Preparation of alkyl alpha- and beta-D-glucopyranosides, thermotropic properties and X-ray analysis

Monohydrates of heptyl to decyl alpha-D-glucopyranosides as obtained from p roduct mixtures of the Fischer glucosylation were crystallized from water a t the Krafft point. The results of the single-crystal X-ray analysis of anh ydrous alpha anomers and their monohydrates provide for a better understand ing of crystal formation and stability of their hydrates. The preparation o f alkyl beta-D-glucopyranosides-without concomitant formation of alpha anom ers as by-products-has been described. The thermotropic properties have bee n investigated for the alpha compounds and their monohydrates, and for the beta-D-glucopyranosides. (C) 1998 Elsevier Science Ltd. All rights reserved .