THE SYNTHESIS OF SOME EPOXYALKYL BETA-C-GLYCOSIDES AS POTENTIAL INHIBITORS OF BETA-GLUCAN HYDROLASES

The treatment of tetra-O-benzyl-D-glucono-1,5-lactone with various alk enylmagnesium halides gave the intermediate lactols which, upon reduct ion (Et3SiH/BF3) and protecting group manipulation, yielded alkenyl te tra-O-acetyl-beta-D-C-glucopyranosides in good yield. These beta-D-C-g lucosides were precursors of the epoxyalkyl beta-D-G-glucopyranosides, themselves putative inhibitors of beta-glucan hydrolases. Similar add itions of Grignard reagents to per-benzylated cellobionolactone were n ot as successful in yielding epoxyalkyl beta-C-cellobiosides. The addi tion of Grignard reagents to 1,2-anhydro-3,4,6-tri-O-benzyl-alpha-D-gl ucose offers a viable alternative route to the prop-2-enyl beta-D-C-gl ucoside, but not to the but-3-enyl and pent-4-enyl counterparts. Likew ise, the addition of Grignard reagents to a 1,2-anhydro cellobiose gav e disappointing results. Preliminary results are reported for a novel approach to alkenyl beta-D-C-glucosides by the alkylation of nitrometh yl beta-D-C-glucosides.