The distribution of six cytokinins [zeatin, zeatin riboside, 6-(4-hydroxy-3-methylbutylamino)purine, 6-(3-methylbut-2-enylamino)purine and its riboside, and kinetin] between aqueous buffers (pH 3.0 and 7.0) and several organic solvents was assessed and partition coefficients calculated. Purification of cytokinins from plant extracts by solvent partition methods is discussed.

ABSTRACIT he metabolism of 13Hj6-benzylamino purine was studied in presenescent and early senescent soybean (Glycine max [L.] Meff.) leaves. In both types of leaves, the metabolism was essentially the same. The principal metabolite was identified as j-(6-benzylaminopurin-9-yl)alanine by mass spectral studies, which included discharge ionization-secondary ion mass spectrometry and pulsed positive ion-negative ion-chemical ionization mass spectrometry. Conversion to this alanine conjugate was found to be inhibited 2,4-dichlorophenoxyacetic acid and 5,7-dichloroindoleacetic acid.