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1.
The synthesis, antitubercular, anti-HIV, and antitumor activity of the 4-(adamant-1-yl)thiazolyl-2-amides of 1-R-4-hydroxy-2-oxoquinoline-3-carboxylic acids have been studied. An efficient method for purifying the 4-hydroxy-2-oxoquinoline derivatives from their metal salts is proposed.  相似文献   

2.
The reaction of chloroacetamide with 2 equiv of γ-aminobutyric acid potassium salts provides a convenient method for the synthesis of substituted 4-[(2-amino-2-oxoethyl)amino]butanoic acids. Alkylation products of 2-aminoacetic and 3-aminopropanoic acid with chloroacetamide were isolated. Thermal cyclization of substituted 4-[(2-amino-2-oxoethyl)amino]butanoic acids afforded 2-(2-oxopyrrolidin-1-yl)acetamides.  相似文献   

3.
4.
The condensation of o-aminothiophenol with sulfodifluoroacetic acid led to the formation of benzothiazol-2-yl(difluoro)methanesulfonic acid whose aryldiazonium salts were converted by pyrolysis into aryl benzothiazol-2-yl(difluoro)methanesulfonates.  相似文献   

5.
dl-β-(Thymin-1-yl)alanine has been resolved into d(+) and l(?) forms. The pure d(+) form was obtained by fractional crystallisation of the (+)α-methylphenylethylamine salts of the α-N-formyl derivatives. The pure l(?) isomer was obtained on a small scale by chromatography of the same salts. The optically active amino acids and the dl-mixture were polymerised by the mixed anhydride procedure to give polymers which showed no evidence of base stacking or of interaction with polyadenylic acid. The molecular weights of the polymers were in the range 2–4 × 103. These were determined by end group assay which involved the synthesis of α-N-(2,4-dinitrophenyl)-dl-β-(thymin-1-yl)alanine as a standard.  相似文献   

6.
α-Methyl-β-(3-methylpyrazol-1-yl)-and α-methyl-β-(5-methylpyrazol-1-yl)propionic acids were synthesized by reaction of 3(5)-methylpyrazole with methyl methacrylate, followed by separation of the resulting isomeric esters and their hydrolysis. Esterification of the title acids was performed via vinyl exchange reaction with vinyl acetate in the catalytic system mercury acetate-trifluoroacetic acid.  相似文献   

7.
The reactions of pyrimidine-2-carbonitrile and 4,6-dimethylpyrimidine-2-carbonitrile with hydrazine hydrate were investigated. Intermediates in the route of successive transformations of pyrimidine-2-carbonitrile (pyrimidine-2-carbamidrazone and 1,2-bis[amino(pyrimidin-2-yl)methylidene]hydrazine) into trinuclear heterocyclic compounds, viz., symmetrical di(pyrimidin-2-yl)-1,4-dihydro-1,2,4,5-tetrazines and di(pyrimidin-2-yl)-4H-1,2,4-triazol-4-amines (potential polydentate ligands), were isolated. The oxidative dehydrogenation of di(pyrimidin-2-yl)-1,4-dihydro-1,2,4,5-tetrazines afforded the corresponding 3,6-di(pyrimidin-2-yl)-1,2,4,5-tetrazines.  相似文献   

8.
The catalytic addition of O-methyl (adamant-2-ylmethyl)phosphonite to phenylacetylene in the presence of complexes of Pd, Cu, and Ni was studied. Pd(0)-Catalyzed addition led to the preferential formation of the Markovnikov’s adduct. Copper and nickel complexes exhibit low catalytic activity in the reaction. Effect of the catalyst nature and modifying additives on chemo- and regioselectivity of the reaction was discussed.  相似文献   

9.
4-Acetoxy-2-cyclohexenone (ACH) and 2-cyclohexenone-4-yl methacrylate (CHM) were obtained from the condensation reaction of 4-bromo-2-cyclohexenone (BCH) with acetic acid and methacrylic acid using 1,8-diazabicyclo-[5,4,0]-7-undecene (DBU), respectively. Poly(2-cyclohexenone-4-yl methacrylate) ( P-1 ) containing acid-sensitive 2-cyclohexenone-4-yl group was prepared from the radical polymerization of CHM and the esterification of poly(methacrylic acid) with BCH using DBU. Furthermore, P-1 and CHM copolymers ( P-2 and P-3 ) were easily synthesized from the radical polymerization of methacrylic acid and comonomers in dimethylsulfoxide using 1 mol % of 2,2′-azobis (isobutyronitrile) followed by esterification of the resulting polymers with BCH using DBU by one-pot method. The deprotection reaction of ACH and P-1 was carried out in dichloromethane using an acid catalyst. The reaction proceeded smoothly in solution to give phenol and the corresponding carboxylic acid. Therefore, the 2-cyclohexenone-4-yl group is a useful protecting group for carboxylic acids, because the protection and deprotection reactions are very easy. In the case of polymer films, however, the acid was trapped by carbonyl group on the 2-cyclohexenone-4-yl group, and did not cause the deprotection reaction. © 1993 John Wiley & Sons, Inc.  相似文献   

