A method for separation of enantiomers of a lactam represented by formula (I): 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.