The present invention relates to compounds of formula I ##STR1## wherein R.sup.1 is a group selected from 2-, 3-, and 4-hydroxyphenyl, 3-nitrophenyl, and 3-fluoro-4-hydroxyphenyl; as well as readily hydroyzable esters thereof, pharmaceutically acceptable salts of said compounds and hydrates of the compounds of formula I and of their esters and salts.
本发明涉及公式I的化合物,其中R.sup.1是从2-、3-和
4-羟基苯基、3-
硝基苯基和3-
氟-
4-羟基苯基中选择的基团;以及这些化合物的易
水解酯、药学上可接受的盐以及公式I化合物及其酯和盐的
水合物。