Toward improving ketone group reduction to obtain Pentostatin product

ORGN 161

Mallikarjuna Reddy Ravi, wwang@chempacific.com, ChemPacific Corp, 6200 Freeport Centre, Baltimore, MD MD 21224, Wuyi Wang, wwang@chempacific.com, 6200 Freeport Center, ChemPacific Corp, Baltimore, MD 21224, Li Chen, lchen@chempacific.com, QC, ChemPacific Corp, 6200 Freeport Centre, Baltimore, MD 21224, and Meizheng Liu, mliu@chempacific.com, R&D, ChemPacific Corp, 6200 Freeport, Baltimore, MD.
Pentostatin is a unique nucleoside with a “fat” aglycone base. Its chemical synthesis has been exploited by Parke –Davis group, but the initial synthesis suffered from a number of drawbacks including ketone reduction. In this presentation we describe our observations on the ketone reduction by using more recently developed reduction conditions. We will delineate the roles played by metal additives, solvents and stoicheometry of the reducing agents. A discussion of the effect of sugar moiety to the stereo-selectivity outcome will be also presented.