form 1R-3R1 -5R2 - and ::: 1R-3R2 -5R1 -1:2:4-triazole. Proving the orientations of ::: the products from a number of diacylamines seemed a ::: promising way to investigate the mechanism of this triazole ::: synthesis. | eng_Latn | 14,947 |
Formation of Nickel(II) Coordination Polymers by a Double Betaine: [{Ni(L)(H2O) 2} n] Cl2n.2nH2O and [{Ni(L)2(H2O)2} n | Two novel polymeric nickel(II) complexes of a double betaine with a rigidtris(ethylene) bridge between the pair of nitrogen atoms, namely [ {Ni(L)(H2O)4 }n]Cl2n.2nH2O(1)and [ {Ni(L)2(H2O)2} n](ClO4)2n.4nH2O(2) [L =¯O2CCH2N+(CH2CH2)3N+CH2CO2¯], have been prepared and characterized by X-ray crystallography. Thenickel(II) atom in either complex is coordinated by unidentate carboxylategroups and aqua ligands in a distorted octahedral geometry. The crystalstructure of (1) features an infinite zigzag chain composed of an alternatearrangement of metal atoms and double betaine ligands, and hydrogen bondingamong adjacent chains leads to a three-dimensional network. Complex (2)exhibits a wave-like layer structure corresponding to the (2 0 0) family ofplanes. | AbstractFrom extraction experiments in the two-phase water-nitrobenzene system and γ-activity measurements, the stability constants of the tetraethyl p-tert-butyltetrathiacalix[4]arene tetraacetate (cone)·M + complexes (M + = Li + , H 3 O + , NH 4 + , Ag + , or K + ) were determined in water-saturated nitrobenzene. It was found that these constants increase in the cation order NH 4 + < K + < H 3 O + < Ag + < Li + < Na + .Graphical Abstract[IMAGE] | eng_Latn | 14,948 |
Studies on the chemistry of triazoles | During the last eight years a number of aspects of ::: amide chemistry have been studied in the Chemistry ::: Department, University of Tasmania, under the direction ::: of Dr. J. B. Polya. Acylation of amides to diacylamines ::: was investigated, and satisfactory syntheses were developed ::: for unsymmetrical diacylamines (R1 ::: .CO.NH.CO.R2; R1≠R2 ). In some cases such diacylamines, through reacylation, ::: may form mixtures of the two corresponding ::: symmetrical diacylamines. Diacylamines react with hydrazines ::: to form 1:2:4-triazoles, which are convenient ::: derivatives indicating the structure of the diacylamine. ::: With a hydrazine R.NH.NH2 an unsymmetrical diacylamine ::: of the type indicated could form 1R-3R1 -5R2 - and ::: 1R-3R2 -5R1 -1:2:4-triazole. Proving the orientations of ::: the products from a number of diacylamines seemed a ::: promising way to investigate the mechanism of this triazole ::: synthesis. | The present invention relates to pyrimidine nucleosides containing antibiotics and hymexazol fungicidal composition, wherein the active ingredient is a pyrimidine nucleoside antibiotics and hymexazol, pyrimidine nucleoside antibiotics and hymexazol a weight ratio of 32: 3 -1: 48. The fungicidal compositions of the present invention, good control efficiency, low cost, can delay development of resistance bacteria. | eng_Latn | 14,949 |
Chemoenzymatic syntheses of (R)-2-bromo-, (R)2-chloro- and (R)2-azido-1-(1,3-benzodioxol-5-yl)-1-ethanol | Abstract Enantioselective reductions of 2-X-1-(1,3-benzodioxol-5-yl)-1-ethanones, (X = Cl, Br, N 3 ) by Rhodothorula glutinis CCT 2182 afforded the corresponding ( R )-ethanols in good to excellent yields (57–99%) and excellent enantiomeric excesses (>99%). These alcohols may be used as raw materials for the preparation of the pharmaceuticals ( R )-(−)-epinephrine, ( R )-(−)-norepinephrine and ( R )-(−)-isoproterenol. | Pyrazino[2,3-c]azepine and azepino[3,4-b]quinoxaline represent new ring systems and were prepared by fusing either of pyrazine ring onto azepine derivative or vice versa. Intramolecular 1,7-carbonyl-enamine cyclization was studied as a new mode for azepine ring closure. Various examples and reaction conditions were studied for this ring closure. | eng_Latn | 14,950 |
Crystal structure of 2-aminophenylammonium— 6-oxo-1,6-dihydropyridazine- 3-carboxylate (1:1), C11H12N4O3 | Abstract C11H12N4O3, monoclinic, P21/c (no. 14), a = 12.0039(6) Å, b = 9.5916(4) Å, c = 10.5824(5) Å, β = 109.429(3)°, V = 1149.1 Å3, Z = 4, Rgt(F) = 0.0456, wRref(F2) = 0.1032, T = 120 K. | Several trimethylcyclopentyl and trimethylcyclopentenyl acetanilides, mono- and di-substituted on the aromatic nucleus as well as the corresponding acyl derivatives from aniline it self and corresponding phenylacetanilides, were prepared and tested as analgesics and antipyretics. Several compounds exhibit considerable activity in some cases superior to that of acetanilide. | eng_Latn | 14,951 |
Noncentrosymmetric mixed-cation borate: Crystal growth, structure and optical properties of Cs2Ca[B4O5(OH)4]2·8H2O | Abstract A single crystal of the new noncentrosymmetric material Cs 2 Ca[B 4 O 5 (OH) 4 ] 2 ·8H 2 O has been grown by a slow evaporation method with sizes up to 10×10×5 mm 3 using an aqueous acetone solution as a solvent. The crystal structure of this compound was determined by single crystal X-ray diffraction. It crystallizes in the Orthorhombic space group P2 1 2 1 2 1 with lattice parameters a =11.5158(7) A, b =12.8558(7) A, c =16.7976(10) A and Z =4. The optical transmittance spectrum was measured on the Cs 2 Ca[B 4 O 5 (OH) 4 ] 2 ·8H 2 O crystal, which exhibits an absorption edge at about 190 nm in the UV region. The powder second-harmonic generation (SHG) measurement indicates that Cs 2 Ca[B 4 O 5 (OH) 4 ] 2 ·8H 2 O is phase-matchable and the signal is about half that of a KDP (KH 2 PO 4 ) standard. Theoretical calculation shows it has moderate birefringence, and identifies the contribution of cations to the optical properties. | TiCl((OPr)-Pr-i)(3) and NaBH(OAc)(3): an efficient reagent combination for the reductive amination of aldehydes by electron-deficient amines Sodium triacetoxyborohydride, NaBH(OAC)(3) with tri- isopropoxytitanium chloride, TiCl((OPr)-Pr-i)(3) is a useful reagent combination for reductive amination. Electron-deficient amines and heteroaromatic amines such as 2-aminopyrimidine and 2-aminothiazole can be reductively alkylated at room temperature to afford the corresponding secondary amines in good yields. © 2005 Elsevier Ltd. All rights reserved. | eng_Latn | 14,952 |
Base catalysed synthesis of thiochromans and azo-linked chromenes using allenylphosphonates | An efficient base catalysed approach to the synthesis of thiochromans/chromenes from allenylphosphonates (and an allenoate) and substrates having SH/OH and CHO groups at appropriate positions has been developed. Several azo-linked chromenes that are bright red pigments are also synthesized. This methodology involves the domino reactions of Michael addition and subsequent cyclisation by intramolecular aldol reaction. | Abstract The 119Sn Mossbauer parameters for some chalcogen-containing Zintl phases of composition M4SnX4 (M=Na, K; X=S, Se, Te), Na2SnSe3, M3SnTe3 (M=K, Rb, Cs), Cs4Sn2Te7 and M2SnTe5 (M=K, Rb) are reported. All the compounds contain tetrahedrally coordinated tin and the chemical isomer shift data show the tin to be involved in covalent bonding with the chalcogen atoms. The dependence of the 119Sn Mossbauer parameters on the local coordination of tin, the extent of polymerisation of the anionic sub units, the transfer of electrons from the alkali metal to the anionic units, and the electronegativity of the chalcogen atoms are discussed. | eng_Latn | 14,953 |
