Inhibitory activities of indolizine derivatives: a patent review

ABSTRACT

Introduction

Indolizines are structural isomers with indoles. Although several indole-based commercial drugs are available in the market, none of the indolizine-based drugs are available up-to-date. Natural and synthetic indolizines have a wide-range of pharmaceutical importance such as antitumor, antimycobacterial, antagonist, and antiproliferative activities. This prompted us to search and collect all possible data about the pharmacological importance of indolizine to open an avenue to the researchers in exploring more medicinal applications of such biologically important compounds.

Areas covered

The current review article covers the advancements in the biological and pharmacological activities of indolizine-based compounds during the last decade. The covered areas of this work involved anticancer, anti-HIV-1, anti-inflammatory, antimicrobial, anti-tubercular, larvicidal, anti-schizophrenia, CRTh2 antagonist’s activities in addition to enzymatic inhibitory activity.

Expert opinion

The discovery of indolizine drugs will be a major breakthrough as compared with their widely available drug-containing indole isosteres. Major work collected here was focused on anticancer, anti-tubercular, anti-inflammatory, and enzymatic inhibitory activities. The SAR study of the reported biologically active indolizines is summarized throughout the review whenever highlighted to the rationale the behavior of inhibitory action. Several indolizines with certain functions provided great enhancement in the therapeutic activities comparing with reference drugs.

KEYWORDS:

• Indolizines
• antiinflammatory
• anticancer
• anti-HIV
• antitubercular
• enzymes inhibitors

Article highlights

• Several series of indolizines have potent and selective anticancer, anti-inflammatory, antimicrobial, anti-HIV, anti-tubercular, and selective enzymatic action agents.

• Some indolizine derivatives are considered as prodrug candidates and have the potentials for phase I clinical trials due to their better activity than some reference drugs.

• Indolizine is biostere for indole which is widely common in both pharmaceuticals and approved commercial drugs.

• Structure activity relationship (SAR) study disclosed that the nature of substituents at different position of indolizines greatly affected their pharmacological activities.

• The current review article includes a collected survey during the last decade till March 2020.

• The references section includes 33 patents covering some biological topics of this review.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.