A one-pot synthesis for the preparation of 1,4-disubstituted 2-oxoazetidine-3-carboxylic acid amides was developed. 5-[(N-substituted-amino)(hydroxy)methylene] Meldrum’s acids act as a source of ketenes that react with aldimines in boiling toluene to give β-lactams with a retro-amide side chain.
                                    开发了一种一步法合成1,4-二取代2-氧代氮杂环丁-3-羧酰胺的方法。5-[(N-取代
氨基)(羟基)亚甲基]梅尔德伦酸作为烯酮源,与沸腾
甲苯中的
亚胺反应,得到具有逆转酰胺侧链的β-内酰胺。