Stereoselective synthesis of four possible isomers of streptopyrrolidine

• Debendra K. Mohapatra,
• Barla Thirupathi,
• Pragna P. Das and
• Jhillu S. Yadav

Beilstein J. Org. Chem. 2011, 7, 34–39, doi:10.3762/bjoc.7.6

• )-streptopyrrolidine (2) (4R,5S)-streptopyrrolidine (3) and (4S,5S)-streptopyrrolidine (4) have been achieved in a concise and highly efficient manner via a highly stereoselective aldol type reaction with the trimethylsilyl enolate of ethyl acetate and Lewis acid mediated lactamization as the key reactions in ≈42

• (4S,5S)-streptopyrrolidine (4) in a concise and highly efficient manner via a highly stereoselective aldol type reaction and Lewis acid mediated lactamization as the key reactions. A retrosynthetic analysis for streptopyrrolidine is depicted in Scheme 1. The synthesis was initiated from D

• % yield over six steps starting from D-phenylalanine and L-phenylalanine, respectively. The absolute configuration of the natural product was shown to be (4S,5S) by comparing its spectral and analytical data with the reported values. Keywords: aldol reaction; angiogenesis; cancer; Lewis acid mediated