Chemistry of heteroanalogs of isoflavones. 16. Benzthiazole analogs of isoflavones

The reaction of a-(2-benzthiazolyl)-2, 4-dihydroxy-5-alkylacetophenones with anhydrides and chlorides of carboxylic acids yielded 3-(2-benzthiazolyl)chromones with electron-acceptor and electron-donor substituents, as well as chromones unsubstituted in the 2 -position. Their acylation, alkylation, and aminoacylation reactions and their interaction with electrophilic and nucleophilic reagents were studied.Taras Shevchenko Kiev University, Kiev 252017. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 464–471, April, 1994. Original article submitted March 5, 1994.     

Chemistry of modified flavonoids. XVIII. Thiazole analogs of isoflavones. Homologous and isomeric series

Homologous and isomeric series of thiazole derivatives of isoflavones were produced on the basis of -(4-methyl-2-thiazolyl)-2-hydroxyacetophenones. A study of -(4-methyl-2-thiazoyl)-2-hydroxyacetophenones by PMR spectroscopy showed that these compounds exist in most nonpolar and low polarity organic solvents exclusively in the ketone form, but in dimethyl sulfoxide solution both the ketone and enol forms are observed in various ratios. A simple and effective preparative method of synthesis of homologs of 3-(2-diazolyl)-chromones was developed, and their alkylation at the phenolic hydroxyl was studied. Data of biological tests of the compounds synthesized are presented.For communication 17, see [1].T. G. Shevchenko Kiev University, Kiev 252601. Translated from Khimiya Geterotsikiicheskikh Soedinenii, No. 4, pp. 505–513, April, 1995. Original article submitted March 19, 1995.     

2-[6-Alkyl-3-hetaryl-4-oxo-9,10-dihydro-4H,8H-chromeno-[8,7-<Emphasis Type="Italic">e</Emphasis>][1,3]oxazin-9-yl]acetic acids

The interaction has been studied of a series of substituted 3-hetaryl-7-hydroxychromones with amino acids and formaldehyde (reactants ratio 1: 1: 2 respectively). In the case of glycine and Het = 3-isoxazolyl the product of aminomethylation at position 8 of the chromone was obtained, and with other Het (including Het = 4-phenyl-1,2,4-triazol-3-yl) 2-[6-alkyl-3-hetaryl-4-oxo-9,10-dihydro-4H,8H-chromeno[8,7-e][1,3]-oxazin-9-yl]acetic acids were formed. With β-alanine and Het = 4-phenyl-1,2,4-triazol-3-yl the corresponding β-substituted propionic acid was synthesized, but proline did not participate in the reaction, leading to bis(6-ethyl-3-hetaryl-7-hydroxychromon-8-yl)methane. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 683–689, May, 2007.     

Chemistry of isoflavone heterocyclic analogs. 10. Synthesis of pyrimidines by recyclization of isoflavones and their heterocyclic analogs

Isoflavones and their thiazole and pyrazole analogs are recyclized into the corresponding 4-(2-hydroxyphenyl)-pyrimidine derivatives under the effect of amidines. Their PMR spectra were studied. The effects related to the formation and strength of the intramolecular hydrogen bond were examined.For Communication 9, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1542–1550, November, 1985.     

Chemistry of the heteroanalogs of isoflavones. 20. Benzimidazole analogs of isoflavones

3-(2-Benzimidazolyl)chromones with electron-donating and electron-withdrawing substituents and also chromones unsubstituted at position 2 were obtained by the reaction of alkyl--(2-benzimidazolyl)-2,4-dihydroxy-5-acetophenones with carboxylic acid anhydrides and chlorides. Reactions with cleavage and with retention of the pyrone ring were carried out.For Communication 19, see [1].Taras Shevchenko Kiev University, Kiev. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1237–1244, September, 1997.