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, and intermediates in, the preparation of the above compounds; and processes for the preparation of broad-spectrum cephalosporin antibiotics.
                            公式为##STR1##的稳定的、结晶的
头孢菌素中间体,其中X为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,分别基本上不含.DELTA..sup.2异构体;上述化合物的制备过程和中间体;以及广谱
头孢菌素抗生素的制备过程。