title: Microwave promoted simple, efficient and regioselective synthesis of trisubstituted imidazo[1,2-a]benzimidazoles on soluble support.
abstract: An efficient microwave-assisted and soluble polymer-supported synthesis of medicinally important imidazole-fused benzimidazoles has been developed. The protocol involves the rapid condensation of polymer-bound amino benzimidazoles with various α-bromoketones and subsequent in situ intramolecular cyclization under microwave irradiation resulting in a one pot synthesis of imidazole interlacing benzimidazole polymer conjugates. The condensed product was obtained with excellent regioselectivity. The biologically interesting imidazo[1,2-a]benzimidazoles was released from polymer support at ambient temperature. Diversity in the triheterocyclic nucleus was achieved by the different substitutions at its 2, 3, and 9 positions. The new protocol has the advantages of short reaction time, easy workup process, excellent yields, reduced environmental impact, wide substrate scope and convenient procedure.
authors.affiliation: Department of Applied Chemistry, National Chiao Tung University, Hsinchu, Taiwan, ROC.
authors.forename: Li-Hsun
authors.initials: LH
authors.lastname: Chen
authors.forename: Ya-Shan
authors.initials: YS
authors.lastname: Hsiao
authors.forename: Gorakh S
authors.initials: GS
authors.lastname: Yellol
authors.forename: Chung-Ming
authors.initials: CM
authors.lastname: Sun
mesh_terms: D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry; D014150:Antipsychotic Agents / Q000138:chemical synthesis / Q000737:chemistry; D001562:Benzimidazoles / Q000138:chemical synthesis* / Q000737:chemistry; D020650:Combinatorial Chemistry Techniques; D008872:Microwaves; D015394:Molecular Structure; D012995:Solubility; D013237:Stereoisomerism
chemical_list: D000970:Antineoplastic Agents; D014150:Antipsychotic Agents; D001562:Benzimidazoles