Processes for the preparation of stable, crystalline cephalosporin intermediates of the formula ##STR1## wherein X is HI or HCl, and Nu and Nu.sup..sym. are certain N-containing heterocyclic rings attached via a sulfur atom or a ring nitrogen atom, respectively, which are substantially free of the .DELTA..sup.2 isomer; processes for intermediates in the preparation of the above compounds; and processes for the preparation of broad-spectrum cephalosporin antibiotics.
制备稳定、结晶
头孢菌素中间体的方法,其中 X 是 HI 或 HCl,Nu 和 Nu.sup..sym. 是通过
硫原子或环氮原子连接的某些含氮杂环,这些中间体基本不含有 .DELTA..sup.2 异构体;制备上述化合物的中间体的方法;以及制备广谱
头孢菌素抗生素的方法。