The angiotensin converting enzyme inhibitor (-)-A
58365A (
1) was synthesized by a process based on the [3 + 2]-cycloaddition reaction of aphenylsulfonyl-substituted
intermediate. The starting material for this process was prepared from
L-pyroglutamic acid andinvolved using a diazo-phenylsulfonyl-substituted pyrrolidine imide. Treatment of the diazoimide with Rh
2(OAc)
4 in the presence of methylvinyl ketone afforded a 3-hydroxy-2-pyridone derivative which was subsequently converted to the ACE inhibitor in six additional steps.