Analysis of structural features responsible for the sweetness of the sesquiterpene, hernandulcin

The relationship between sweetness and structure was studied for several analogues of the intensely sweet sesquiterpene, hernandulcin. These derivatives were prepared synthetically, and were spectroscopic and conformational analysis. With the exception of the parent substance, none of the derivatives tested proved to be sweet. Evidence gathered in this study suggests that hernandulcin binds to its putative receptor through a three-point interaction, involving the C-1 carbonyl and C-1' hydroxyl groups, and the double bond between C-4' and C-5'. In the course of a preliminary safety assessment, the 3-desmethyl derivative of hernandulcin was found to be mutagenic toward Salmonella typhimurium strain TM677.