Nonlinear Opt ical Propert ies of Conjugated Molecules | Due to their intrinsic orientational anisotropy and elevated polarizability n-conjugated polymers are widely perceived as promising materials for use in nonlinear optical devices. Advances in the development of practical systems have been impeded, however, by the difficulties in developing a realistic theoretical description of the experimental situation. In this paper we present several examples of theoretical progress towards this goal and discuss how the different effects contributing to the polarization response in the systems can be quanti fied. | (57) Abstract: The present invention, as substance P antagonists, compounds of formula (I), these N- oxide forms, For these pharmaceutically may receive addition salts and their stereochemically isomeric forms in the above formula, n is 0, 1 or 2, m is 1 or 2, when m is 2, n is 1, p is 0, 1 or 2, = Q is = O or = NR Le is Het or HetC Kiruokishi, a C | eng_Latn | 14,954 |
Dinuclear Copper(I) Complexes of Phenanthrolinyl-Functionalized NHC Ligands | We have prepared a number of phenanthroline-functionalized imidazolium and triazolium salts from 2-iodo-1,10-phenanthroline and imidazole and triazole derivatives. Simple reactions of these imidazolium salts with copper powder at room temperature have afforded a series of dinuclear copper(I)-NHC complexes doubly bridged by N-(1,10-phenanthrolin-2-yl)imidazolylidene ligands in excellent yields. The two phen-NHC ligands are either head-to-head or head-to-tail arranged depending upon the steric repulsion of the substituents. Reactions of imidazolium halides and copper yielded dinuclear complexes [Cu2(μ-X)(L6)2]X (X = Cl, Br, I) in nearly quantitative yields. The dinuclear [Cu2(L10)2(μ-MeCN)]2+ was similarly obtained through 1,2,4-triazolium salts and copper, and the compound consists of a bridging CH3CN molecule, representing the first example of Cu-NHC complexes with a 3c–2e bond. These Cu(I) complexes have been characterized by NMR spectra and elemental analysis and further confirmed by X-ray diffraction a... | Abstract A multistep direct reaction model with pickup is extended to described the formation of tritons and 3 He-particles in nucleon- and pion-induced precompound reactions. In the latter ones, those tritons not accounted for by pickup can be explained as primary ones from absorption by α-clusters, for which a 10% probability is deduced. | eng_Latn | 14,955 |
Synthesis and Biological Activity of N-Sulfonyltripeptides with C-Terminal Arginine as Potential Serine Proteases Inhibitors | Tripeptides of the general X-SO2-d-Ser-AA-Arg-CO-Y formula, where X = α-tolyl, p-tolyl, 2,4,6-triisopropylphenyl; AA = alanine, glycine, norvaline and Y = OH, NH-(CH2)5NH2 were obtained and tested for their effect on the amidolytic activities of urokinase, thrombin, trypsin, plasmin, t-PA and kallikrein. The most active compound towards urokinase was PhCH2SO2-d-Ser-Gly-Arg-OH with Ki value 5.4 μM and the most active compound toward thrombin was PhCH2SO2-d-Ser-NVa-Arg-OH with Ki value 0.82 μM. The peptides were nontoxic against porcine erythrocytes in vitro. PhCH2SO2-d-Ser-Gly-Arg-OH showed cytotoxic effect against DLD cell lines with IC50 values of 5 μM. For the highly selective determination of the interaction of some of the synthesised acids of tripeptides with urokinase and plasmin the Surface Plasmon Resonance Imaging sensor has been applied. These compounds bind to urokinase and plasmin in 0.05 mM concentration. | TiCl((OPr)-Pr-i)(3) and NaBH(OAc)(3): an efficient reagent combination for the reductive amination of aldehydes by electron-deficient amines Sodium triacetoxyborohydride, NaBH(OAC)(3) with tri- isopropoxytitanium chloride, TiCl((OPr)-Pr-i)(3) is a useful reagent combination for reductive amination. Electron-deficient amines and heteroaromatic amines such as 2-aminopyrimidine and 2-aminothiazole can be reductively alkylated at room temperature to afford the corresponding secondary amines in good yields. © 2005 Elsevier Ltd. All rights reserved. | eng_Latn | 14,956 |
A new ligand for copper-catalyzed amination of aryl halides to primary(hetero)aryl amines | Abstract N,N'-bis(3,5-dimethoxyphenyl)cyclopentane-1,1-dicarboxamide was found as a new ligand for copper-catalyzed amination of aryl iodides, bromides and chlorides to afford various primary (hetero)aryl amines. These reactions proceeded efficiently under mild conditions when inexpensive aqueous ammonia (28% NH3 in H2O) was used as the amino source. | Abstract We report, for the first time, the observation of natural, polytypoidic superlattice structures in pulsed laser deposited superconducting Y-Ba-Cu-O thin films. These structures correspond to ordered stacking sequences of the “123”, “124” and “224” cationic ratios. Such structurally coherent, natural superlattice structures, either in the stable or metastable form, may be an attractive alternative for the artificial superlattices suggested for novel electronic applications. The results suggest the existence of a family of polytypoidic phases with different cationic compositions in the Y-Ba-Cu-O phase diagram. | eng_Latn | 14,957 |
Conversion of aromatic aldehydes into 1-aryl-2,2-dichloroethenes | A new general one-pot preparative method for the synthesis of 1-aryl(hetaryl)-2,2-dichloroethenes from aldehydes was developed. The method involves successive conversions of the latter into hydrazones followed by treatment with carbon tetrachloride in the presence of copper(i) chloride. | Abstract The first ruthenium catalyzed redox-neutral C–H activation strategy for the ring-opening of diazabicyclic olefins via C–H bond cleavage of phenyl azoles is reported. The developed method offers a novel route to functionalized cyclopentenes by employing less-expensive ruthenium catalyst and readily accessible biologically significant heteroarenes. The present protocol is a merger of the C–H activation of phenyl substituted heteroaromatics and subsequent β-nitrogen elimination of diazabicyclic olefins. | eng_Latn | 14,958 |
The X-Ray Crystal Structure of Trimethyltin (IV) Azide. A Unique One-Dimensional (ch3)3Sn) Delta + (ch3)3Sn(N3)2) Delta-)n Polymer. | Abstract : Our 1978 review of the tin structural literature reveals many examples of axially-most electronegative, trigonal bipyramidal triorganotin moieties in associated polymer chains, but the structure of trimethyltin azide is unique in consisting of SnC3 moieties in alternating (CH3) 3 Sn(delta +) cationic and N3(CH3)3SnN3 (delta -) aniotic environments in a one-dimensional array with the tin atoms bridged at unequal distances by the alpha-nitrogen atoms of the azide group at which site the chains are bent. (Author) | 1. ::: ::: The formation of trace amounts of a chloro-substituted nonbenzoid aromatic derivative, namely, 4-methyl-5-chloro-2,4,6-cycloheptatrien-1-one under standard Zincke-Suhl reaction conditions, was detected. ::: ::: ::: ::: ::: 2. ::: ::: The possibility was demonstrated for the formation of the product of the “anomalous Reimer-Tiemann reaction” (Auwers reaction), namely, 4-methyl-4-dichloromethyl-2,5-cyclohexadien-1-one in a Zincke-Suhl-type reaction using CHCl3 instead of the usual reagent, CCl4. | eng_Latn | 14,959 |
