Formylation of N-substituted phenyl succinimides was carried out by using Vilsmeier-Haack reagent which formed
2,5-dichloro-3,4-diformyl (N-substituted Phenyl) pyrroles (III) compounds. Compounds (III) was treated with
ethylene glycol in presence of PTSA to get dioxolane derivatives (IV) which on further treatment with hydrazine
hydrate formed compound (V) described in (Scheme-I). The synthesis of Schiff bases (VI) by treating 2 moles of
substituted aromatic primary amines with 1 mole of compound (III). This compound (VI) on treatment with 2 moles
of thioglycolic acid formed corresponding 4-thiazolidinone derivatives (VII) of 2,5-dichloro-3,4-diformyl (Nsubstituted
phenyl) pyrroles. (Scheme-II).