Synthesis of the Enediyne Aglycon (±)-Calicheamicinone
作者:Ian Churcher、David Hallett、Philip Magnus
DOI:10.1021/ja9801543
日期:1998.4.1
Synthesis of the Antitumor Agent Aglycon (±)-Calicheamicinone Using an <i>o</i>-Quinone Monoketal Strategy
作者:Ian Churcher、David Hallett、Philip Magnus
DOI:10.1021/ja982125y
日期:1998.10.1
Commercially available 5-methoxysalicylic acid 16 was converted into the o-quinone monoketal 21, which was attached to the enediyne 22, resulting in 23. After protection of the tert-alcohol 24 and conversion of the ester 25 to aldehyde 28, treatment with LiN(TMS)2 gave a 1:4 mixture of the 12α- and 12β-ols 29 and 30, respectively. Oxidation of the mixture 29/30 followed by DIBAL-H reduction resulted