Review Article Volume 10 Issue 2 - December 2020 DOI: 10.19080/OMCIJ.2020.09.555784 Organic & Medicinal Chem IJ Copyright © All rights are reserved by Sandile B Simelane Organic & Medicinal Chem IJ 10(2): OMCIJ.MS.ID.555784 (2020) 001 Organic and Medicinal Chemistry International Journal ISSN 2474-7610 Benzopyran-Core as an Antimycobacterial Agent Sandile B Simelane 1 *, Paseka T Moshapo 2 and Raban W Masuka 3 1 Department of Chemistry, Faculty of Science and Engineering, University of Eswatini, Eswatini 2 Department of Chemical Sciences, University of Johannesburg, South Africa 3 University of Zimbabwe, School of Pharmacy, Mt Pleasant Drive, Zimbabwe Submission: October 18, 2020; Published: December 01, 2020 * Corresponding author: Sandile B Simelane, Department of Chemistry, Faculty of Science and Engineering, University of Swaziland, Private Bag 4, Kwaluseni, Swaziland Introduction Tuberculosis (TB) is a chronic and potentially fatal disease caused by Mycobacterium tuberculosis (Mtb) complex. The Mtb complex is made up of bacilli from M. tuberculosis, M. bovis, M. mungi, M. caprae, M. canettii, M. africanum, M. microti and M. pinnipedii [1-3]. Known as “white plague”, Mtb was first isolated and identified by Robert Koch in 1882 [4]. In 2017, TB caused an estimated 1.3 million deaths among HIV-negative people and there were an additional 300 000 deaths from TB among HIV-positive people [5]. One-third of the world’s population is affected with Mtb and an estimated 10 million people developed TB in 2017, with 488 000 of them affected by multi drug-resistant TB (MDR- TB). Multi drug-resistant TB is defined as tuberculosis whose bacteria are resistant to isoniazid (INH) and rifampicin (RIF). If the bacterium is resistant to isoniazid and rifampicin as well as any of the floroquinolones, it is called extensively drug resistant TB (XDR-TB) [6]. Abstract Tuberculosis (TB) is one of the world’s most deadly infectious diseases, causing 1.2 million deaths in 2018. TB is the leading cause of death from a single infectious agent, ahead of HIV/AIDS. The African continent bears the highest global TB/HIV burden and over 50% of TB cases in sub-Saharan Africa are co-infected with HIV. With an estimated 1.7 billion people (23% of the world’s population) with latent TB infection, there is an urgent need to develop drugs that will eradicate or control the disease. Moreover, the emergence of multi-drug resistant tuberculosis (MDR-TB) and extensively drug resistant tuberculosis (XDR-TB) have accelerated the need for new antitubercular agents with novel biological targets and different mechanism of action. Among the wide spectra of heterocyclic compounds, benzopyran derivatives have displayed diverse biological applications. Found in many natural products, this scaffold together with its synthetic analogs has intrigued medicinal chemists to explore its applicability as anti-TB drugs. To further intensify research in this area, there is need to gather the latest information on benzopyrans as antimycobacterial agents. This review presents an overview of recent developments (2000 -2018) in anti-TB applications of benzopyrans, both the synthetic analogs and isolated natural products. The objective of this review is to focus on active benzopyran analogs and structure activity relationship (SAR) analysis. We envisage that this review will be helpful in rational design of potent, less toxic benzopyran-based anti-TB drug candidates. Keywords: Mycobacterium tuberculosis; Anti-TB agents; Medicinal chemistry; Benzopyran Abbreviations TB: Tuberculosis; HIV/AIDS: Human immunodeficiency virus infection/acquired immune deficiency syndrome; MDR-TB: multi-drug resistant tuberculosis; XDR-TB: extensively drug resistant tuberculosis; SAR: structure activity relationship; Mtb: Mycobacterium tuberculosis; INH: isoniazid; RIF: rifampicin; ETB: ethambutol; PZA: pyrazinamide; SADC: Southern African Development Community; CYP1B1: Cytochrome P450 Family 1 Subfamily B Member 1; MIC: minimum inhibitory concentration; FtsZ: filament temperature-sensitive mutant Z; MABA: micro-plate alamar blue assay; SI: selectivity index; sm-DNA: salmon milt-Deoxyribonucleic acid; A-T: adeninethiamide; MmpL3: Mycobacterial membrane protein Large; BCG: Bacillus Calmette-Guérin; MRA: microdilution resazurin assay; L-J: Lowenstein-Jensen; DprE1: decaprenylphosphoryl- β-D-ribose 2′-epimerase; TAACF: tuberculosis antimicrobial acquisition and coordinating facility; ATP: Adenosine triphosphate; HadAB: β-hydroxyacyl-ACP dehydratase