Conversion of a racemic mixture of 8‐chloro‐2‐(2,6‐difluorophenylmethyl)‐2,3‐dihydro‐3‐methyl‐1,2,5‐benzothiadiazepin‐4(5h)‐one 1,1‐dioxide into a single enantiomer via a chromatographic resolution/racemization method

A simple and efficient strategy to convert the racemic mixture of 8‐chloro‐2‐(2,6‐difluorophenylmethyl)‐2,3‐dihydro‐3‐methyl‐1,2,5‐benzothiadiazepin‐4(5 H )‐one 1,1‐dioxide, a new anti‐HIV‐1 agent targeted to reverse transcriptase, into the more active ( S )‐enantiomer is described. The method utilizes repetition of the following two steps: 1) semipreparative enantioseparation by HPLC on chiral stationary phase; 2) base‐induced racemization of the less active ( R )‐enantiomer. Chirality 15:429–432, 2003. © 2003 Wiley‐Liss, Inc.