Prominent Aspects of Electroorganic Synthesis in β-Lactam Chemistry
摘要:
AbstractThe potentiality of electrolysis procedures in the penicillin‐cephalosporin conversion as well as in the direct transform of penicillins into oxazolineazetidinones as an intermediate for the preparation of the sulfur‐free analogues of cephalosporins are discussed. Especially, a chemoselective electrolytic chlorination of methyl group of 3‐methyl‐3‐butenoate moiety of thiazolineazetidinone derived from penicillins, a direct synthesis of 3′‐thiosubstituted cephalosporins from the thiazoline‐azetidinones, an improved synthesis of exomethylenecephams, an efficient route to 3‐chloromethyl‐Δ3‐cephems, electrochemical S‐S bond fission of 4‐(2‐benzothiazolyldithio) azetidinones, a direct transformation of penicillins into oxazoline‐azetidinones by chloride salt‐promoted electrolysis, and a versatile intermediate for new β‐lactam antibiotics are presented.
Process for preparing oxazolineazetidinone derivatives
申请人:Otsuka Kagaku Yakuhin Kabushiki Kaisha
公开号:US04379032A1
公开(公告)日:1983-04-05
This invention provides a process for preparing an oxazolineazetidinone derivative represented by the formula ##STR1## (wherein R.sup.1 represents hydrogen atom, alkyl group, alkenyl group, substituted or unsubstituted aralkyl group, substituted or unsubstituted aryl group, or substituted or unsubstituted aryloxymethyl group, R.sup.2 represents free or protected carboxyl group and R.sup.3 represents hydrogen atom or methoxy group) from a penicillin derivative represented by the formula ##STR2## wherein R.sup.1, R.sup.2 and R.sub.3 are as defined above.
AbstractThe potentiality of electrolysis procedures in the penicillin‐cephalosporin conversion as well as in the direct transform of penicillins into oxazolineazetidinones as an intermediate for the preparation of the sulfur‐free analogues of cephalosporins are discussed. Especially, a chemoselective electrolytic chlorination of methyl group of 3‐methyl‐3‐butenoate moiety of thiazolineazetidinone derived from penicillins, a direct synthesis of 3′‐thiosubstituted cephalosporins from the thiazoline‐azetidinones, an improved synthesis of exomethylenecephams, an efficient route to 3‐chloromethyl‐Δ3‐cephems, electrochemical S‐S bond fission of 4‐(2‐benzothiazolyldithio) azetidinones, a direct transformation of penicillins into oxazoline‐azetidinones by chloride salt‐promoted electrolysis, and a versatile intermediate for new β‐lactam antibiotics are presented.