SYNTHESIS OF AMINOACYL SUGAR DERIVATIVES AND THEIR TASTE CHARACTERISTICS. I. 2,3-DI- O-AMINOACYL DERIVATIVES OF ALKYL d-GLUCOPYRANOSIDES

Abstract

Aminoacyl derivatives of methyl α- and β-d-glucopyranosides have been synthesized in order to ascertain the structural features required for the perception of a sweet taste. 2,3-Di-O-(l-aminoacyl) derivatives of methyl α-d-glucopyranoside showed a strong sweet taste (16–35× sucrose), which decreased or disappeared when either one of the two l-aminoacyl groups was absent or substituted by a d-aminoacyl group. In the case of 2,3-di-O-(l-alanyl) derivatives of methyl d-glucopyranoside, the α-anomer was very sweet (16–25× suc.) whereas the β-anomer was not sweet. The structural prerequisite for sweetness in this group of compounds proved to be the presence of l-aminoacyl groups at C-2 and C-3, and the α-configuration at C-1. Its α-isopropyl anomer showed the highest sweetness (64× suc.), hence the increased lipophilicity is also an important criterion.

ACKNOWLEDGMENTS

The authors wish to express their thanks to Professor Sigeru Nishiyama and Dr. Kunisuke Izawa for their helpful suggestions and to Miss Satomi Yajima, for her technical assistance. They are grateful for partial support of this study by a grant from Ajinomoto Co. Inc.