β-内酰胺族抗生素的研究与发展,已进入一个新阶段。临床应用的β-内酰胺族抗生素绝大多数由青霉素或头孢菌素C裂解成6-氨基青霉烷酸(6-APA)或7-氨基头孢烷酸(7-ACA) 后,再行化学改造而得[头霉素C(Cephamycin C)衍生物也可类似地合成],其中也有部分是通过青霉素的化学转化制得。由于现代发酵技术已降低了青霉素的成本,因此,将青霉素化学转化为头孢菌素类或其母核类似物已成为重要课题。青霉素(1)和头孢菌素(2)的母核,具有相同数目的硫、氮和碳原子,仅仅是与β-内酰胺环稠合的环的排列以及氧化态不同。因此在理论上,这两类抗生素化学上相互转化是可能的, β-lactam antibiotics research and development, has entered a new phase. The vast majority of clinical application of β-lactam antibiotics by penicillin or cephalosporin C after cleavage of 6-aminopenicillanic acid (6-APA) or 7-amino-cephalosporanic acid (7-ACA), then the chemical [Cephamycin C derivatives can also be similarly synthesized], some of which are also obtained by chemical transformation of penicillin. As modern fermentation techniques have reduced the cost of penicillin, the chemical conversion of penicillin to cephalosporins or their parent nuclear analogues has become an issue. The parent nuclei of penicillins (1) and cephalosporins (2), with the same number of sulfur, nitrogen and carbon atoms, are simply the arrangement of the rings fused to the β-lactam ring and the oxidation states are different. In theory, therefore, it is possible for these two classes of antibiotics to chemically interconvert,