Two new substances, padmakastin, a glycoside and padmakastein, the corresponding aglucone have been isolated from the bark ofPrunus puddum. The properties and reactions of padmakastein indicate that it is dihydroprunetin. This has been confirmed by its oxidation to prunetin and by its preparation from prunetin by reduction. Padmakastein is the first isoflavanone to be isolated and it gives the well-known Durham test characteristic of rotenoids.