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1.
1-(3-R-adamantan-1-yl)-2-[(triphenyl-λ5-phosphanylidene)hydrazinylidene]ethanone reacted with 4-aryl(hetaryl)-2,4-dioxobutanoic acids to give 2-{2-[2-(3-R-adamantan-1-yl)-2-oxoethylidene]hydrazinyl}-4-aryl(hetaryl)-4-oxobut-2-enoic acids which were shown to exist in solution as mixtures of Z- and E-isomeric enehydrazine tautomers. The products underwent cyclization to 3-{[2-(3-R-adamantan-1-yl)-2-oxoethylidene]- hydrazinylidene}-5-aryl(hetaryl)furan-2(3H)-ones.  相似文献   

2.
Extraction of hydrochloric and nitric acid with 1-{[2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl]-methyl}-1H-1,2,4-triazole (propiconazole) and hydrochloric acid with (RS)-1-(4-chlorophenyl)-4,4-dimethyl-3-(1H-1,2,4-triazol-1-yl-methyl)-pentan-3-ol (tebuconazole) was studied. It is established that extraction of acids proceeds with the formation of monosolvates as an exothermic process. Effective extraction constants of acids are evaluated. By means of the IR and 1H NMR spectroscopy it was shown that the protonaccepting center of tebuconazole is N4 atom of the triazole ring.  相似文献   

3.
Abstract

2,4-bis-(3,5-di-tert-butyl-4-hydroxyphenyl)-l,3-di-thioxaphosphetane (I) has been prepared by interaction of 2,4-di-tert-butyl phenol with phosphorus pentasulfide in cumene as solvent. Reactions of I with alcohols and diole are shown to proceed readily with formation of the appropriate dithiophosphonic acids:  相似文献   

4.

Dialkyl (2Z)-2-[(2,4-dinitrophenyl)hydrazinylidene]butanedioates have been synthesized by reaction of dialkyl (2Z)-2-hydroxybut-2-enedioates with 2,4-dinitrophenylhydrazine, and their structure has been studied by IR and 1H NMR spectroscopy, mass spectrometry, and X-ray analysis.

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5.

The condensation of 3-(furan-2-yl)- and 3-(thiophen-2-yl)prop-2-enals with nitro-substituted CH acids, namely ethyl nitroacetate, nitroacetone, nitroacetophenone, and nitroacetonitrile, afforded a series of geminally activated nitro dienes, 4-(furan-2-yl)- and 4-(thiophen-2-yl)-1-nitrobuta-1,3-dienes. The product structure was confirmed by NMR and IR spectroscopy.

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6.
Substituted 3-hydroxypyrazoles, which were prepared based on ethyl esters of substituted 4-(pyridin-2-ylthio)- or 4-(1,4-dihydropyridin-2-ylthio)acetoacetic acids and hydrazine hydrate, were used in the synthesis of 6-amino-4-aryl-5-cyano-3-(pyridin-2-ylthiomethyl)-2,4-dihydropyrano[2,3-c]pyrazoles. The molecular and crystal structure of 6-amino-5-cyano-3-(3-cyano-4,6-dimethylpyridin-2-ylthiomethyl)-4-(2-nitrophenyl)-2,4-dihydropyrano[2,3-c]pyrazole was established by X-ray diffraction analysis.  相似文献   

7.
Abstract

1,2,3,4-Tetrahydro-l-aryl-3,9-dioxo-2,4-diazafluorenes (2) and 1,2,3,4-tetrahydro-1-aryl-9-oxo-3-thi-oxo-2,4-diazafluorenes (3) were newly synthesized. Compounds 3 reacted with chloroacetic acid, α-bromopropanoic acid, or B-bromopropanoic acid in the presence of fused sodium acetate and acetic anhydride to give 2,3-dihydro-5-aryl-5H,6H-thiazolo[3,2-b]2,4-diazafluorene-3,6-diones (4), 2-methyl-2,3-dihydro-5-aryl-5H,6H-thiazolo[3,2-b]2,4-diazafluorene-3,6-diones (5) and 2,3-dihydro-6-aryl-6H,7H-thiazino[3,2-b]2,4-diazafluorene-4,7-diones (6), respectively.

2,3-Dihydro-2-arylmethylene-5-aryl-5H,6H-thiazolo[3,2-b]2,4-diazafluorene-3,6-diones (7) were prepared by the reaction of compounds (3) with chloroacetic acid and aromatic aldehydes in the presence of fused sodium acetate and acetic anhydride or by the reactions of (4) with aromatic aldehydes in the presence of acetic anhydride.