Carbonyl-Enamine a New Mode for Azepine Ring Closure : Synthesis and Characterization of Pyrazino[2,3-c]azepine, as a New Ring System | Pyrazino[2,3-c]azepine and azepino[3,4-b]quinoxaline represent new ring systems and were prepared by fusing either of pyrazine ring onto azepine derivative or vice versa. Intramolecular 1,7-carbonyl-enamine cyclization was studied as a new mode for azepine ring closure. Various examples and reaction conditions were studied for this ring closure. | The behavior of amines as catalysts for oxirane acidolysis and phenolysis has been studied using kinetic methods. The apparent catalytic and noncatalytic reaction rate constants have been estimated. It has been demonstrated that the noncatalytic pathway has almost no effect on the apparent reaction rate constant. In order to determine the character of the behavior of amines (bases/nucleophiles) in this reaction, their reactivity has been analyzed within the conceptions of basic and nucleophilic mechanisms of catalysis. Based on the quantitative amine structure—catalytic activity correlation, it has been shown by comparing the values of correlation coefficients (r) of equations describing mechanisms for various reaction systems that, in the reactions of oxiranes with proton donors (carboxylic acids and phenols), the catalytic activity of tertiary amines/pyridines is determined by their nucleophilicity rather than basicity. | eng_Latn | 14,960 |
Synthesis and reactivity of a putative biogenetic precursor to tricholomenyns B, C, D and E | A chemoenzymatic synthesis of the putative biogenetic precursor, 6, to the epoxy-quinol type natural products, tricholomenyns B, C, D and E (2–5, respectively), has been achieved. However, treatment of compound 6 under a variety of conditions failed to effect its conversion into any of the natural products 2–5. In contrast, the simple model system 22 reacts with acetic acid in the presence of stoichiometric quantities of Ti(OPr-i)4 to give the diacetate 23. | Abstract Enantioselective reductions of 2-X-1-(1,3-benzodioxol-5-yl)-1-ethanones, (X = Cl, Br, N 3 ) by Rhodothorula glutinis CCT 2182 afforded the corresponding ( R )-ethanols in good to excellent yields (57–99%) and excellent enantiomeric excesses (>99%). These alcohols may be used as raw materials for the preparation of the pharmaceuticals ( R )-(−)-epinephrine, ( R )-(−)-norepinephrine and ( R )-(−)-isoproterenol. | eng_Latn | 14,961 |
ChemInform Abstract: Cu(I)/TF-BiphamPhos-Catalyzed Asymmetric Michael Addition of Cyclic Ketimino Esters to Alkylidene Malonates. | An efficient method for the construction of β-branched α-amino acids containing adjacent quaternary and tertiary stereogenic centers with excellent diastereo- and enantioselectivities is developed. | The reduction reaction of bis(salicylidieneamino)methyl-2-phenol with potassium borohydride was studied.The product was bis(2-hydroxybenzyl)amine,not the expected bridging triphenol,due to the cleavage of a C-N bond.Sodium bis 2-oxidobenzyl ammonium was obtained by dissolving the bis(2-hydroxybenzyl)amine in a NaOH solution,and its molecular structure was elucidated by single crystal X-ray diffraction analysis. | eng_Latn | 14,962 |
Cyclic Hexapeptide Dimers, Antatollamides A and B, from the Ascidian, Didemnum molle. A Tryptophan-Derived Auxiliary for L- and D-Amino Acid Assignments | Two dimerized cyclic hexapeptides, antatollamides A (1) and B (2), were isolated from the colonial ascidian Didemnum molle collected in Pohnpei. The amino acid compositions and sequences were determined by interpretation of MS and 1D and 2D NMR data. Raney Ni reduction of antatollamide A cleaved the dimer to the corresponding monomeric cyclic hexapeptide with replacement of Cys by Ala. The amino acid configuration of 1 was established, after total hydrolysis, by derivatization with a new chiral reagent, (5-fluoro-2,4-dinitrophenyl)-Nα-l-tryptophanamide (FDTA), prepared from l-Trp, followed by LCMS analysis; all amino acids were found to be l-configured except for d-Ala. | Use: in medicine as an antiallergic agent. SUMMARY OF THE INVENTION: 2-derivatives of formula aminopirimi- dinonyl TTA VN NR 6 N-L 3 wherein L - AI Az - Az - A4 - bivalent radical of formula -CH CH-CH-CH-; -N CH-CH-CH-; -CH CH-CH-N -; n 0; 1 and 2: In the group NH, CH2, O or S. Reagent 1: Compound formulyR, i N Al. N Ch-1 VCHK V (CH, CN A Reagent 2: compound of formula:. Rs-vV5 N- / WK-W, & amp; deg; The reaction conditions are: a reaction-inert solvent, base Table 4.. | eng_Latn | 14,963 |
Zur Synthese von 4-Aryl-5,6-dihydro-benzo[h]chinolinen | A new route to the benzo[h]quinoline system3 byMichael-addition of malononitrile to 2-arylidene-1-tetralones1 is presented. The mechanism of this reaction is elucidated by isolation of the intermediate 4H-naphtho[1,2—b]-pyrane2 and its reaction to3. The reaction is proposed to be a sequence of addition, cyclisation,Dimroth-rearrangement and disproportionation. | During the last eight years a number of aspects of ::: amide chemistry have been studied in the Chemistry ::: Department, University of Tasmania, under the direction ::: of Dr. J. B. Polya. Acylation of amides to diacylamines ::: was investigated, and satisfactory syntheses were developed ::: for unsymmetrical diacylamines (R1 ::: .CO.NH.CO.R2; R1≠R2 ). In some cases such diacylamines, through reacylation, ::: may form mixtures of the two corresponding ::: symmetrical diacylamines. Diacylamines react with hydrazines ::: to form 1:2:4-triazoles, which are convenient ::: derivatives indicating the structure of the diacylamine. ::: With a hydrazine R.NH.NH2 an unsymmetrical diacylamine ::: of the type indicated could form 1R-3R1 -5R2 - and ::: 1R-3R2 -5R1 -1:2:4-triazole. Proving the orientations of ::: the products from a number of diacylamines seemed a ::: promising way to investigate the mechanism of this triazole ::: synthesis. | deu_Latn | 14,964 |
Reaction of N-acylsulfilimines with diphenyl ketene. A new synthesis of 2-oxazolin-4-ones | Abstract 2-Substituted-5,5-diphenyl-2-oxazolin-4-ones 1 are prepared in good to high yields by reaction of diphenyl ketene and N-acylsulfilimes. | In the title compound, C(26)H(24)N(2)O(3)Se, the selenadiazole ring is planar [maximum deviation = 0.002 (2) Å]. The dihedral angle between the selenadiazole ring and the attached phenyl ring is 49.00 (13)°. The crystal structure is stabilized by inter-molecular C-H⋯N and C-H⋯π inter-actions. | eng_Latn | 14,965 |
Oxazole, pyrazole and piperidine derivatives having an o-hydroxyaryl moiety with anticipated molluscicidal activity | The condensation reactions of hippuric acid and its furyl derivative with salicylaldehydes or that of salicylhippuric acid analogues with furaldehyde led to the corresponding oxazoles. These were subsequently treated with hydrazine hydrate, hydroxylamine or subjected to alkaline hydrolysis to yield new o-hydroxyaryl or salicyl containing derivatives. 5-Substituted salicylanilides were treated with piperidine and formaldehyde in a Mannich type reaction affording the corresponding 3-(N-piperidinomethyl) salicylanilides. It was noticed that the presence of an electron donating group in position 3 in the salicylanilide moiety decreases the molluscicidal activity. | Multiple orthogonal coordinative interactions were utilized to construct heterometal-decorated tetrahedral cages from in situ formed trinuclear ZrIV clusters through the combination with other metal ions such as CuII or PdII . Through effective use of the hard/soft acid/base principle, the orthogonal self-assembly process of Zr-bpydc-CuCl2 (H2 bpydc=2,2-bipyridine-5,5-dicarboxylic acid) can be finely controlled using three strategies: post-synthetic metallization, a stepwise metalloligand approach, or a one-pot reaction. | eng_Latn | 14,966 |
