Synthesis, Structural Study and Biological Activity of Bridgehead Nitrogen Containing Triazolo-thiadiazine Derivatives

Abstract

A facile synthesis of 6,7-di-[substituted]-phenyl-3-pyridin-4-yl-5H-[1,2,4]-triazolo-[3,4-b]-[1,3,4]-thiadiazines have been carried out by reacting 4-amino-3-mercapto-5-pyridin-4-yl-4H-[1,2,4]triazole with substituted benzoins in presence of potassium hydroxide. The required 4-amino-3mercapto-5-pyridin-4-yl-4H-[1,2,4]-triazole was synthesized by reacting isoniazide with carbondisulphide and potassium hydroxide followed by the addition of hydrazine hydrate. The acetylation of triazolo-thiadiazines afforded monoacetyl derivatives. The constitution of synthesized compounds have been delineated on the basis of chemical transformation, elemental analysis, equivalent weight determination and IR, 1 H NMR spectral studies. The title compounds have been assayed for their biological activity against gram-positive as well as gram-negative microorgansms.

Synthesis and Antibacterial Activity of Novel Triazolo[4,3-a]pyrazine Derivatives

“…At the R 2 site, for the antibacterial activity of compounds, long alkyl chain groups were superior to the aromatic groups, such as compounds 1a and 1f, and the similar conclusion was also drawn by Kaur et al [31] and Pokhodylo et al [32]. Among phenyl-substituted compounds at the R 2 site, bearing electron-donating groups favored the antibacterial activity as expressed in the compounds 1d and 1i [33]. When R 2 substituent group is an aliphatic chain, it can increase the lipophilic nature of the compounds, thereby making the molecules more cell permeable [34].…”

Vision on Synthetic and Medicinal Facets of 1,2,4-Triazolo[3,4-b][1,3,4]thiadiazine Scaffold

“…Deohate et al [ 87 ] accomplished the synthesis of 6,7-disubstituted phenyl-3-pyridin-4-yl-5 H -[1,2,4]triazolo[3,4- b ][1,3,4]thiadiazines ( 116 ) and screened them for antimicrobial activity. Screening results indicated that compounds 116b , 116e , f showed highest inhibition against bacterial strains Escherichia coli , Staphylococcus aureus , and Salmonella typhi (zone of inhibition = > 21 mm) and moderate activity against Aerobacter aerogenes (zone of inhibition = 17–20 mm).…”

Synthesis, Characterization and Antimicrobial Activity of 1,2‐dihydroquinoxaline‐3‐yl‐3‐Substitutedphenyl‐1H‐pyrazole‐4‐Carbaldehyde

“…The prevalence of pyrazole cores in biologically active molecules has stimulated the need for elegant and efficient ways to make these heterocyclic lead. Pyrazole derivatives are found to possess wide spectrum of pharmacological properties such as antibacterial [11][12][13][14], antifungal [15][16][17][18][19], antimicrobial [20,21], antidiabetic [22], herbicidal [23,24], antitumor [25][26][27][28], anti-anxiety [29], and as active pharmacophore in celecoxib (as COX-2 inhibitor) [30] and sildenafil citrate [31] (as cGMP-specific phosphodiesterase type 5 inhibitor), etc.…”