Syntheses of cis-Zeatin and Its 9-(2-Deoxy-.BETA.-D-ribofuranosyl) Derivative. A Novel Synthetic Route to the Side Chain at C (6), and Cytokinin Activity.
Isoprenoid cytokinins are a class of naturally occurring plant signaling molecules. A series of prepared compounds derived from isoprenoid cytokinins (isopentenyladenine, trans-zeatin and cis-zeatin) with attached 2′-deoxy-d-ribose or 2′,3′-dideoxy-d-ribose at the N9 position of the purine were prepared and their biologicalactivities were examined. Different synthetic approaches were employed. The
Syntheses of cis-Zeatin and Its 9-(2-Deoxy-.BETA.-D-ribofuranosyl) Derivative. A Novel Synthetic Route to the Side Chain at C (6), and Cytokinin Activity.
cis-Zeatin (3a) and its 9-(2-deoxy-β-D-ribofuranosyl) derivative (3c) have been synthesized from N-[(1, 1-dimethylethoxy)carbonyl]glycine methyl ester (5) in 5 steps by adopting the "α-amino aldehyde/olefination" technology. The new cis-zeatin derivative (3c), its trans isomer (1c), and known trans-zeatin 9-β-D-riboside (1b) were tested for cytokinin activity in the stimulation of chlorophyll biosynthesis in etiolated cucumber cotyledons. The riboside 1b turned out to be the most active cytokinin among them, while the deoxyribosides 1c and 3c showed a marked decrease and a total loss, respectively, of cytokinin activity.