Enantiospecific and diastereoselective synthesis of 4,4-disubstituted-3-amino-2-azetidinones, starting from D-serine

Abstract A strategy for the preparation of 4,4-disubstituted-3-amino-2-azetidinones, which are useful intermediates for the synthesis of analogues of monosulfactam Tigemonam, was developed. It employs D-serine as chiral starting material and involves, as key steps, the diastereoselective addition of organometal compounds to ketones 9 and the stereospecific cyclization of tertiary alcohols 7 to the β-lactams 6 .