N-Benzyl-2-(2,4-dichlorophenoxy)acetamide | In the title compound, C15H13Cl2NO2, the dihedral angle between the aromatic rings is 27.17 (11)°. In the crystal the molecules are linked by N—H⋯O hydrogen bonds. | Five new complexes, [(NH3)5Co(dicarboxylate)Co(NH3)5]X4 (dicarboxylate=oxalate, succinate, pimelate, fumarate, and maleate; X=ClO4− or Cl−), were synthesized by the reactions of [Co(hydrogen dicarboxylate)(NH3)5](ClO4)2 with [Co(NH3)5(H2O)](ClO4)3 and characterized by chromatographic behavior and electronic and NMR techniques. When maleate was used as the dicarboxylate, the formation of [(NH3)5Co(fumarate)Co(NH3)5]4+ as well as [(NH3)5Co(maleate)Co(NH3)5]4+ was observed. The IR and Raman spectra of [(NH3)5Co(oxalate)Co(NH3)5]4+ indicate that the symmetry of the oxalate ion in the complex may be approximated by D2h. | eng_Latn | 14,967 |
1-aryl- and 1-benzyl-3,5-diethoxycarbonyl-1,4-dihydropyridines | The possibility has been studied of using anilines in the Hantzsch synthesis. It has been shown that, with the exception of those containing strong electron-accepting substituents, they take part in this reaction with the formation of 1-aryl-1,4-dihydropyridines. The reaction largely depends on the nature of the substituents in the aniline and in the benzaldehyde and is promoted by electron-accepting substituents in the aldehyde and electron-donating substituents in the amine. The mechanism of the reaction is discussed. A number of 1-benzyl-1,4-dihydropyridines have been synthesized. The UV, IR, and PMR spectra and the electro-oxidation of the compounds obtained have been studied. | Abstract Azidodiols, bromodiols and triol derivatives were regioselectively monooxidised to the corresponding ketols using dimethyldioxirane. This regioselectivity is essentially determined by dipolar functionalities close to the potential reactive carbinol. These results make the reactivity of polyols with dimethyldioxirane highly predictable. | eng_Latn | 14,968 |
Polymerie 2,5-Dihydroxy-1,4-benzoquinone Transition Metal Complexes Na2(H2O)24[M2(C6H2O4)3] (M = Mn2+, Cd2+) | Abstract The isotypic compounds Na2(H2O)24[M2(C6H2O4)3] (M = Mn2+, Cd2+) form infinite net-like layers. The transition metal ion is coordinated octahedrally. The dianion of 2,5-dihydroxy-1.4- benzoquinone, consisting of two allyl systems interlinked by two long C-C distances (152-153 pm), acts as a chelating ligand. Adjacent layers are connected by hydrogen bonds. The stacking sequence of these layers, ···AAA···, leads to channels, which are filled by hydrated Na+ ions. The Na+ ions are coordinated in a distorted octahedral fashion, with neighbouring octahedra sharing common faces. | Abstract Tris(ethylenediamine)cobalt(III) cations were reacted with the clay mineral montmorillonite and were studied by DTA methods. The Co(en) 3+ 3 salt was also mechanically mixed with varying amounts of alumina or silica and DTA patterns obtained. The results of the several DTA runs were compared in order to understand more completely the type of interaction that might be taking place between the Co(en) 3+ 3 ion and the montmorillonite. | deu_Latn | 14,969 |
Synthesis of Some New Spiro Heterocycles from the Reaction of 2-Coumarylidenemalononitrile with Active Methylene and Bidentate Reagents | Abstract The reaction of 2-Coumarylidenemalononitriles 1a,b with some active methylene, bidentates and ketoketene S, S or N, S acetals affords a series of new spiro heterocyclic systems. | Novel di-bicyclo[3.1.1] and [2.2.1]heptyl and dibicyclo[3.1.1] and [2.2.1]heptenyl ketones are useful as intermediates for preparing novel polyamines useful as antimicrobial agents, as well as algae inhibitors. | eng_Latn | 14,970 |
Solid-phase synthesis of 2-aryl-3-alkylamino-1H-indoles from 2-nitro-N-(2-oxo-2-arylethyl)benzenesulfonamides via base-mediated C-arylation. | Polymer-supported 2-nitro-N-(2-oxo-2-arylethyl)benzenesulfonamides, prepared from resin-bound amines by sulfonylation with 2-nitrobenzenesulfonyl chlorides followed by alkylation with α-bromoacetophenones, represent advanced intermediates for the synthesis of different nitrogenous heterocycles. We report their application for the synthesis of 2-aryl-3-alkylamino-1H-indoles via base-mediated C-arylation reactions followed by the reduction of the C-arylated intermediates. Linear precursors for C-arylation were prepared on solid-phase support from simple, commercially available building blocks. The effects of different substituents on the amino and aryl groups were addressed. | In the title compound, C(14)H(13)Cl(2)NO(2)S, the mol-ecule is bent at the S atom with an C-SO(2)-NH-C torsion angle of -69.9 (2)°. The dihedral angle between the sulfonyl and aniline benzene rings is 44.0 (1)°. The crystal structure features inversion dimers linked by pairs of N-H⋯O hydrogen bonds. An intra-molecular N-H⋯Cl hydrogen bond is also observed. | eng_Latn | 14,971 |
Mn(III)-Catalyzed Aerobic Oxidation of 3-Alkyl-4-hydroxy-1H-pyrrol-2(5H)-ones in the Presence of 1,1-Diarylethenes. Synthesis of Stable 8-Aza-1-hydroxy-2,3-dioxabicyclo(4.3.0)nonan-7-one Framework | Twenty-two 3-alkyl-4-hydroxy-1H-pyrrol-2(5H)-ones were prepared and underwent Mn(III)-catalyzed aerobic oxidation in the presence of 1,1-diarylethenes to produce very stable crystalline 6-alkyl-8-aza-4, 4-diaryl-1-hydroxy-2,3-dioxabicyclo[4.3.0]nonan-7-ones in high yields. | During the last eight years a number of aspects of ::: amide chemistry have been studied in the Chemistry ::: Department, University of Tasmania, under the direction ::: of Dr. J. B. Polya. Acylation of amides to diacylamines ::: was investigated, and satisfactory syntheses were developed ::: for unsymmetrical diacylamines (R1 ::: .CO.NH.CO.R2; R1≠R2 ). In some cases such diacylamines, through reacylation, ::: may form mixtures of the two corresponding ::: symmetrical diacylamines. Diacylamines react with hydrazines ::: to form 1:2:4-triazoles, which are convenient ::: derivatives indicating the structure of the diacylamine. ::: With a hydrazine R.NH.NH2 an unsymmetrical diacylamine ::: of the type indicated could form 1R-3R1 -5R2 - and ::: 1R-3R2 -5R1 -1:2:4-triazole. Proving the orientations of ::: the products from a number of diacylamines seemed a ::: promising way to investigate the mechanism of this triazole ::: synthesis. | eng_Latn | 14,972 |
Synthesis and Herbicidal Activity of New 1-Alkyl-3-aryloxypyrazole-4-carboxamide Derivatives | A series of novel 1-alkyl-3-aryloxypyrazole-4-carboxamide derivatives were synthesized and their herbicidal activity and crop safety examined under flooded conditions. Introduction of an aryloxy group at the 3-position of the pyrazole ring was accomplished with a nucleophilic substitution reaction of 3-hydroxypyrazoles with halobenzenes which were activated by electron-withdrawing groups such as a nitro group. The 3-trifluoromethylphenoxy analogs provided good results. The level of activity also varied with the N-substituents of the carbamoyl group, especially the 2,4-difluorophenyl group which provided the best combination of herbicidal activity and crop selectivity. Among the compounds synthesized, N-(2,4-difluorophenyl)-1-ethyl-3-(3-trifluoromethylphenoxy)pyrazole-4-carboxamide (KPP-856) showed good herbicidal activity against various annual lowland weeds and excellent crop safety at 33 g a.i./ha. | DESCRIPTION of 4-AMINOARILDIHIDROPIRIDINAS of formula (I), the definition of Substituents characterized according to the description of a process for their preparation by reduction of 4-NITROARILDIHIDROPIRIDINA RELEVANT AND EVENTUALLY TRANSFORMATION SUBSEQUENT in group 4-aminoaryl, and their application drug. | eng_Latn | 14,973 |
