Synthesis and antimicrobial activity of some novel fused heterocyclic 1,2,4-triazolo [3,4-b][1,3,4] thiadiazine derivatives

Abstract

In the present investigation, the synthesis and antimicrobial evaluation of 1,2,4-triazolo [3,4-b][1,3,4] thiadiazine including different pharmacophores are aimed at. In this study, a series of 6-aryl-3- (3,4 -dialkoxyphenyl)-7H -[1,2,4]triazolo [3,4-b][1,3,4] thiadiazine (7a-7k) was synthesized by condensing 4-amino-5-(3,4-dialkoxyphenyl)-4H-[1,2,4]- triazole-3-thiol (6) with various aromatic carboxylic acids in the presence of phenacyl bromides through one-pot reaction. Eleven fused heterocyclic derivatives were successfully synthesized. The structures of these newly synthesized compounds were characterized by IR, 1H NMR and mass spectroscopic studies. All the synthesized compounds were screened for their antimicrobial evaluation. Some of the compounds exhibited promising antimicrobial activity. From the present study it may be concluded that synthesized compounds are fruitful in terms of their structural novelty and marked biological activities. These compounds could be further modified to develop potential and safer antifungal agents.

Multicomponent Efficient Synthesis of New [1,2,4]Triazolo[3,4]thiadiazines

“…The peaks of the remaining aromatic protons were observed in the usual region. 13 C NMR spectrum of 4a shows two carbons of thiadiazine ring observed at δ 55.6 and 59.1, whereas the remaining aromatic carbons were observed in the usual region. The mass spectrum of 4a exhibited [M + H] + peak at m/z 501.…”

“…2-((4-((E)-(4-Methoxybenzylidene)amino)-5-((E-2-(4methoxybenzylidene)hydrazinyl)-4H-1,2,4-triazol-3-yl)thio)-1-(4-methoxyphenyl)ethanone (6a). Colorless solid; mp 119-121°C; IR (KBr) ν max (cm À1 ): 3400 (NH stretching), 2964 (CH stretching), 1673 (C═O stretching), 1599 (C═N stretching); 1 H NMR (400 MHz, CDCl 3 ): δ 3.68 (s, 3H, OCH 3 ), 3.82 (s, 3H, OCH 3 ), 3.85 (s, 3H, OCH 3 ), 4.72 (s, 2H, CH 2 ), 6.77 (d, J = 8.0 Hz, 2H), 6.93 (d, J = 8.0 Hz, 4H), 7.28 (s, 1H), 7.73 (d, J = 8.0 Hz, 2H), 7.94 (d, J = 8.4 Hz, 2H), 8.03 (d, J = 8.4 Hz, 2H), 8.86 (d, J = 8.4 Hz, 2H);13 C NMR (100 MHz, DMSO-d 6 ): δ 191.2, 169.5, 164.3, 164.2, 161.8, 149.7, 147.7, 145.8, 132.2, 131.3, 129.7, 128.2, 126.3, 124.0, 115.2, 114.7, 114.5, 56.2, 56.1, 55.8; ESI-MS, m/z (%): 531 (M + H) + ; Anal. Calcd for C 27 H 26 N 6 O 4 S: C, 61.12; H, 4.94; N, 15.84; S, 6.04; found: C, 61.19; H, 4.98; N, 15.81; S, 6.12.1-(4-Fluorophenyl)-2-((4-((E)-(4-methoxybenzylidene) amino)-5-((E-2-(4-methoxybenzylidene)hydrazinyl)-4H-1,2,4triazol-3-yl)thio)ethanone (6b).…”

Green synthesis, molecular docking and pharmacological evaluation of new triazolo‐thiadiazepinylcoumarine derivatives as sedative‐hypnotic scaffold

“…[3][4][5][6][7][8][9][10] On the other hand, 1,3,4-thiadiazepines have been reported for their promising biological activities such as antitumor, anticonvulsant, anti-HIV, antiviral, antidepressant, antiinflammatory, and antimicrobialr. [11][12][13][14][15] During recent decades, impressive reports are archived in writing for the proficiency of triazolo-thiadiazepines as great therapeutic agents. Various derivatives of triazolothiadiazepines are found to have astounding in vitro antitubercular, [16] antimicrobial, [17,18] anti-cancer, and antiviral activity.…”

Theoretical investigation into coordination and selectivity of uranyl‐unilateral benzotriazole salophens (X = O/S) for R/S‐triadimefons

“…determined the chronic toxicity thresholds of five aquatic organisms, and used species sensitivity‐degree distribution to derive PNEC based on the reproductive adaptability of nine aquatic organisms . Derivatives of TDF‐fused heterocyclic structures also possess antitumor activity, and have many applications . Lao et al .…”

“…[36] Derivatives of TDF-fused heterocyclic structures also possess antitumor activity, and have many applications. [37] Lao et al investigated the effects of chiral stationary phases, co-solvents, column temperature and back pressure on chiral separation of TDF, and a fast analytical method through supercritical fluid chromatography was developed for enantioselective determination of TDF in soil and apple samples. [38] However, until now, an asymmetric unilateral benzotriazole thio-salophen (UBTS) and complexation of uranyl-UBTS as well as uranyl-UBTS coordinated with R/S-TDFs have not been reported.…”