Synthesis and antimicrobial activity of morpholinyl/piperazinylbenzothiazines

Abstract

Structurally diverse morpholinyl/piperazinylbenzothiazines have been synthesized in quantitative yields by the reaction of substituted 1,4-benzothiazines with morpholine/N-(2-hydroxyethyl)piperazine. 1,4-Benzothiazines were prepared by the reaction of substituted 2-aminobenzenethiols with b-ketoesters. The structures of the synthesized compounds were confirmed by their analytical and spectroscopic data. The synthesized compounds were evaluated for their antimicrobial activity against bacterial species; E. coli and Bacillus cereus. Some of the synthesized compounds have shown significant activity against microorganisms.

Ring Contraction of 2,5-Dihydrobenzo[f][1,2,5]thiadiazepine 1,1-Dioxides: Access to 4H-Benzo[b][1,4]thiazine 1,1-Dioxides

“…7 In addition, numerous benzothiazines are in clinical development as antipsychotics, analgesics, diuretics, antitussives, and antihistamines. 3,8 The corresponding S-oxidized 4H-benzo[b] [1,4]thiazine 1,1-dioxide analogues III 9−11 were first described in 1968. Since then, they have assumed a prominent role in organic synthesis, medicinal chemistry, and the chemical industry.…”

“…The structural similarity of 1,4-benzothiazines I (Figure ) to pharmacologically important 10 H -phenothiazines II has triggered considerable interest in synthetic and biological studies of this class of compounds. − 1,4-Benzothiazines I and their analogues are well documented to exhibit pharmacologically relevant activities, including sedative, anthelmintic, antiulcer, anticancer, antibacterial, and antifungal effects. − They also inhibit acetylcholinesterase (AchE), which is responsible for several neurological disorders, such as Parkinson’s and Alzheimer’s diseases . In addition, numerous benzothiazines are in clinical development as antipsychotics, analgesics, diuretics, antitussives, and antihistamines. , The corresponding S-oxidized 4 H -benzo­[ b ]­[1,4]­thiazine 1,1-dioxide analogues III − were first described in 1968. Since then, they have assumed a prominent role in organic synthesis, medicinal chemistry, and the chemical industry. , Several analogues of III have been isolated from a bryozoan .…”

One-Pot Domino Reaction: Direct Access to Polysubstituted 1,4-Benzothiazine 1,1-Dioxide via Water–Gas Shift Reaction Utilizing DMF/H2O

“…Benzothiazines, one of the privileged heterocyclic motifs, occupy an important place in organic synthesis because of their wide applications in biologically active molecules, pharmaceuticals, advanced organic materials, and as intermediates in organic synthesis (Scheme a) . Moreover, the utility of these compounds in the total synthesis of natural molecules like pseudopteroxazole solidifies their importance in synthetic versatility .…”