Synthesis and Characterization of the trans-IO2F5(2-) Dianion | Abstract : The combination of CH3CN solutions of N(CH3)4F and a mixture of cis- and trans-N(CH3)4IO2F4 produces the novel trans-IO2F5(2-) anion. Under the given conditions, only the trans-IO2F4(-) anion acts as a fluoride ion acceptor, thus allowing the separation of isomerically pure, soluble cis-IO2F4(-) from insoluble trans-IO2F5(2-). | Abstract Bis[trinitratocerium (IV)] chromate is able to proceed oxidative deprotection of trimethylsilyl ethers in benzene under reflux conditions. Trinitratocerium(IV)chwmate dihydrate is a very sluggish oxidant for this purpose. | eng_Latn | 14,974 |
Pyrolysis of Aryl Azides. XIII. Conformational Effects on the Ability of Carbonyl as a Neighbouring Group | Our previous claim, that locking an ortho carbonyl group into a favourable conformation causes very large increases in the rate of thermolysis of aryl azides , has been reexamined. In 8-azido-5-methoxy-1-tetralone the rate advantage over an azide with a rotatable ortho acetyl group is estimated to be only 18-fold. Nevertheless, this factor is large enough to invalidate attempts to explain relative neighbouring group abilities on simple electronic effects alone. The very large rate increases we reported previously for 1-azidoacridin-g(10H)-one and 1-azidoanthracene-9,10-dione are partly due to favourable retention of conjugation in the transition state. | During the last eight years a number of aspects of ::: amide chemistry have been studied in the Chemistry ::: Department, University of Tasmania, under the direction ::: of Dr. J. B. Polya. Acylation of amides to diacylamines ::: was investigated, and satisfactory syntheses were developed ::: for unsymmetrical diacylamines (R1 ::: .CO.NH.CO.R2; R1≠R2 ). In some cases such diacylamines, through reacylation, ::: may form mixtures of the two corresponding ::: symmetrical diacylamines. Diacylamines react with hydrazines ::: to form 1:2:4-triazoles, which are convenient ::: derivatives indicating the structure of the diacylamine. ::: With a hydrazine R.NH.NH2 an unsymmetrical diacylamine ::: of the type indicated could form 1R-3R1 -5R2 - and ::: 1R-3R2 -5R1 -1:2:4-triazole. Proving the orientations of ::: the products from a number of diacylamines seemed a ::: promising way to investigate the mechanism of this triazole ::: synthesis. | eng_Latn | 14,975 |
Anilides with analgesic and antipyretic activity | Several trimethylcyclopentyl and trimethylcyclopentenyl acetanilides, mono- and di-substituted on the aromatic nucleus as well as the corresponding acyl derivatives from aniline it self and corresponding phenylacetanilides, were prepared and tested as analgesics and antipyretics. Several compounds exhibit considerable activity in some cases superior to that of acetanilide. | During the last eight years a number of aspects of ::: amide chemistry have been studied in the Chemistry ::: Department, University of Tasmania, under the direction ::: of Dr. J. B. Polya. Acylation of amides to diacylamines ::: was investigated, and satisfactory syntheses were developed ::: for unsymmetrical diacylamines (R1 ::: .CO.NH.CO.R2; R1≠R2 ). In some cases such diacylamines, through reacylation, ::: may form mixtures of the two corresponding ::: symmetrical diacylamines. Diacylamines react with hydrazines ::: to form 1:2:4-triazoles, which are convenient ::: derivatives indicating the structure of the diacylamine. ::: With a hydrazine R.NH.NH2 an unsymmetrical diacylamine ::: of the type indicated could form 1R-3R1 -5R2 - and ::: 1R-3R2 -5R1 -1:2:4-triazole. Proving the orientations of ::: the products from a number of diacylamines seemed a ::: promising way to investigate the mechanism of this triazole ::: synthesis. | eng_Latn | 14,976 |
β-Lactams from ester enolates and silylimines: An enantiospecific synthesis of monocyclic β-lactams. | Abstract Optically active 3,4-disubsutituted azetidin-2-ones have been prepared by annelation of chiral silylimines derived from (S) or (R)-lactaldehyde with the ester enolate of the ethyl 2,2,5,5,-tetramethyl-1,2,5-azadisilolidin-1-acetate (STABASE). Oxidation of the hydroxyethyl side chain on the C-4 position of the β-lactam ring, followed by Baeyer-Villiger oxidation led to the optically active (3S, 4S ) 3-amino-4-acetoxy-β-laclam. The absolute configuration of this compound was determined by elaboration of this substrate to a key intermediate in the synthesis of the antibiotic “Aztreonam”. Nucleophilic displacement of the acetoxy group led to optically active 3-amino-4-alkyl (aryl)-azetidin-2-ones. | The systematic modification of the ETA selective N-(5-isoxazolyl)benzene-sulfonamide endothelin antagonists to give ETB selective antagonists is reported. The reversal in selectivity was brought about by substitution of the 4-position with aryl and substituted aryl groups. Of all the aromatic substituents studied, the para-tolyl group gave rise to the most active and selective ETB antagonist. Larger substituents caused a decrease in both ETB activity and selectivity. A similar trend was observed by substitution at the 5-position of the N-(5-isoxazolyl)-2-thiophenesulfonamide ETA receptor antagonists. The para-tolyl group was again found to be optimal for the ETB activity and selectivity. The structural features that were found to be favorable for binding to the ETB receptor, that is, the presence of a linear, conjugated pi-system of definite shape and size, have been successfully incorporated into the design of ETB selective polycyclic aromatic sulfonamides antagonists. | eng_Latn | 14,977 |
[Research on agents with antineoplastic activity. LXIII. Anthramycin and analogous compounds. X. Synthesis of 11-phenyl-5H-pyrrolo[2,1-c] [1,4] benzodiazepine derivatives]. | Reaction between arolychlorides and 1-(2-aminobenzyl)-2-cyanopyrrole afforded the corresponding aroylamides, which were transformed by intramolecular cyclization into 11-aryl-3-cyano-5H-pyrrolo[2,1-c] [1,4] benzodiazepines. Hydrolysis of cyanoderivatives furnished the corresponding amides or acids depending on the reaction conditions. Decarboxylation and reduction of some derivatives to afford 11-aryl-5H-pyrrolo[2,1-c] [1,4] benzodiazepines and 11-aryl-3-cyano-10,11-dihydro-5H-pyrrolo[2,1-c] [1,4] benzodiazepines are described. | [Formula 1] The present invention provides a group of piperazine derivatives mesylate, and a method for the preparation of these mesylates in high yield and high purity economical way. According to the method of the present invention, synthesis of the piperazine ring and the mesylate product are combined in a single reaction step. The present invention, X is a bicyclic heterocyclic phenyl group and Y is methyl, (optionally substituted by fluorine in some cases) ethyl, cycloalkyl (3-7C) methyl, benzyl or m- phenyl benzyl in which, on the mesylate of the compound of formula (1). | eng_Latn | 14,978 |
Metal Complexes of Thiosemicarbazides | This book highlighted the methods used for the syntheses of thiosemicarbazides. These new thiosemicarbazides and their metal complexes which have not been described in the literature previously were synthesized and investigated using different analytical and spectroscopic techniques and antibacterial properties. The thiosemicarbazide ligands and their metal complexes have been isolated and characterized by elemental analysis, thermogravimetric analysis, magnetic susceptibility measurements and spectral studies. The antimicrobial and antifungal activities of ligands and their metal complexes have also been evaluated | Novel pyrazolines and benzothiazepines derivatives containing piperonal nucleus were synthesized and screened for in vitro anti-bacterial as well as anti-fungal activity. The synthesized compounds were characterized by IR, 1 H NMR and MS study. These compounds shows good to excellent bioactivities as compare with reference organism. | vie_Latn | 14,979 |
