| 摘要 |
<p>1464793 Cephalosporin derivatives MEIJI SEIKA KAISHA Ltd 5 April 1974 [16 April 1973 12 May 1973 29 Nov 1973 (4) 28 Dec 1973 (4)] 15163/74 Heading C2C Novel compounds I (R<SP>1</SP> is aryloxy, aralkoxy, 1-4C alkoxy, 1-4C alkoxy-1-4C alkoxy, or halo; R<SP>2</SP> and R<SP>3</SP> are H, halo, methyl or halomethyl; Q is acet oxy, azido or -SY; Y is a heterocyclic group and n is 1 or 2) are prepared by (1) reacting cephalosporin C with to give I where Q is acetoxy; (2) reacting a compound I in which Q is acetoxy with a nucleophilic reagent R<SP>4</SP>H where R<SP>4</SP> is an azido group or SY to give the corresponding compound I where Q is azido or SY. The compounds I may be reacted with a carboxy-protecting reagent in the presence of an acid-binding agent to give the corresponding protected derivatives. These may then be reacted with an iminohalogenating agent to produce the corresponding imindhalide derivatives. There are then reacted with an alcohol to give the iminoether derivatives. On hydrolysis there iminoether derivatives give the corresponding 7-amino-cephem derivatives. Prior to hydrolysis the iminoether derivatives may be acylated; after hydrolysis this gives the 7- acylamino-cephem derivatives.</p> |
