Synthetic Strategies of Benzothiazines: A Mini Review

Abstract

Benzothiazine is a heterocyclic compound consisting of a benzene ring attached to the 6- membered thiazine ring. The benzothiazines constitute the group of heterocyclic compounds as they have found a variety of industrial uses and show promise as herbicides. Besides this, benzothiazines play an important role in the field of drug discovery as they have the potential to act as drug candidates for the treatment of a large number of diseases including, cancer, vasorelaxant, diabetic, hypertension, mycotic infection and microbial infection. The presence of nitrogen-sulphur axis and similarity in the structure with phenothiazine drugs help the benzothiazines to act as drugs for the treatment of a number of diseases. Herein, we represent different synthetic strategies for the simple and multi-component synthesis of benzothiazine heterocyclic derivatives. The strategies mostly involve the use of 2-aminothiophenol, 1, 3-dicarbonyl compounds or α-haloketones. In almost all the strategies, the potential yields have been obtained.

Switchable Synthesis of Benzothiazoles, Benzothiazines and Benzothiazepines through the Reaction of Hetareno[e]pyrrole‐2,3‐Diones with o‐Aminothiophenol

“…Hetareno[ e ]pyrrole‐2,3‐diones (1 H ‐pyrrole‐2,3‐diones fused at the [ e ]‐side to a heterocycle) are powerful polyelectrophilic substrates for the divergent synthesis of heterocyclic compounds [10,11] . Obviously, the use of o ‐aminothiophenol can result in the synthesis of all three types of N,S‐heterocycles [12–22] . We currently have a few non‐systematic data about the use of this binucleophile in reactions with hetareno[e]pyrrole‐2,3‐diones, [23–25] despite its promise.…”

“…[10,11] Obviously, the use of o-aminothiophenol can result in the synthesis of all three types of N,S-heterocycles. [12][13][14][15][16][17][18][19][20][21][22] We currently have a few non-systematic data about the use of this binucleophile in reactions with hetareno[e]pyrrole-2,3diones, [23][24][25] despite its promise.…”

2,1-Benzothiazine – (quinolin/thiophen)yl hydrazone frameworks as new monoamine oxidase inhibitory agents; synthesis, in vitro and in silico investigation

“…1). 26,27 In continuation of our efforts to search for new bioactive synthetic compounds, [28][29][30] we herein report the synthesis of new 2,1-benzothiazine 2,2-dioxide analogues and evaluation of their monoamine oxidase (MAO A and MAO B) inhibitory potential. To validate the results, in silico docking studies have been conducted to assess the binding interaction of the synthesized compounds inside the active site of enzyme.…”

A Bioinspired Synthesis of 1,4-Benzothiazines by Selective Addition of Sulfur Nucleophiles to ortho-Quinones

“…Benzothiazines are a privileged class of heterocycles which are commonly found in pharmaceuticals and natural pigments (Figure ). − 1,4-Benzothiazines in particular are components of biologically active molecules that exhibit a wide range of pharmacological properties, including antibiotic, antiemetic, antipsychotic and antihypertensive activity, to name a few. − Correspondingly, the synthesis of benzothiazines has garnered significant attention from the synthetic community, and has resulted in a number of notable advancements. ,, Commonly employed strategies include condensation reactions between β-diketones and 2-aminobenzenethiols, or transition-metal catalyzed cross-coupling reactions between alkynes and aryl isothiocyanates . While effective, the general utility of these methods is hindered by the limited commercial availability of 2-aminobenzenethiols, or the requirement for prefunctionalization of starting materials.…”

“…4−7 Correspondingly, the synthesis of benzothiazines has garnered significant attention from the synthetic community, and has resulted in a number of notable advancements. 4,8,9 Commonly employed strategies include condensation reactions between β-diketones and 2-aminobenzenethiols, 10 or transition-metal catalyzed cross-coupling reactions between alkynes and aryl isothiocyanates. 11 While effective, the general utility of these methods is hindered by the limited commercial availability of 2-aminobenzenethiols, or the requirement for prefunctionalization of starting materials.…”