2-(Arylhydroazono)-5-aryl-2,3-dihydro-5H,6H-thiazolo[3,2-b]2,4-diazafluorene-3,6-diones (8) were synthesized by coupling (4) with aryldiazonium salts in the presence of pyridine.  相似文献   

8.
Reaction of 4-(2-, 3-, 4-pyridyl, or 2-quinolyl)but-3-en-2-ones with carbethoxymethylenetriphenylphosphorane and subsequent hydrolysis gives 3-methyl-5-(2-, 3-, 4-pyridyl, or 2-quinolyl)-2,4-pentadienoic acids and also 3-methyl-4-(2-, 4-pyridyl-, or 2-quinolylmethyl)but-2-en-4-olides as products of cyclization of the corresponding pentadienoic acids.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 653–656, May, 1991.  相似文献   

9.
Polarographic reduction of 4-aryl-2-(1,2-diphenyl-2-oxoethylidenehydrazino)-4-oxo-2-butenoic acids in 2-propanol-water solutions proceeds with the formation of two or three irreversible cathode waves and leads to 4-aryl-2-(1,2-diphenyl-2-hydroxyethylhydrazino)-4-hydroxybutanoic acids. The latter suffer hydrolysis with the rupture of the C2-NH bond and the formation of 4-aryl-2,4-dihydroxybutanoic acids.  相似文献   

10.
Three complexes containing bidentate N-2,3-dimethylphenylglycine, (2,3-HDPG), N-2,4-dimethylphenylglycine, (2,4-HDPG) and N-2-ethylphenylglycine, (2-HEPG) acids have been prepared and characterized. These compounds have the general formula Zn(2,3-DPG)2·2 H2O, Zn(2,4-DPG)2 and Zn(2-EPG)2·2 H2O, respectively. The structure of the complexes as inferred from their chemistries have been found to be compatible with the infrared spectral data. The thermal behaviour of these complexes has been studied from their TG, DTG and DSC diagrams obtained in a dynamic atmosphere of pure air. Heats of dehydration have been calculated from DSC curves.  相似文献   

11.
The Suzuki Pd(0)-catalyzed coupling between arylboronic acids and aryl bromides or iodides in weakly alkaline medium, previously further developed by us, has been used for regioselective preparation of 5-(2′-bromo-5′-furyl)-, 5-(2′-bromo-4′-furyl)-, 5-(2′-bromo-5′-thienyl)-, 5-(2′-bromo-4′-thienyl)-, 5-(4′-bromo-2′-thiazolyl)-, 5-(3′-bromophenyl)-, 5-(6′-bromo-2′-pyridyl)- and 5-(4′-bromo-2′-pyrimidyl)-substituted 2,4-di-t-butoxypyrimidines. In the coupling between 2,4-di-t-butoxy-5-pyrimidineboronic acid and the nine different aryl dibromides that were tried as coupling partners, only the 2,4- and 2,5-dibromothiazoles did not give satisfactory yields, 15% and 0%, respectively. The other seven aryl dibromides gave the desired 5-(bromoaryl)-2,4-di-t-butoxypyrimidines in 58-89% yield. Attempts to synthesise 2,4-di-t-butoxy-5-(2′-bromo-4′-thienyl)pyrimidine from 2-bromo-4-iodothiophene failed. Dealkylation of the 5-(bromoaryl)-2,4-di-t-butoxypyrimidines in 2.5 M hydrochloric acid gave the corresponding 5-(bromoaryl)uracils in almost quantitative yields.  相似文献   

12.
3-(2-Chloroalkyl)-2,2-dihaloaziridines were synthesized via cycloaddition of dihalocarbenes to the CN double bond of β-chloroimines. Under the action of Lewis acids or HCl, N-C3 bond cleavage occurred, giving rise to N-substituted 2,4-dichloro-3,3-dimethylbutanamides, which were further converted to 3-chloropyrrolidin-2-ones under alkaline conditions. When 2,2-dichloro-3-(2-chloro-1,1-dimethylethyl)-1-phenylaziridine was reacted with sodium methoxide, aziridine ring opening with N-C2 bond cleavage took place, leading to methyl 4-chloro-3,3-dimethyl-2-(phenylamino)butanoate.  相似文献   

13.
A multistep approach to construct novel 3-(1H-benzo[d]imidazol-2-yl)imidazolidine-2,4-diones and 3-(1H-benzo[d]imidazol-2-yl)-2-thioxoimidazolidin-4-ones from commercially available amino acids, amines, and carboxylic acids is described. Coupling of Fmoc-amino acid to resin-bound aminobenzimidazole provided following Fmoc elimination free amine. Treatment of the free amine with 1,1′-carbonyldiimidazole or 1,1′-thiocarbonyldiimidazole furnished the corresponding hydantoins and thiohydantoins via intramolecular cyclization. The desired aminobenzimidazole tethered hydantoins or thiohydantoins were isolated in good yields.  相似文献   

14.
Abstract

The zwitterionic 1:1 intermediates generated from trialkyl phosphites and dialkyl acetylenedicarboxylates are trapped by 2,4-thiazolidinedione and 5-arylidene- 2,4-thiazolidinediones to produce dialkyl 2-(2,4-dioxothiazolidin-3-yl)-3-(dialkoxyphosphoryl) succinates and dialkyl 2-(5-arylidene-2,4-dioxothiazolidin-3-yl)-3-(dialkoxyphosphoryl) succinates in good yields.

