Practical synthesis of a 1 beta-methylcarbapenem, J-111,225, using 4-mercapto-2-[4-(N-methylaminomethyl)phenyl]pyrrolidine as a precursor

An effective and practical procedure for the synthesis of J-111,225 (1), a new 1 beta -methylcarbapenem, was developed using 4-mercapto-2-[4-(N-methyl aminomethyl)phenyl]pyrrolidene (2a) as a precursor. The coupling reaction o f Za with p-nitrobenzyl (PNB)-protected 1 beta -methylcarbapenem enolphosph ate 3a and successive removal of PNB group afforded J-111,225 (1) in signif icantly increased yield compared to the ordinary procedure using a C-2 side -chain thiol with amino-protective groups.