10.
15, 16, and 17-Membered lactones based on the bis-3,4(indol-1-yl)maleimide framework were obtained using intramolecular esterification reaction starting from 3-(1-ω-carboxyalkyl-2,3-dihydroindol-1-yl)-4-(1-ω-hydroxyalkyl-2,3-dihydroindol-1-yl)-maleimides. 3,4-Dibromo-maleimide, ω-(2,3-dihydroindol-3-yl)alkanoic acids, and ω-(2,3-dihydroindol-3-yl)alkanoles were used as starting compounds. Substitution of Br for the substituted indolines followed by the intramolecular cyclization of O-silylated hydroxyl acids derivatives led to macrolactones that incorporated 4-(dihydroindol-1-yl)-3-(indol-1-yl)maleimide moieties. Indoline nuclei in these compounds were dehydrogenated by DDQ in refluxing toluene to give 15, 16 or 17-membered lactones 3-[(ω-3-carboxyalkylindol-1-yl)-4-(ω-hydroxyalkylindol-1-yl)maleimides. Quantum chemical calculations showed that the formation of macrolactones of smaller size (13-membered) corresponds to the higher Gibbs energy ΔG# and correlates with the absence of the target reaction product.  相似文献   

11.
Acylation of 6-methyl-N-[4-(pyridin-3-yl)pyrimidin-2-yl]benzene-1,3-diamine, 4-methyl-N-[4-(pyridin-3-yl)pyrimidin-2-yl]benzene-1,3-diamine, and N-[4-(pyridin-3-yl)pyrimidin-2-yl]benzene-1,3-diamine with maleopimaric and citraconopimaric acid chlorides, with benzotriazolyl maleopimarate afforded N-[3-(pyrimidin-2-yl)aryl]amides of maleopimaric and citraconopimaric acids. By the reaction of substituted N-arylamides of maleopimaric acid with methanesulfonic acid biologically active methanesulfonates were obtained.  相似文献   

12.
以取代的苯磺酰肼与(取代嘧啶-2-基)-氨基甲酸苯酯在非亲核性碱存在下合成了12个4-(取代嘧啶-2-基)-1-芳磺酰基氨基脲化合物5和3个5与碱形成的有机盐5as, 5bs5cs. 所有合成化合物均经过元素分析和1H NMR的结构确证. 1H NMR数据证明, 在5as5cs中, 磺酰氨基脲起到提供质子的作用.  相似文献   

13.
Potential chelating-forming ligands and reagents for heterocyclization — ethyl esters of 4-[N-(R-pyrid-2-yl)carbamoyl]-3-amino-2-cyanobuten-2-oic acids ["codimers" of cyanoacetic acid ethyl ester (EECA) and the corresponding (pyrid-2-yl) amides of this same acid) — were synthesized in two ways: by condensation of 2-dialkylborylamidopyridines (picolines) with EECA (via chelate compounds of boron) and by the reaction of EECA dimer with 2-aminopyridines (picolines).N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 2, pp. 371–376, February, 1992.  相似文献   

14.
N,N-Dialkylhydrazides of S-(4,6,7-trichloro-2,5-dihydroxy-2,3-dihydrobenzo[b]-3-furanyl)dithiocarbonic acids have been obtained by the reaction of 3,4,6,7-tetrachloro-2,5-dihydroxy-2,3-dihydrobenzo[b]furan with N,N-dialkylhydrazinium salts of N,N-dialkylhydrazides of dithiocarbonic acids. Recyclization in boiling ethanol in the presence of conc. HCl with subsequent oxidation leads to the formation of 3-N,N-dialkylamino-5-(3,5,6-trichloro-1,4-benzoquinon-2-yl)thiazoline-2-thiones. An attempt at recyclization in boiling trifluoroacetic acid led to the formation of 3-N,N-dialkylamino-5,6,8-trichloro-7-hydroxy-2,3,3a,8b-tetrahydrothiazolo[4,5-b]benzo[d]furane-2-thiones.  相似文献   

