The chalones 1, 14, and 26 reacted with chlorosulfonic acid to give corresponding sulfonyl chlorides 2, 15, and 27, which condensed with nucleophiles to give amino acid derivatives 3– 6, 16–18, and 28–31. Some of the corresponding methyl esters 7, 8, 19–20, and 32–34 were prepared. Hydrazinolysis of these methyl esters yielded hydrazides 9, 10, 21, 22, and 35– 36. Coupling reaction of some amino acid derivatives with amino acid methyl ester ...
