The invention relates to 2-penem-3-carboxylic acid compounds of the formula ##STR1## in which R.sub.a represents an organic radical bonded by a carbon atom to the ring carbon atom, a free, etherified or esterified hydroxy or mercapto group or a halogen atom, R.sub.1 represents hydrogen, an organic radical bonded by a carbon atom to the ring carbon atom, or an etherified mercapto group, and R.sub.2 represents a hydroxy group or an R.sub.2.sup.A radical that together with the carbonyl grouping --C(.dbd.O)-- forms a protected carboxyl group, and to salts of such compounds with salt-forming groups, processes for the manufacture of such compounds, pharmaceutical preparations containing compounds of the formula I with pharmacological properties, and their use. The compounds have antibiotic activity.
本发明涉及公式为##STR1##的2-青霉烷-3-
羧酸化合物,其中R.sub.a代表有机基团,通过碳原子与环碳原子结合,自由的,醚化或酯化的羟基或巯基,或卤素原子,R.sub.1代表氢,通过碳原子与环碳原子结合的有机基团,或醚化的巯基,R.sub.2代表羟基或R.sub.2.sup.A基团,与羰基--C(.dbd.O)--一起形成保护的羧基基团,以及具有盐基团的这样的化合物的盐,制备这样的化合物的过程,含有公式I的化合物的药物制剂,以及它们的用途。这些化合物具有抗生素活性。