GRAPHICAL ABSTRACT  相似文献   

15.
Abstract

A mild and efficient method for the synthesis of 1-oxo-9H-thiopyrano[3,4-b]indole-3-carboxylic acids and dimerized 3-(4-carboxy-1H-3-indolyl)-2-propenoic acids via alkaline hydrolysis of 3-(rhodanin-5-yl)-1H-indole-2-carboxylic acids derivatives was elaborated. Anticancer activity screening in NCI60-cell lines assay allowed identification of 5-fluoro-3-(4-oxo-2-thioxothiazolidin-5-ylidenemethyl)-1H-indole-2-carboxylic acid methyl ester 2a with significant antimitotic activity at micromolar and submicromolar concentrations.  相似文献   

16.
2,4-Dihydroxy-3-(3,3-dichloroallyl)quinoline, the corresponding 4-mono and 2,4-dichloro derivatives, and substituted -(3-quinolyl)propionic acids were synthesized. -(2-Hydroxy-4-chloro-3-quinolyl) propiolactone was obtained from the latter.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 975–977, July, 1972.  相似文献   

17.
ABSTRACT

Each of four ganglioside GM4 and GM3 analogues containing 2- or 3-branched fatty alkyl residues in place of ceramide have been synthesized. Coupling of O-(methyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-α-D-galacto-2-nonulopyranosylonate)-(2→3)-2,4,6-tri-O-benzoyl-α-D-galactopyranosyl trichloroacetimidate (13) or O-(methyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-α-D-glacto-2-nonulopyranosylonate)-(2→3)-O-(2,4-di-O-acetyl-6-O-benzoyl-β-D-galactopyranosyl)-(1→4)-3-O-acetyl-2,4-di-O-benzoyl-α-D-glucopyranosyl trichloroacetimidate (14) with 2- or 3-branched fatty-alkyl-1-ols (9-12), prepared from the corresponding branched fatty acids by methyl esterification and reduction, using BF3Ot2 gave the corresponding ganglioside analogues (15, 17, 19, 21, 23, 25, 27, 29) in good yields, which were coverted, via O-deacylation and de-esterification, into the title compounds.  相似文献   

18.
Abstract

A new and straightforward procedure has been developed for the preparation of symmetrical and unsymmetrical 6-(N-alkyl(aryl)amino)- and 6-(N,N-bisalkyl(aryl)amino)-2,4-bis(alkyl(aryl)thio)pyrimidines. The two identical or different alkylthio groups were successfully introduced into the pyrimidine ring of 4-amino-6-hydroxy-2- mercaptopyrimidine via S-alkylation with alkyl halides, and via a nucleophilic displacement with sodium alkylmercaptides, affording the key intermediate symmetrical and unsymmetrical 2,4-bis(alkyl(aryl)thio)-6-aminopyrimidines. Subsequently, N-alkylation of the 2,4-bis(alkyl(aryl)thio)-6-aminopyrimidines with alkyl halides conveniently gave the desired products. The human anti-platelet activities of all the synthesized new compounds were also evaluated.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.  相似文献   

19.
Abstract

The insertion of fragments of sterically hindered phenols into the structure of phosphorylacetic acids hydrazides in their reactions with 3,5-di-tert-butyl-4-hydroxybenzylacetates and sterically hindered 2- and 4-hydroxybenzaldehydes has been carried out. The synthesis of 3,5-di-tert-butyl-4-benzyl derivatives of 5-[(diphenylphosphoryl) methyl]-2,4-dihydro-3H-1,2,4-triazol-3-thiones was also carried out.  相似文献   

20.
Lajunen LH  Saarinen J  Parhi S 《Talanta》1980,27(1):71-74
The protonation equilibria of 2,4-, 2,5-, 2,6- and 3,5-dihydroxybenzoic acids were studied by means of potentiometric titrations at I = 0.5 (NaClO(4)) and 25 degrees . The dimeric species H(6)L(2) and H(5)L(2) were found to form as well as the monomeric species H(p)L in the acidic solutions of 2,4- and 3,5-dihydroxybenzoic acids under the conditions studied. For the other two acids, the protonation scheme can be expressed exclusively in terms of the species H(p)L (p = 1, 2 or 3).  相似文献   

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