title: Syntheses based on 1,2-secopenicillins. Part II. Preparation of 4-(3-substituted prop-2-ynylthio)azetidin-2-ones.
mesh_terms: D001384:Azetidines / Q000138:chemical synthesis*; D001385:Azetines / Q000138:chemical synthesis*; D001593:Benzyl Compounds; D008722:Methods; D010406:Penicillins
chemical_list: D001384:Azetidines; D001385:Azetines; D001593:Benzyl Compounds; D010406:Penicillins