7-[2-(2-aminothiazol-4-yl)-2-(syn)-methoxyiminoacetamido]cephalosporanic acid derivatives of the formula; ##STR1## wherein R.sup.1 NH is an amino group which may optionally be protected; COOR.sup.2 is a carboxyl group which may optionally be esterified; X is oxygen, sulfur or an imino group which may optionally be substituted; B is hydrogen or a hydroxyl, amino, thiol or hydrocarbon group which may optionally be substituted, or a salt thereof, are novel, .beta.-lactamase-resistant and low-toxicity compounds which display excellent activity against a broad spectrum of microorganisms including Gram-negative bacteria such as Escherichia coli, Serratia marcescens, Proteus rettgeri, Enterobacter cloacae, Citrobacter freundii. Thus, these compounds can be used for antibacterial agents in therapeutical purpose.
公式为7-[2-(
2-氨基噻唑-4-基)-2-(同)-甲氧基亚硝基乙酰
氨基]
头孢菌素酸衍
生物;其中R.sup.1 NH是一个
氨基,可以选择性地被保护;COOR.sup.2是一个可以选择性酯化的羧基;X是氧、
硫或一个可以选择性替代的亚硝基;B是氢或一个可以选择性替代的羟基、
氨基、
硫醇或碳氢基团,或其盐,是新颖的、β-内酰胺酶抗性和低毒性的化合物,对包括大肠杆菌、马尔色葡萄球菌、雷氏变形杆菌、肠臭臭肠杆菌、弗伦德氏柠檬杆菌在内的广谱微
生物表现出优异的活性。因此,这些化合物可用于治疗用抗菌剂。