Preliminary X-ray crystallographic analysis of human salivary cystatin. | Human salivary cystatin, a thiol proteinase inhibitor, has been implicated in potential antimicrobial and antiviral functions of saliva. A variant of human salivary cystatin SN expressed and purified in an Escherichia coli expression system lacking residues 12-16 near the N-terminus (Delta12-16) has been crystallized by the vapor-diffusion technique. The crystals are of the hexagonal space group P622 and have cell constants of a = 85.41, b = 85.41, c = 131.6 A, alpha = beta = 90, gamma = 120 degrees, and contain two molecules of molecular weight 13 500 per asymmetric unit. The crystals diffract up to a resolution of 2.2 A and are suitable for X-ray diffraction analysis. | Palladium-catalyzed cross-coupling of a wide range of substituted o-(pseudo)halobenzoates and hydrazines with isocyanide insertion followed by lactamization efficiently affords 4-aminophthalazin-1(2H)-ones that are difficult to obtain regioselectively by classical methods. | eng_Latn | 14,980 |
Synthesis of 2-substituted-5-rnethylthiazolo[ 3,2-b ] -1,2,4-lriazoles and acylatcd 3-amino-2-imino-4-methyl-2-thiazolines | 3-Amino-2-imino-4-mcthyl-2-thiazoline, 1, underwent ring closure with ethyl formate, cyanogen bromide and carbon disulfide, giving moderate yields of 2-substituted-5-methylthiazolo[ 3,2-b ]-1,2,4-triazoles, II. Reaction of I-HCl with acid anhydrides (acetic, propionie, trifluoroacetic) resulted in the formation of the corresponding II compounds, whereas other anhydrides (benzoic, perfluoropropionic, perfluorobutyric) gave high yields of 3-aeylamido-2-acylimido-4-melhyl-2-thiazolines. With acid chlorides and I-HCl, in the presence of trielhylamine, mixtures of 2-acyl-irnino-3-aniino-4-methyl-2-thiazolines and 2-aeylimino-3-(diacylamido)-4-methyl-2-thiazolines are formed. Spectral characteristics are reported. | Liquid N-methyldisilazane, (SiH3)2NMe, disproportionates when mixed with ammonia or methylamine at or below room temperature to give silane, hydrogen, and chiefly involatile products. Moderate heating is necessary with pyridine, trimethylamine, or tetradrofuran. Rates of silane evolution lie in the order: NH3 > NH2Me C5H5N NMe3 > C4H8O. N-Phenyldisilazane reacts similarly, but more slowly, and the order of bases is: NH3 > NH2Me PhNH2∼ C5H5N. From the stoicheiometry of the reactions and the properties, including i.r. spectra, of the products, it appears that tertiary amines yield essentially linear oligomers with SiH3NR end-groups. Primary amines and ammonia induce amine exchange and form cross-linked polmers with NR bridging groups and chiefly NHR end-groups. A mechanism to account for these facts is proposed. Polymer derived from (SiH3)2NMe and methylamine slowly reduces gaseous methylamine to ammonia at room temperature. | eng_Latn | 14,981 |
ECO-FRIENDLY SYNTHESIS AND SPECTRAL CORRELATIONS IN SOME 1-PHENYL-3-(5-BROMOTHIOPHEN -2-YL)-5-(SUBSTITUTED PHENYL)-2-PYRAZOLINES | A series containing eight 1-phenyl-3(5-bromothiophen-2-yl)-5-(substituted phenyl)-2-pyrazoline derivatives have been synthesized by microwave assisted, solid acidic green catalyst SiO 2 -H 3 PO 4 catalyzed cyclization of 5-bromo-2-thienyl chalcones and phenyl hydrazine hydrochloride under solvent free conditions. The yields of the pyrazolines were more than 85%. The purities of these pyrazolines were checked by their physical constant, micro analysis, Infrared, Nuclear magnetic resonance and Mass spectroscopic data published earlier in literature. From the spectral frequencies, infrared n(cm -1 ) of C=N, C-S, C-Br, 1 H and 13 C NMR chemical shifts (δ, ppm) of pyrazoline ring proton, carbon and C=N carbons were assigned and correlated with Hammett substituent constants, F and R parameters. From the results of statistical analysis the effects of substituents on the spectral frequencies have been discussed. | The trianion of C60 reacts readily with the ::: commonly used electrochemical solvent dichloromethane to form ::: methanofullerenes of the type ::: C60>(CH2)n, signaling a ::: cautionary warning against the use of this solvent for electrochemical ::: studies of fullerenes and opening up a new synthetic avenue for these ::: adducts. | yue_Hant | 14,982 |
Pharmacological evidence for lack of central effects of reserpine methonitrate: a novel quaternary analog of reserpine | Background: Reserpine, an alkaloid from Rauwolfia serpentina was widely used for its antihypertensive action in the past. However, its use was reduced in later years due to its sedative and extrapyramidal symptoms. Objective: The present investigation aimed to synthesize reserpine methonitrate, a quaternary analog of reserpine and evaluate pharmacologically its central and peripheral actions in comparison to reserpine. Methods: The change in behavior of mice and rats after treatment with reserpine or reserpine methonitrate as assessed by their effects on barbiturate hypnosis, spontaneous motor activity, body temperature, avoidance of conditioned response and palpebral closure were considered to be central actions while their influence on the blood pressure of anesthetized rats was measured for their peripheral actions. Results: The results indicate that reserpine produced central depression dose-dependently as determined from the battery of tests on the behavior of mice and rats. Reserpine methonitrate at... | For a structure consisting of equal atoms, the point-atom densities of both the normal structure [\hat {Q}(r)] and the squared structure [\hat {Q}2(r)] must be identical except for a scale factor. Starting from this consideration, similar to that which led Sayre [Acta Cryst. (1952). 5, 60-65] to his well-known equation, the volume integral of the squared difference between \hat {Q}(r)/I1 and \hat {Q}2(r)/I2 must be zero, I1 and I2 being appropriate scale factors. Consequently a new figure of merit for a set of phases is derived; the method requires consideration of both triples and quadruples of reflexions with ΣHi = 0. It proves to be effective in selecting the correct phase sets for four centrosymmetrical compounds whose structures are already known. An improved expression of the tangent formula is also derived from the new figure of merit. | eng_Latn | 14,983 |
Enantioselective synthesis of 2-substituted pyrrolidinesvia domino cross metathesis/intramolecular aza-Michael addition | A highly enantioselective intramolecular aza-Michael addition with enone carbamates catalyzed by chiral Bronsted acids was developed. A domino cross metathesis/aza-Michael addition for the preparation of 2-substituted pyrrolidines or benzopyrrolidines was also explored. The reactions described here provide an efficient asymmetric protocol for enantio-enriched heterocycles, especially 2-substituted pyrrolidines. | A new all-solid-state ion-selective electrode, which is reversible to papaverine, has been constructed using the conducting polymer poly(α-naphthylamine) as an ion-to-electron transducer. The ion-selective membrane represents an ion association complex of papaverine with a silicon tungstate counteranion in the form of an electroactive substance dispersed in a PVC matrix. The stability of the electrode potential of the proposed electrode was evaluated using a ionometric technique. | eng_Latn | 14,984 |
