The heterocyclic pyrollidine rings are very common in natural products and are the leading components of alkaloids.1 They are important synthetic components of HIV reverse transcriptase enzyme and inhibitors of substance P neurotransmitters.(2,3) They also possess antibacterial and antiamnestic activities.4,5 The heterocyclic imidazole derivatives are considered as an influential synthetic precursor in drug designing and discovery process.6,7 They are known to possess antimicrobial, antitumor and anti-inflammatory activity and they also inhibit MAP kinase p38 protein.8 The fused heterocycle viz. pyrrolo-imidazole (Py-Im) (Fig.1) derivatives have been established as powerful partial agonists of the 1A adrenoceptor (GPCR known as adrenergic receptor) and have shown better response over the 1B, 1D, and 2A receptor subtypes. The fused Py-Im derivative also inhibits the JNK (c-Jun-N-terminal kinase) pathway which is the fascinating drug target for several neurodegenerative disorders. Considering the various biological activites associated with it synthesis of Py-Im derivatives (1H-pyrrolo[1,2-a]imidazole) has been taken up. Efforts are taken to use greener approach for the synthesis of Py-Im derivatives.
Fig. 1. Pyrrolo-imidazole derivatives