Chemistry of heteroanalogs of isoflavones

Thiazole analogs of isomeric isoflavones were synthesized from -(2,4-dimethyl-5-thiazolyl)-2-hydroxyacetophenones, and their reaction with hydrazine hydrate and alkylating and acylating agents was studied. The reaction of thiazole derivatives of 7-hydroxychromone with hydrazine hydrate proceeds with opening of the pyrone ring and subsequent cyclization of the intermediate to o-hydroxyphenylpyrazole derivatives. The reaction of hydrazine hydrate with thiazole derivatives of 5-hydroxychromone, which proceeds with retention of the pyrone ring, leads to hydrazones. The structures of the new compounds were confirmed by the PMR spectra.See 1] for communication 6.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 25–28, January, 1979.