Some novel azaimidoxy compounds viz. 2-{[(4-chlorophenyl) diazenyl] oxy}-1 H-isoindole-1, 3-(2 H)-dione (Va), and 1-{[1-naphthyldiazenyl] oxy} pyrrolidine-2, 5-dione (IVc), etc. have been synthesized by a simple diazotization reaction followed by a coupling with 2-hydroxy-1 H-isoindole-1, 3 (2 H)-dione (III)/1-hydroxypyrrolidine-2, 5-dione (II) of corresponding aromatic primary amine derivatives at a suitable pH. A similar reaction with a [1, 3] thiazolo ...