申请人:Bayer Aktiengesellschaft
公开号:US05132419A1
公开(公告)日:1992-07-21
(7-APCA) having the formula (I) ##STR1## which is an important synthesis intermediate in the preparation of cephalosporin-like antibiotics, is prepared by treating a compound of the formula (II) ##STR2## in which R.sub.1 and R.sub.2 represent alkyl, aryl and aralkyl radicals, with a strong protonic acid or with a Lewis acid. Compound (II) is prepared by adding triphenylphosphine and alkali metal iodide to a compound of the formula (VI) ##STR3## then reacting with acetaldehyde in base. Compound (VI) is prepared by treating a compound of the formula (VII) ##STR4## with a base in a polar solvent at -70.degree. C. to 0.degree. C. Compound (VII) is prepared by treating a compound of the formula (VIII) ##STR5## with a chlorinating agent in an organic solvent.
具有(I)式##STR1##的化合物(7-APCA)是头孢菌素类抗生素制备中的重要合成中间体,其制备方法是用强质子酸或Lewis酸处理式(II)##STR2##的化合物,其中R.sub.1和R.sub.2代表烷基、芳基和芳烷基基团。化合物(II)的制备方法是将三苯基膦和碱金属碘加入式(VI)##STR3##的化合物中,然后在碱性条件下与乙醛反应。化合物(VI)的制备方法是在极性溶剂中,以-70℃至0℃的温度用碱处理式(VII)##STR4##的化合物。化合物(VII)的制备方法是用氯化试剂在有机溶剂中处理式(VIII)##STR5##的化合物。