BCEAB

Chemical Name: 4-[1-[N-[Bis(4-methylphenyl)methyl]carbamoyl]-3-(2-ethoxybenzyl)-4-oxoazetidin-2-yloxy]benzoic acid
CAS No. 256410-86-3 ((S,S)-isomer)
项目整合开发状态: Preclinical
项目研究机构: Shionogi (Originator)
合成路线:Alkylation of the dianion of azetidinonecarboxylic acid (I) with 2-ethoxybenzyl bromide (II) in cold THF affords (III).Oxidative cleavage of the carboxyl group of (III) using lead tetraacetate and HOAc provides the acetate ester (IV),which is desilylated to (V) with tetrabutylammonium fluoride in THF.Azetidinone (V) is coupled with benzhydryl 4-hydroxybenzoate (VI) to yield ether (VII).Curtius rearrangement of carboxylic acid (VIII) provides isocyanate (IX).Coupling between isocyanate (IX) and azetidine (VII) gives rise to urea (X).The benzhydryl ester group of (X) is finally cleaved by treatment with trifluoroacetic acid in the presence of anisole.
📌 参考资料/链接:
参考文献标题:Monocyclic beta-lactam cpds.and chymase inhibitors containing the same
文献作者:Nakajima,M.; Kii,M.; Uenaka,M.(Shionogi & Co.Ltd.)
参考来源:EP 1099690; WO 0005204