SEARCH Articles Figures Tables A,/?-Unsaturated y-butyrolactams A,p-unsaturated y-butyrolactam A-methylene-y-butyrolactams Butyrolactam complexes Butyrolactames Butyrolactams Butyrolactams Butyrolactams formation Y-Butyrolactam Y-butyrolactame Y-butyrolactams