专利号:US-4592865-A 优先权日:1976-08-09 标 题 :Azetidinone intermediates for cephalosporin analogs 发明人:NARISADA MASAYUKI; ONOUE HIROSHI; TSUJI TERUJI; NISHITANI YASUHIRO; YOSHIOKA MITSURU; HAMASHIMA YOSHIO; NAGATA WATARU 权利人:SHIONOGI & CO 摘要:Intermediates of the following formula are useful for the synthesis of 1-oxacephalosporins. Their preparation from penicillins and the transformation process to make 1-oxacephalosporins are disclosed. The compounds are of the formula: wherein A is amino or a selected acylamino; COB is carboxy or a selected protected-carboxy; X is halogen or the group OR in which R is a group represented by following formulas: CH2CCH, CH2CCNu, CH2CHCH2, +TR wherein Nu is a selected nucleophilic group; R1 is a group of the following formula: in which Hal is halogen or alkylsulfonyloxy and R2 is alkyl or aryl; and Y is hydrogen or methoxy; with the proviso that when R is propargyl or 2-oxopropyl and R1 is A is in the 3 alpha -configuration and Y is 3 beta -hydrogen or A is in the 3 beta -configuration and Y is 3 alpha -methoxy.
专利号:CH-641183-A5 优先权日:1976-08-09 标 题:SYNTHESIS OF OXACEPHALOSPORINES.