Abstract: Pentacyclic derivatives having the general formulae (Ia), (Ib) and (Ic) ##STR1## denote: hydrogen, alkyl with 1 to 20 carbon atoms polyoxyhydrocarbyl, phenyl, phenylalkyl with 1 to 3 carbon atoms in the alkyl chain, wherein the alkyl residues or/and phenyl residues can be substituted by one or several hydroxy, halogen, sulfo, carboxy or alkoxycarbonyl groups in which alkoxy can have 1 to 4 carbon atoms;R.sup.7 denotes an alkyl group with 1 to 7 carbon atoms, substituted by at least one halogen, or denotes a carboxyalkyl group or a phenyl group which is substituted by a carboxy or alkoxycarbonyl group located at the o-position relative to the carbon atom bound to the pentacyclic ring system and by at least one halogen, wherein alkoxy can have 1 to 4 carbon atoms, or a carboxymethylene-oxy-alkyloxy group; the residues R.sup.14 and R.sup.