Platinum(II) Complexes of 2,2$^\prime$-Diaminobinaphthyl | Platinum(II) complexes of R-2,2'-diaminobinaphthyl (R-dabn), [Pt(R-dabn)(H2O)2]Cl2, [Pt(R-dabn)(R-Pn)]Cl2, [Pt(R-dabn)(R-bn)]Cl2, and platinum(II) complexes of S-2,2'-diaminobinaphthyl (S-dabn), [Pt(S-dabn)(H2O)2]Cl2, [Pt(S-dabn)(S-Pn)]Cl2, and [(Pt(S-dabn)(S-bn)]Cl2 have been prepared. (R-Pn and S-Pn are, respectively R- and S isomer of 2,3-diaminobutane). R-Pn and S-bn are, respectively R and S isomer of 2,3-diaminopropane). In the vicinity of the B-absorption band region of dabn, the circular dichroism spectra of platinum(Ⅱ) complexes of R-dabn series show a positive B-band followed by a negative higher energy A-band, which is generally understood as the splitting pattern for a conformation, while the circular dichroism spectra of platinum(Ⅱ) complexes of S-dabn series show a negative B-band followed by a positive higher energy A-band in the long-axis polarized absorption region as expected for a conformation. | ABSTRACT The tomato rhizosphere isolate Pseudomonas sp. strain P482 is a member of a diverse group of fluorescent pseudomonads. P482 produces a yet unidentified broad-spectrum antimicrobial compound(s), active inter alia (i.a.) against Dickeya spp. Here, we present a nearly complete genome of P482 obtained by a hybrid assembly of Illumina and PacBio sequencing data. | eng_Latn | 14,985 |
Acidity study on some pyridazines | The tautomeric, conformational equilibrium positions, and pKa values of some pyridazine derivatives 1–17 have been examined by means of semi empirical AM1 COSMO calculations in aqueous solution (ɛ=78.4). The results obtained from the calculations have been compared with the experimental findings. | An enantiocontrolled synthesis pathway has been developed to provide formation of tricyclic amine 7, representing the ABC ring system of the complex alkaloid daphnicyclidin A (1). Our efforts describe preparation of the Z-hexahydro-(1H)-azocine 29 and cyclization to construct the novel 4-azabicyclo[5.3.2]dodecane 31. Transannular reductive amination following the deprotection of 31 gave the desired tertiary amine 7. | eng_Latn | 14,986 |
Quinazolines as inhibitors of dihydrofolate reductase. 3. Analogs of pteroic and isopteroic acids. | A series of 19 quinazoline analogs of pteroic and isopteroic acid was prepared with particular emphasis being placed upon carboxylic acid esters. Each compound was evaluated as an inhibitor of the dihydrofolate reductases from rat liver as well as from Streptococcus faecium. Several of the more potent inhibitors were found to be inactive against L1210 leukemia in mice at low dose levels and were lethal to mice at 100 mg/kg. Six compounds were also evaluated for antimalarial activity against Plasmodium berghei in mice. Three of these were found to be curative at higher levels, while the remaining compounds were found to be toxic. | During the last eight years a number of aspects of ::: amide chemistry have been studied in the Chemistry ::: Department, University of Tasmania, under the direction ::: of Dr. J. B. Polya. Acylation of amides to diacylamines ::: was investigated, and satisfactory syntheses were developed ::: for unsymmetrical diacylamines (R1 ::: .CO.NH.CO.R2; R1≠R2 ). In some cases such diacylamines, through reacylation, ::: may form mixtures of the two corresponding ::: symmetrical diacylamines. Diacylamines react with hydrazines ::: to form 1:2:4-triazoles, which are convenient ::: derivatives indicating the structure of the diacylamine. ::: With a hydrazine R.NH.NH2 an unsymmetrical diacylamine ::: of the type indicated could form 1R-3R1 -5R2 - and ::: 1R-3R2 -5R1 -1:2:4-triazole. Proving the orientations of ::: the products from a number of diacylamines seemed a ::: promising way to investigate the mechanism of this triazole ::: synthesis. | eng_Latn | 14,987 |
Trial of Abana in Cardiovascular Disorders | The herbomineral compound Abana was tried in 50 cases of cardiovascular diseases of varied aetiology. The present trial was a follow-up study for 10 weeks. Initially in all cases Abana was administered, 1 tablet t.i.d. for five weeks and then twice a day for the next 5 weeks. There were 22 cases of myocardial infarction, 10 of post-myocardial infarction angina, 5 of angina with hypertension and one of stable angina, 6 of tachyarrhythmias of different aetiology, 4 of coronary insufficiency and 2 of hypertension. The results were "Good" in 54%, "Fair" in 42% and "Poor" in 4% of cases. Abana is a valuable addition to cardiovascular therapy as an adjuvant in the management of cardiovascular disorders. | A highly enantioselective intramolecular aza-Michael addition with enone carbamates catalyzed by chiral Bronsted acids was developed. A domino cross metathesis/aza-Michael addition for the preparation of 2-substituted pyrrolidines or benzopyrrolidines was also explored. The reactions described here provide an efficient asymmetric protocol for enantio-enriched heterocycles, especially 2-substituted pyrrolidines. | eng_Latn | 14,988 |
Synthesis, characterization, and antimicrobial activities of two mononuclear metal(II) complexes with (Z)-3-hydroxy-4-(3-hydroxy-3-phenylacryloyl)phenyl benzoate | Two mononuclear complexes with a β-diketone ligand (Z)-3-hydroxy-4-(3-hydroxy-3-phenylacryloyl)phenyl benzoate (L), [CoL2(CH3CH2OH)2] (1), and [MnL2(CH3CH2OH)2] (2) were prepared. Both complexes were characterized by X-ray crystallography, confirming that the central metal(II) are coordinated by four oxygens from two L and two oxygens from two ethanols. Both complexes were assayed for in vitro antibacterial (Bacillus subtilis, Staphylococcus aureus, Streptococcus faecalis, Pseudomonas aeruginosa, Escherichia coli, and Enterobacter cloacae) activities and showed better antimicrobial activity against Gram positive strains than Gram negative strains. | OBJECT OF THIS PATENT are compounds of formula (I) or salts thereof, where R1, R (squared) are H, an aliphatic saturated or (SUBST.), Phenyl (n.), Or R1 YR (AL SQUARE) together with the nitrogen atom to which they are attached form a heterocyclic OF FORMULA 1 rING, being independently an integer of 1 to 3, R3 is H, an aliphatic saturated or (SUBST.) A REST phenyl, benzyl or phenethyl (n.), OR (squared) and R3 are together form a chain alkylene, R4 is hydrogen, an aliphatic saturated or alkoxy, and R5 is a pyrimidinyl (n.), triazinyl, triazolyl or A REST bicyclic nitrogenous heterocyclene. These compounds have valuable qualities HERBICIDES OR PLANT GROWTH REGULATORS. | eng_Latn | 14,989 |
Related triply-bridging ligands derived from triosmium dodecacarbonyl and formamidines or 2-aminopyridines | Abstract N , N ′-Dibenzyl- or diisopropyl-formamidines react with Os 3 (CO) 12 or Os 3 (CO) 10 (cyclooctene) 2 to give different types of nonacarbonyl, HOs 3 (CO) 9 (i-PrNCHN-i-Pr) and H 2 Os 3 (CO) 9 (PhCH 2 NCHNCH 2 C 6 H 4 ), the difference being in the ability of the benzyl group to be ortho -metallated. N -Benzyl-2-aminopyridine, on the other hand, gives isomers analogous to each of these clusters. | Conclusions1. The values of the moduli of elasticity of the crystal lattices (along the axis of the chain) of polyimides DFOPF and DFOB were determined by means of x-ray diffraction. They turned out to be (21±1)·103 and (19±1)·103 kgf/mm2, respectively. The compliance co-efficients γ (calculated per one recurrent bond) and the force f required for stretching a single chain in the cell by 1% were also determined on the basis of the values of EC and data of the parameters of the elementary cells.2. The values of EC and γ were calculated, making use of empirical data of the chain compliances of PMPF and PMB determined previously [1]. The experimental and calculated values of EC and γ agree with one another.3. It was shown that the comparatively high values of EC of polyimides DFOPF and DFOB, which were observed in spite of the presence of a “hinge“ oxygen atom in the recurrent bond, is explained by the specific disposition of the “hinge“ atom in the dianhydride component. | eng_Latn | 14,990 |
