Semi-quantitative and quantitative structure–taste relationships for carboand hetero-sulphamate (RNHSO3–) sweeteners

Abstract

Seventeen carbosulphamates (eight synthesised in this study) and 23 heterosulphamates (seven synthesised here) have been examined with a view to extending previously developed^1,2 structure–taste relationships for sulphamates (RNHSO₃^–). Measurements of defined parameters x, y, z, and V(V=xyz) for R using Corey–Pauling–Koltun space-filling models for the 17 carbosulphamates have shown that their taste can be predicted in most cases using the previously developed semi-QSAR established. Predictions made from a recent pattern-recognition method study of sulphamate taste are shown to be partially incorrect.

The heterosulphamates were also examined using CPK models and first-order molecular connectivity (¹x^v) measurements. The use of linear discriminant analysis on seven subsets of the five variables measured i.e. x, y, z, V, and ¹x^v showed that the subset, x, z, ¹x^V misclassified only three of the 23 heterocompounds, i.e. the percentage misclassified was 13%.

Mapping of the sulphamate receptor site on the basis of the measurements carried out suggests that the carbo- and hetero-sulphamates use different sites to bind. This present work brings the database of taste-assessed sulphamates reported to over 120 compounds.