[Synthesis of (3-2H)-and (3-3H)-cianidanol]

In order to study the metabolism of cianidanol (I), [3-2H]-(I) and [3-3H]-(I) were synthesized. (I) was benzylated and then oxidized with DMSO-Ac2O to give 2R-3',4'5,7-tetrabenzyl-cianidan-3-one (III). (III) was reduced with NaB2H4 or NaB3H4, and then debenzylated to give [3-2H]-(I) or [3-3H]-(I). [3-2H]-(I) was obtained with the over all yield of 21% from NaB2H4. In the other hand, [3-3H]-(I) was obtained with the over all yield of 23% from NaB3H4.