The molecule can be still considered conjugated , but is neither aromatic , nor antiaromatic ( because it is not planar ) . | The molecule is still conjugated , but it is not aromatic , or antiaromatic ( because it is not planar ) . | In each of the bottom three places on the circle of fifths the two enharmonic equivalents can both be written without double-sharps or double-flats and so do not classify as ` theoretical keys ' : But when a relative key is on the opposite side of the circle from its home key , then in theory modulating to that key would involve adding so many sharps or flats that double-sharps and double-flats would have to be written in the key signature . | eng_Latn | 14,991 |
What was Bozize indicted for? | Michel Djotodia took over as president and in May 2013 Central African Republic's Prime Minister Nicolas Tiangaye requested a UN peacekeeping force from the UN Security Council and on 31 May former President Bozizé was indicted for crimes against humanity and incitement of genocide. The security situation did not improve during June–August 2013 and there were reports of over 200,000 internally displaced persons (IDPs) as well as human rights abuses and renewed fighting between Séléka and Bozizé supporters. | There are many important organozinc compounds. Organozinc chemistry is the science of organozinc compounds describing their physical properties, synthesis and reactions. Among important applications is the Frankland-Duppa Reaction in which an oxalate ester(ROCOCOOR) reacts with an alkyl halide R'X, zinc and hydrochloric acid to the α-hydroxycarboxylic esters RR'COHCOOR, the Reformatskii reaction which converts α-halo-esters and aldehydes to β-hydroxy-esters, the Simmons–Smith reaction in which the carbenoid (iodomethyl)zinc iodide reacts with alkene(or alkyne) and converts them to cyclopropane, the Addition reaction of organozinc compounds to carbonyl compounds. The Barbier reaction (1899) is the zinc equivalent of the magnesium Grignard reaction and is better of the two. In presence of just about any water the formation of the organomagnesium halide will fail, whereas the Barbier reaction can even take place in water. On the downside organozincs are much less nucleophilic than Grignards, are expensive and difficult to handle. Commercially available diorganozinc compounds are dimethylzinc, diethylzinc and diphenylzinc. In one study the active organozinc compound is obtained from much cheaper organobromine precursors: | eng_Latn | 14,992 |
Draw the tructural formula for the major product(s) formed upon treating the following \ncompounds with Cl2/AlCl3\n(a) toluene, (b) nitrobenzene, (c) chlorobenzene, \n(d) acetophenone (methyl phenyl ketone), (e) phenyl acetate and \n(f) methyl benzoate. | a) Toluene and Cl2 form p-chlorotoluene and HCl in presence of AlCl3\nb) nitrobenzene + Cl2 -(AlCl3)-> m-chloro-nitrobenzene\nc) chlorobenzene + Cl2 -(AlCl3)-> p-dichlorobenzene\nd) 1-(3-chlorophenyl)ethanone\ne) 3-chlorophenyl acetate\nf) methyl 3-chlorobenzoate\n\nOrganic Chem rocks! | NaClO4 - Per Chlorate of Sodium\nNaClO3 - Sodium Chlorate\nNaClO2 - Sodium Chlorite\nNaClO - Sodium Hypo Chlorite | eng_Latn | 14,993 |
CH3-CH2-CH=C (CH3)2 + HBr----------->__________\n\na) 3-bromo-2 methylpentane\nb) 2-bromo-2-methylpentane\nc) 2-bromo-3methylpentane\nd) 1-bromo-1,1-dimethylbutane\n\n(q70) | The H will attach to the Carbon atom which is already bonded to other hydrogen atoms, in this case, to carbon,2. Bromine will bond to the other carbon, hence carbon,1.\n\nAns: d. | Synthesis of Two Potential Inhibitors of para-Aminobenzoic Acid Synthase. | nld_Latn | 14,994 |
CH3\n |\n CH3-C-NH2\n |\n H\nacid, amine, amide, ester | This compound is an amine. You can identify it by the NH2 (amine group) at the end. You did a fair job with the structure considering the limits of the text here. I am sure you realize that two of your carbons do not have the correct number of bonds. | Would the part PNO5-999AS work? I also have one that's labeled PNO5-999NOAS, that looks similar. | cat_Latn | 14,995 |
what is phenethylamine | Phenethylamine (PEA), also known as β-phenylethylamine (β-PEA) and 2-phenylethylamine is an organic compound and a natural monoamine alkaloid, a trace amine, and also the name of a class of chemicals with many members that are well known for their psychoactive and stimulant effects.pon exposure to air, it forms a solid carbonate salt with carbon dioxide. Phenethylamine is strongly basic, pK b = 4.17 (or pK a = 9.83), as measured using the HCl salt and forms a stable crystalline hydrochloride salt with a melting point of 217 °C. | o-Phenylenediamine is an organic compound with the formula C 6 H 4 (NH 2) 2. This aromatic diamine is an important precursor to many heterocyclic compounds. | eng_Latn | 14,996 |
heterocyclic compounds in dna | When naming amines according to the IUPAC system, the -e in the corresponding alkane is replaced with. -amine. Cyclic compounds that contain a nitrogen atom are called. heterocyclic compounds. What prefix is used to show that a small alkyl group is attached to the nitrogen of aniline and not to the aromatic ring. | Pyrimidine is an aromatic heterocyclic organic compound similar to pyridine. One of the three diazines (six-membered heterocyclics with two nitrogen atoms in the ring), it has the nitrogen atoms at positions 1 and 3 in the ring.he pyrimidine ring system has wide occurrence in nature as substituted and ring fused compounds and derivatives, including the nucleotides, thiamine (vitaminB1) and alloxan. | eng_Latn | 14,997 |
what are pyrimidine dimers quizlet | The major lethal lesions are pyrimidine dimers in DNA (produced by UV-B and UV-C)--these are the result of a covalent attachment between adjacent pyrimidines in one strand. This is shown here for a thymine-thymine dimer and here for a thymine-cytosine dimer. third type of spontaneous DNA damage that occurs frequently is damage to the bases by free radicals of oxygen. These arise in cells as a result of oxidative metabolism and also are formed by physical agents such as radiation. | Pyrimidine is an aromatic heterocyclic organic compound similar to pyridine. One of the three diazines (six-membered heterocyclics with two nitrogen atoms in the ring), it has the nitrogen atoms at positions 1 and 3 in the ring.yrimidine is an aromatic heterocyclic organic compound similar to pyridine. One of the three diazines (six-membered heterocyclics with two nitrogen atoms in the ring), it has the nitrogen atoms at positions 1 and 3 in the ring. | eng_Latn | 14,998 |
what are amines | Amines are organic molecules containing nitrogen and are relatives of ammonia. In amines one of the hydrogen atoms on the nitrogen is replaced with a hydrocarbon group. | amine. an organic compound containing nitrogen. biogenic amine bioamine. sympathomimetic a's amines that mimic the actions of the sympathetic nervous system, the group includes the catecholamines and drugs that mimic their actions. biogenic. 2 biogenic a's. 3 biogenic a's. 4 biogenic a's. 5 biogenic amine. 6 biogenic amine hypothesis. 7 biogenic amine hypothesis. 8 biogenic amine hypothesis. 9 biogenic amine hypothesis. 10 Biogenic amine receptor-like G-protein coupled receptor. | eng_Latn | 14,999 |
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