Therapeutic evolution of benzimidazole derivatives in the last quinquennial period

Highlights

• Benzimidazole: nitrogen containing bicyclic heterocyclic ring with diverse pharmacological activities.

• Benzimidazole derivatives reported in the last quinquennial period have been discussed.

• Various bioactivities such as anti-cancer, anti-microbial, antiviral and others have been highlighted.

• A brief outline on the Structure activity relationship (SAR) study has been discussed.

• This review will be helpful for medicinal chemists in designing future drugs.

Abstract

Benzimidazole, a fused heterocycle bearing benzene and imidazole has gained considerable attention in the field of contemporary medicinal chemistry. The moiety is of substantial importance because of its wide array of pharmacological activities. This nitrogen containing heterocycle is a part of a number of therapeutically used agents. Moreover, a number of patents concerning this moiety in the last few years further highlight its worth. The present review covers the recent work published by scientists across the globe during last five years.

Introduction

The chemistry of benzimidazole (Fig. 1) has been an interesting field of study since decade. Benzimidazole is a moiety that contains benzene and a heterocyclic imidazole ring. It is one of the most promising moieties that is present in many clinically useful drugs [1]. Its derivatives are of wide interest because of their various biological activities and clinical applications [2]. Benzimidazole moiety fulfills the minimum structural requirements that are common for anti-inflammatory compounds [3], [4]. It has been reported that many molecules containing benzimidazole moiety have significant anti-inflammatory as well as analgesic activity [5]. Scientists from worldwide have reported remarkable activity against fungi and bacteria [6]. In addition, the benzimidazole-substituted compounds have antiviral [7], anthelmintic, antiproliferative [8], [9], anti-hypertensive [10], H3 antagonistic [11], human glucagon receptor antagonistic [12], male contraceptive [13] and anti-infective [14] activities. These molecules also inhibit chemokine receptor (CXCR3) [15], interleukin 2-inducible T cell kinase (ITK) [16] and lymphocyte tyrosine kinase (Lck) [17]. 1-H Benzimidazole and its simple derivatives have also been claimed to prevent stomach damage caused by inflammation inhibitors [18]. N-containing benzimidazole derivatives have well known biological activities such as proton pump inhibitor (Omeprazole) [19], antihelminthic (Albendazole) [20], antidopaminergic (Domperidone) [21] and antipsychotic (Pimozide).

This moiety can be traced in a number of well established drugs belonging to different categories with diverse therapeutic activities. Such drugs are enlisted in Table 1.

Numerous patents published on this moiety are given in Table 2.