Lehman VA, Ma Y, Scheerer JR. Construction of the 4-Azafluorenone Core in a Single Operation and Synthesis of Onychine.
J Org Chem 2024. [PMID:
39014934 DOI:
10.1021/acs.joc.4c01298]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2024]
Abstract
This study describes the synthesis of the 4-azafluorenone core in a single operation using readily available starting materials. Condensation of an amidrazone with ninhydrin intercepts an intermediate 1,2,4-triazine derivative, which engages norbornadiene in a merged [4 + 2]/bis-retro[4 + 2] sequence to deliver the azafluorenone core. The tricyclic core established in this manner was elaborated to onychine, the simplest natural product in the 4-azafluorenone alkaloid family.
Collapse