a method for separation of enantiomers of a lactam represented by formula : where n and m are each , independently , 0 , 1 , 2 , or 3 ; p is h or an n - protecting group ; and the dotted line represents an optional double bond , by liquid chromatographing the mixture on a chiral stationary phase , where said stationary phase is derivitized with at least one sugar derivative , with an eluent which comprises acetonitrile .