2-Methyloctahydropyrrolo[3,4-c]pyrrole-d3 is the isotope labelled analog of 2-Methyloctahydropyrrolo[3,4-c]pyrrole (M324475); a reagent in the synthesis of novel aryl substituted urea derivatives which can exhibit antimicrobial activity against pathogenic bacteria and fungi. 2-Methyloctahydropyrrolo[3,4-c]pyrrole is also used in the preparation of 3-hydroxyquinazoline-2,4-dione antibacterial agents.