Alternating Dependency of Cytokinin Activity on the Number of Methylene Units in ω-Phenylalkyl Derivatives of Some Purine Cytokinins and 4-Substituted Pyrido[3, 4-d]pyrimidme

抄録

ω-Phenylalkyl derivatives of N⁶-substituted adenine, N⁶-substituted adenosine and 6-alkoxypurine with odd numbers of methylenes had relatively high activity, while the corresponding 2-methyl-4-substituted-aminopyrido[3, 4-d]pyrimidines with even numbers of methylenes had high activity in an Amaranthus betacyanin test and lettuce seed germination test. These results suggest that the ω-phenyl groups of the cytokinins play a specific role for cytokinin-receptor binding and that the pyrido[3, 4-d]pyrimidines interact with a receptor in a different binding mode.