Structural resemblance of benzimidazole nucleus with purine nucleus in nucleotides makes
benzimidazole derivatives attractive ligands to interact with biopolymers of a living system. The most
prominent benzimidazole compound in nature is N-ribosyldimethylbenzimidazole, which serves as an
axial ligand for cobalt in vitamin B12. This structural similarity prompted medicinal chemists across
the globe to synthesize a variety of benzimidazole derivatives and to screen those for various biological
activities, such as anticancer, hormone antagonist, antiviral, anti-HIV, anthelmintic, antiprotozoal,
antimicrobial, antihypertensive, anti-inflammatory, analgesic, anxiolytic, antiallergic, coagulant, anticoagulant,
antioxidant and antidiabetic activities. Hence, benzimidazole nucleus is considered as a
privileged structure in drug discovery, and it is exploited by many research groups to develop numerous
compounds that are purported to be antimicrobial. Despite a large volume of research in this area,
no novel benzimidazole derived compound has emerged as clinically effective antimicrobial drug. In
the present review, we have compiled various reports on benzimidazole derived antimicrobials, classified
as monosubstituted, disubstituted, trisubstituted and tetrasubstituted benzimidazoles, bisbenzimidazoles,
fused-benzimidazoles, and benzimidazole derivative-metal complexes. The purpose is
to collate these research reports, and to generate a generalised outlay of benzimidazole derived molecules
that can assist the medicinal chemists in selecting appropriate combination of substituents around
the nucleus for designing potent antimicrobials.
