Synthetic studies of carbapenem and penem antibiotics. II. Synthesis of 3-acetyl-2-azetidinones by (2 + 2) cycloaddition of diketene and Schiff bases.
It was found that (2 + 2) cycloaddition reaction of diketene with Schiff bases was effectively promoted by imidazole as a catalyst to afford 3-acetyl-2-azetidinone derivatives 4. As an application of this new method, a practical asymmetric synthesis of 4 and its conversion into (3S,4S)-4-carboxy-1-(di-p-anisylmethyl)-3-[(R)-1-hydroxyethyl]-2- azetidinone, which is a key intermediate for the synthesis of carbapenem and penem antibiotics, were accomplished.
Sasaki
A
A
Research Laboratories, Sumitomo Pharmaceuticals Co., Ltd., Osaka, Japan.
Goda
K
K
Enomoto
M
M
Sunagawa
M
M
D000900:Anti-Bacterial Agents / Q000138:chemical synthesis*; D001384:Azetidines / Q000138:chemical synthesis*; D015780:Carbapenems / Q000138:chemical synthesis*; D012545:Schiff Bases / Q000138:chemical synthesis*
D000900:Anti-Bacterial Agents; D001384:Azetidines; D015780:Carbapenems; D012545:Schiff Bases