Development of structure–taste relationships for sweet and non-sweet heterosulfamates †

Abstract

A data set of 101 hetero-(both cyclic and open chain) sulfamate sodium salts, whose taste data are known, have been assembled and divided into sweet (S) (20 compounds) and non-sweet (N) (81 compounds) categories. The data set is made up of 56 compounds reported earlier, 32 synthesised in this work and another 13 reported since the earlier publications. Using the parameters x, y and z (measured for the RNH portion of RNHSO 3 Na using CPK models) and first order molecular connectivity, 1 χ ν it has been possible to achieve a correct classification rate of approximately 65% using linear discriminant analysis (LDA): a compound is N if Ϫ3.285 ϩ 0.439x ϩ 0.662y ϩ 0.236z Ϫ 1.27 1 χ ν > 0 otherwise it would be S. Using quadratic discriminant analysis (QDA) the classification rate increased to approximately 80%. Finally a Tree-based analysis gave an 86% classification rate but performed poorly in classifying correctly the S group of compounds.

Synthesis of heterosulfamates. Search for structure-taste relationships

“…11 and for compounds 57 -101 in ref. 12. Examination of the Table shows that in a few cases there is no clear-cut predominant taste and a decision has to be made as to which category to assign the compound.…”

“…21-25 which are now taken to be non-sweet in this and in our last paper on this work. 12 In fact with such a large group of compounds moving a few compounds from the S to N categories…”

“…11 and compounds 57 -101 in ref. 12. The structures of the thirty one newly synthesized compounds presented in this current work i.e.…”

“…The mathematical techniques of linear discriminant analysis (LDA) 10,11,12 and quadratic discriminant analysis (QDA) 10,11,12 and, more recently, Tree analysis 12 have been employed in studying the data sets. The LDA and QDA analysis worsened somewhat as the size of the data set grew and thus Tree analysis was introduced to try to improve the classifications.…”

“…12 Each data set was examined using the Corey-Pauling-Koltun (CPK) parameters for the RNH portion of the heterosulfamate i.e. RNHSO 3 Na and a calculated first order molecular connectivity value (…”