An Improved Process for the Preparation of Diphenylmethyl 7β-Phenylacetamido-3-hydroxymethyl-3-cephem-4-carboxylate
journal contributionposted on 17.07.2009, 00:00 by Keping Yu, Nan Sun, Shanzong Fang, Weimin Mo, Baoxiang Hu, Zhenlu Shen, Xinquan Hu
An efficient and improved process for the preparation of diphenylmethyl 7β-phenylacetamido-3-hydroxymethyl-3-cephem-4-carboxylate was developed. With the commercially available 7-aminocephalosporanic acid (7-ACA) as starting material, up to 73.5% overall isolated yield of the titled compound was synthesized in two steps via direct phenylacetylation with phenylacetyl chloride, followed by basic hydrolysis and esterification with diphenyldiazomethane. The newly developed process obviated the use of protecting groups, reduced the environmental footprint, and could be easily controlled and conveniently scaled up for this pivotal intermediate in cephalosporin chemistry.