7－（香豆素－3－甲酰胺）－3－［1－（取代）吡啶基甲基］头孢菌素的合成

Synthesis of 7-(coumarin-3-formamido)-3-[1-(un)substituted-pyridylmethyl]-cephalosporin

目的：探讨３＇－乙酰氧基被Ｎ－亲核试剂取代的反应条件、分离精制方法和新头孢菌素的体外抗菌活性。方法：７－（香豆素－３－甲酰胺）头孢菌素在ＮａＩ或ＫＳＣＮ的存在下与吡啶和β－甲基吡啶反应，产物用大孔吸附树脂及葡聚糖凝胶柱层析分离。结果：合成的二个新头孢菌素化合物，由红外光谱、元素分析和核磁共振谱确证其化学结构。体外抗菌试验表明，对某些革兰阴性菌有一定的抑菌作用。结论：该反应中加入大量的ＮａＩ可缩短反应时间并减少杂质。大孔吸附树脂可有效地将头孢菌素与无机盐分离。

To investigate the reaction conditions in which 3-acetoxy is replaced by N-nucleophile,the isolation and purification methods and the in vitro antibacterial activities of the new cephalosporins. METHOD:7-(coumarin-3-formamido)-cephalosporin was reacted with pyridine and β-methylpyridine in the presence of NaI or KSCN;the prodcts were isolated by macroporous resin and sephadex column chromatogrophy. RESULTS :Two new cephalosporins were comfirmed by IR,elemental analysis and 1HNMR. The in vitro antibacterial tests showed that these compounds possessed some activities against Gram-positive bacteria.CONCLUSION:The addition of a large quantity of NaI makes the reaction time shortened and the impurities reduced.The macroporous resin can isolate effectively cephalosporin from impurities.