39235-77-3

Upstream product

• 64370-26-9 methyl (2R,3R)-2-(2'-benzothiazolylthio)-α-isopropylidene-4-oxo-3-phenoxyacetylaminoazetidine-1-acetate 
• 60-24-2 2-hydroxyethanethiol 
• 380412-94-2 3-methyl-2-((1R)-7-oxo-3-phenoxymethyl-(1rH,5cH)-4-thia-2,6-diaza-bicyclo[3.2.0]hept-2-en-6-yl)-but-2-enoic acid methyl ester 

Relevant academic research and scientific papers

A New Preparative Route to 3-Unsubstituted Cephalosporins from Penicillin V

p-Nitrobenzyl (2R,3R)-2-(benzothiazol-2'-yldithio)-α-isopropylidene-4-oxo-3-phenoxyacetylaminoazetidine-1-acetate (7), readily prepared from penicillin V, can be converted into the corresponding 2-allylthio compound (2) by addition of allyl bromide and sodium borohydride at a low temperature.This compound (2) on treatment with ozone, followed by cyclization with trimethyl phosphite, produces a 3H-ceph-3-em ester (4).The ester can be easily de-esterified to the free acid (1b).