Synthesis of (-)-Monanchoradin A and (-)-Crambescin A2 392 Based on a Cyclization-Carbonylation-Cyclization Cascade

Takuya Tsukamoto; Keisuke Takahashi; Natsuki Murase; Kyoka Someya; Fujino Sakata; Tianci Yue; Taichi Kusakabe; Keisuke Kato

doi:10.1021/acs.orglett.4c03158

Synthesis of (-)-Monanchoradin A and (-)-Crambescin A2 392 Based on a Cyclization-Carbonylation-Cyclization Cascade

Org Lett. 2024 Oct 14. doi: 10.1021/acs.orglett.4c03158. Online ahead of print.

Authors

Takuya Tsukamoto¹, Keisuke Takahashi¹, Natsuki Murase¹, Kyoka Someya¹, Fujino Sakata¹, Tianci Yue¹, Taichi Kusakabe¹, Keisuke Kato¹

Affiliation

¹ Faculty of Pharmaceutical Sciences, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan.

PMID: 39400067
DOI: 10.1021/acs.orglett.4c03158

Abstract

Syntheses of guanidino alkaloids (-)-monanchoradin A and (-)-crambescin A2 392 are described. The key feature of the syntheses is the cyclization-carbonylation-cyclization cascade of the optically active propargyl guanidine. The bicyclic guanidino cores bearing an asymmetric center and ester or carboxylic acid functionality were constructed in a single step. The carboxylic acid was then converted to (-)-monanchoradin A and (-)-crambescin A2 392.