Synthesis of β-Lactam from Acyl(Arylcarbamoyl)-S,S-bis(alkylketene) Dithioacetal: Revised Structure of the Product from Thermal Cyclization of Acyl(Arylcarbamoyl)-S,S-bis(alkylketene) Dithioacetal - Choi, Eun Bok; Yon, Guy Hwan; Lee, Hyeon Kyu; Yang, Hee Cheol; Yoo, Chung Youl; Pak, Chwang Siek (Synthesis, 2003)