A concise asymmetric total synthesis of 18-Ar-spirotryprostatin A analogs

A series of 18-Ar-spirotryprostatin A analogs were synthesized stereoselectively from isatin via a five-step reaction sequence involving Wittig reaction, 1,3-dipolar cycloaddition, amidated ring closure reaction, hydrolyze and decarboxylation. The two one-pot reactions employed in the synthetic route resulted in high yields. The 1,3-dipolar cycloaddition reaction exhibited a diastereomeric ratio (dr) exceeding 20:1 and an enantiomeric ratio (er) reaching 90:10. Additionally, the amidated ring closure reaction achieved yields of up to 93%.