NATURAL-ABUNDANCE H-2 NUCLEAR-MAGNETIC-RESONANCE STUDY OF THE ORIGIN OF RASPBERRY KETONE

The site-specific natural abundance deuterium distribution of raspberr y ketone 3 obtained through a variety of methods has been determined t hrough H-2 NMR spectroscopy. This technique provided a means of distin guishing between ''natural'' raspberry ketones biogenerated from 4-hyd roxybenzalacetone (2), obtained from 4-hydroxybenzaldehyde of extracti ve botanical origin and acetone produced by sugar fermentation by redu ction using baker's yeast and other microorganisms, and other raspberr y ketone samples obtained in different ''non-natural'' ways. Of natura l origin is also a commercial sample obtained in an unspecified manner . A mechanistic interpretation has been proposed to explain the differ ence of site-specific deuterium content between the examined samples.