New oxathiino- and dithiino-aminoacetic acids of the formula: ##STR1## in which A represents oxygen or sulphur, together with their racemic forms, their optically active forms and mixtures thereof, their reactive derivatives and their acid addition salts, are valuable intermediates for the preparation of therapeutically active derivatives, in particular cephalosporin derivatives of the formula: ##STR2## where R is hydrogen or acetoxy.
新的氧代和
硫代氧
噻吩-和二
噻吩-
氨基
乙酸的
化学式为:##STR1## 其中A代表氧或
硫,包括它们的外消旋型,光学活性型和它们的混合物,它们的反应性衍
生物和它们的酸加成盐,是制备治疗活性衍
生物的有价值中间体,特别是
头孢菌素衍
生物的
化学式为:##STR2## 其中R为氢或乙酰氧。