SYNTHESIS AND COMPARATIVE CYTOKININ ACTIVITIES OF N-(PURIN-6-YL)-D-AMINO AND N-(PURIN-6-YL)-L-AMINO ACID METHYL-ESTERS

Six pairs of enantiomeric N-(purin-6-yl)amino acid methyl esters were synthesized andtested for their cytokinin activities by three bioassay systems, the growth of tobacco callus, the seed germination of lettuce and the fresh weight increase of excised radish cotyledons.L-(-)-Antipodes were as a whole more active than the corresponding 0-(+)-isomers in thetobacco callus and seed germination tests, whereas an uniform tendency was not observed inthe radish cotyledon expansion. The discussions were focused on the effects on the biologicalresponse of configurational arrangements around the asymmetric center at a-position to theadenine ring and on species difference of cytokinin receptor molecules. © 1978, by the Agricultural Chemical Society of Japan.