Synthesis of 2,2-diphenylpropionate derivatives and their effects on larval growth of the silkworm

A variety of 2,2-dipheylpropionate derivatives with an amino substituent we re synthesized and their effects on larval growth of the silkworm, Bombyx m ori were examined by dietary administration, Of the compounds tested, 3-(4- ethylpiperazin-1-yl)propyl 2,2-diphenyl-propionate (3) caused significant p rolongation of the larval period. Studies on the structure-activity relatio nship indicate that a piperazine ring and the bond distances between the ni trogen atom and the ester group were important for this activity. Treatment of compound 3 delayed the increase of ecdysteroid titers in the hemolymph by 3 days compared with that of the control, which correlates with the dela y in molting.