Phosphosuccinic acid derivatives, processes for the production thereof and pharmaceutical agents containing these compounds

A compound of formula I, ##STR24## wherein R.sup.1 and R.sup.2 are each independently selected from the group consisting of hydrogen, lower alkyl groups, C.sub.3 -C.sub.7 cycloalkyl groups and phenylmethyl groups,

• R.sup.3 and R.sup.4 are each independently selected from the group consisting of hydrogen and lower alkyl groups, or, together with the carbon atoms to which they are bound, form a five- to seven- membered carbocyclic ring,
• R.sup.5 is selected from the group consisting of (1) C.sub.3 -C.sub.6 alkenyl groups, (2) C.sub.3 -C.sub.7 cycloalkyl groups, (3) phenylalkyl groups which are unsubstituted or have at least one substituent selected from the group consisting of C.sub.1 -C.sub.6 alkyl groups, chlorine, bromine, fluorine, hydroxy groups, methoxy groups, benzyloxy groups, acetyloxy groups, carboxy groups, ethyoxcarbonyl groups, aminocarbonyl groups, methylaminocarbonyl groups, dimethylaminocarbonyl groups, cyano groups, amino groups, methylamino groups, dimethylamino groups, benzylamino groups, acetylamino groups, benzoylamino groups and amidino groups and (4) a group of formula a),
• R.sup.9 --X--alk--, wherein a)
• R.sup.9 is selected from the group consisting of hydrogen, lower alkyl groups, C.sub.3 -C.sub.7 cycloalkyl groups and phenyl groups which are unsubstituted or have at least one substituent selected from the group consisting of C.sub.1 -C.sub.6 alkyl groups, chlorine, bromine, fluorine, hydroxy groups, methoxy groups, benzyloxy groups, acetyloxy groups, carboxy groups, ethoxycarbonyl groups, aminocarbonyl groups, methylaminocarbonyl groups, dimethylaminocarbonyl groups, cyano groups, amino groups, methylamino groups, dimethylamino groups, benzylamino groups, acetylamino groups, benzoylamino groups and amidino groups,
• X is selected from the group consisting of a bond, oxygen and sulphur, and
• alk is selected from the group consisting of a bond, a methylene chain, a saturated alkylene chain with 2-6 carbon atoms and an unsaturated alkylene chain with 2-6 carbon atoms,
• and a pharmacologically acceptable salt thereof, an ester thereof or an optical isomer thereof,
• with the proviso that where
• R.sup.3 is selected from the group consisting of hydrogen and C.sub.1 -C.sub.3 alkyl groups and R.sup.4 is hydrogen;
• R.sup.5 is other than hydrogen, hydroxy groups, methoxy groups, C.sub.1 -C.sub.3 alkyl groups and phenyl groups.