Summary: Synthesis and Partial Biological Evaluation of a Small Library of
Maarten H. D. Postema,* Jared L. Piper, Lei Liu, Jie Shen, Marcus Faust, and
Department of Chemistry, Wayne State University, Detroit, Michigan 48202
Received January 30, 2003
The synthesis of a small library of differentially-linked -C-disaccharides has been carried out
through the use of a radical allylation-RCM strategy. Acids 6 were prepared by Keck allylation of
a suitable carbohydrate-based radical precursor, followed by oxidative cleavage of the formed alkene.
Dehydrative coupling of these acids with the known olefin alcohol 5 then gave the precursor esters
7 in excellent yield. Methylenation of the esters 7 was followed by RCM and in situ hydroboration-
oxidation of the formed glycals to furnish the protected -C-disaccharides 10 in good overall yield.
Five examples were then deprotected and screened for their efficacy as enzyme inhibitors of
-glycosidase and against several solid-tumor cell lines for in vitro differential cytotoxicity.
The preparation of C-glycoside-based derivatives is a
fairly mature field2 and has seen the use of interesting
chemistry for the attachment of a variety of carbon-based
groups to the anomeric carbon atom of carbohydrates.