Preparation of the Key Intermediate in the Synthesis of GV143253A: The Anti-MRSA/E Injectable Trinem
作者:Paolo Maragni、Mario Mattioli、Roberta Pachera、Alcide Perboni、Bruno Tamburini
DOI:10.1021/op020024l
日期:2002.9.1
GV143253A is a broad-spectrum injectable beta-lactam belonging to the class of trinem antibiotics. A key intermediate (3S,4R)-3-[(1R)-1-(tert-butyldimethyl- silyloxy)ethyl]-4-[-(6'R)-2'-[(E)(pyrid-4yl)methylene]-1'-oxocyclohex-6'-yl]azetidin-2-one (10) was identified and synthesized via different enolate coupling approaches, using enol ether, lithium, sodium, magnesium, tin, zinc, zirconium, and titanium enolates. Among these approaches, the synthesis of (3S,4R)-3-[(1R)-1-(tert-butyldimethylsilyloxy)ethyl]-4-[-(6'R)-2'-[(E)-(pyrid-4yl)-methylene]-1'-oxo- cyclohex-6'-yl]azetidin-2-one (10) via a titanium enolate offered advantages in terms of greater diastereoselectivity, higher yield, robustness, and isolation of intermediates and was superior to the method previously used for preparing large quantities of drug substance for early development studies.