The C-3 sidechain of azetidinones related to SCH 48461 was modified by
introducing a hydroxyl group at the 1' position. This led to the disc
overy of the cis azetidinone 2c, which had improved CAI activity. Comp
ound 2c was prepared using a selective reduction and silane mediated d
ebromination to control the relative stereochemistry of the three cent
ers. Copyright (C) 1996 Elsevier Science Ltd