Synthesis of macrolides containing an azine or hydrazide fragment via successive tishchenko disproportionation and [1 + 1]-condensation

Eight potentially useful 15-, 17-, 20-, and 22–25-membered macrolides having an azine or hydrazide fragment were synthesized starting from L-menthol, tetrahydropyran, and 4-methyltetrahydropyran via [1 + 1]-condensation of hydrazine hydrate and some dicarboxylic dihydrazides with 7-oxooctyl 7-oxooctanoate, 3-methyl-7-oxooctyl 3-methyl-7-oxooctanoate, and (3R)-3,7-dimethyl-6-oxooctyl (3R)-3,7-dimethyl-6-oxooctanoate obtained by the Tishchenko reaction from 7-oxo-, 3-methyl-7-oxo, and (3R)-3,7-dimethyl-6-oxooctanals, respectively.