15.
Preparative method for the synthesis of lithium, sodium, cesium, and calcium salts of (E)-4-(5-arylisoxazol-3-yl)methyleneaminobutanoic, (E)-6-(5-arylisoxazol-3-yl)methyleneaminohexanoic, (E,S)-3-methyl-2-(5-arylisoxazol-3-yl)methyleneaminobutanoic, (E,S)-4-methyl-2-(5-arylisoxazol-3-yl)methyleneaminopentanoic and (E,2S,3S)-3-methyl-2-(5-arylisoxazol-3-yl)methyleneaminopentanoic acids was developed by reacting 5-phenyl(4-tolyl)isoxazole-3-carbaldehydes with amino acids like 4-aminobutyric and 6-aminocaproic acids, L-valine, L-leucine or L-isoleucine in the presence of lithium hydride, sodium methoxide, cesium carbonate or calcium hydride in boiling methanol.  相似文献   

16.
Tris(1-alkylindol-3-yl)methanes were obtained and oxidized into tris(1-alkylindol-3-yl)methylium salts. The resulting salts are more toxic to cultured tumor cells than to non-tumor ones. The cytotoxicity of tris(1-alkylindol-3-yl)methylium salts depends on the length of the substituent at the N atom of the heterocycle, increasing from an N-unsubstituted derivative toward N-butyl- and N-pentyl derivatives. A further increase in the length of the N-alkyl substituent lowers the cytotoxicity. The cytotoxicity of tris(1-alkylindol-3-yl)methylium salts for tumor cells correlates with their antibacterial and antifungal activity. Tris(1-alkylindol-3-yl)methylium salts produced a cytocide effect on Gram-positive microorganisms and the most active compounds, on Gram-negative microorganisms as well. Similar patterns of the structure—activity relationship of N-alkylated tris(indol-3-yl)methylium derivatives, which was observed for various lines of tumor cells, bacteria, and fungi, suggest the general character of the mechanisms of the death of prokaryotic and eukaryotic cells induced by these compounds.  相似文献   

17.

(E)-(3-Aryl-3-oxoprop-1en-1-yl)triphenylphosphonium bromides reacted with arylhydrazines in an acidic medium to form hydrazones, the intramolecular heterocyclization of which led to the formation of (2,5- diaryl-2,3-dihydro-1H-pyrazol-3-yl)triphenylphosphonium bromides. Under the action of hydrobromic acid, the resulting quaternary phosphonium salts produced saturated (3-aryl-3-oxopropyl)triphenylphosphonium salts.

  相似文献   

18.
3-Aryl(heteryl)-4-formylpyrazoles by condensation with malonic acid furnish 3-[3-aryl(heteryl)- pyrazol-4-yl]propenoic acids that in the presence of Raney nickel are reduced by hydrazine hydrate to 3-[3-aryl(heteryl)pyrazol-4-yl]propanoic acids. The successive conversion of both type acids into the corresponding acyl chlorides, esters, and amides was performed.  相似文献   

19.
Carboxylation of bis(pyrazol-1-yl)alkanes by oxalyl chloride was studied. It was found that 4,4′-dicarboxylic derivatives of substrates with electron-donating methyl groups and short linkers (from one to three methylene groups) can be prepared using this method. Longer linkers lead to significantly lower product yields, which is probably due to instability of the intermediate acid chlorides that are initially formed in the reaction with oxalyl chloride. Thus, bis(pyrazol-1-yl)methane gave only monocarboxylic derivative even with a large excess of oxalyl chloride and prolonged reaction duration. An alternative approach involves the reaction of ethyl 4-pyrazolecarboxylates with dibromoalkanes in a superbasic medium (potassium hydroxide–dimethyl sulfoxide) and is suitable for the preparation of bis(4-carboxypyrazol-1-yl)alkanes with both short and long linkers independent of substitution in positions 3 and 5 of pyrazole rings. The obtained dicarboxylic acids are interesting as potential building blocks for metal-organic frameworks.  相似文献   

20.
9-o- and 9-m-carboranylcarboxylic acids were used to synthesize σ-(o-carboran-9-yl)- and σ-(m-carboran-9-yl)-π-cyclopentadienyldicarbonyliron. The latter complexes, in reactions with bromine, undergo rearrangement with the cleavage of the BFe σ-bond, involving migration of the 9-o- and 9-m-carboranyl groups into the cyclopentadienyl ring, to give π-(o-carboran-9-yl)cyclopentadienyl- and π-(m-carboran-9-yl)cyclopentadienyl-dicarbonyliron bromides, respectively. A simple method to obtain these acids by the oxidation of 9-alkyl-o- and 9-alkyl-m-carboranes with CrO3 in CH3COOH has been found.  相似文献   

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