Synthesis of triazolo[4,3-b] [1,2,4,5]tetrazines and triazolo[3,4-b][1,3,4] thiadiazines using chitosan as heterogeneous catalyst under microwave irradiation

Abstract

A novel approach to the synthesis of triazolo [4,3-b][1,2,4,5]tetrazines 5a-f and triazolo [3,4-b] [1,3,4]thiadiazines 10a-g has been developed via reactions of 4-amino-5-methyl-1,2,4-triazole-3(2H)-thione 1 with hydrazonoyl halides 2a-f and 8a-g, respectively using chitosan as a basic catalyst under microwave irradiation. The structure of the products was established based on elemental and spectral analyses. Further evidence for the assigned structure of the products is based on alternative synthesis. Also the mechanism of the studied reactions was discussed.

Green Biocatalyst for Ultrasound-Assisted Thiazole Derivatives: Synthesis, Antibacterial Evaluation, and Docking Analysis

“…New thiazole derivatives 4a – f were obtained by subjecting equimolar amounts of thiosemicarbazone derivative 1 to an equivalent quantity of hydrazonoyl halides 2a – f ,,,, in the presence of Cs or TCsSB, as depicted in Scheme . Thin-layer chromatography (TLC) was used to monitor the progress of all of the reactions.…”

“…Method A: A mixture of 2-(2-oxo-1,2-diphenylethylidene) hydrazine-1-carbothioamide 1 (0.283 g, 1 mmol) and either hydrazonoyl halides 2 ,,,, or 2-bromo-1-arylethan-1-ones 5 ,,, (1 mmol each) was prepared and then 15 mol % Cs was added. This mixture was exposed to ultrasonic waves at a frequency of 40 kHz and a power of 250 W for a duration between 15 and 50 min at a temperature of 35 °C.…”

“…Continuing our commitment to green chemistry research − and recognizing the biological significance of thiazole derivatives, − this study aimed to harness the catalytic properties of TCsSB to efficiently synthesize novel thiazole derivatives using an eco-friendly and sustainable approach. The study not only successfully synthesized these compounds but also evaluated their potential as antibacterial agents and drug candidates, providing valuable insights into their pharmacological properties and binding interactions with a target protein.…”

Mechanochemical Synthesis and Molecular Docking Studies of New Azines Bearing Indole as Anticancer Agents

“…In this respect, choosing the reaction solvent, catalyst, and technique based on green chemistry protocols (GCPs) is of the utmost importance [33][34][35][36][37][38][39][40]. It is also vital to avoid the creation of unwanted or harmful byproducts by developing dependable, sustainable, and environmentally friendly synthesis processes [41][42][43]. The advantages of green chemistry protocols (GCPs) were harnessed by pharmaceutical production and implemented all (or most) of GCPs as far as practicable.…”

Microwave-Assisted One Pot Three-Component Synthesis of Novel Bioactive Thiazolyl-Pyridazinediones as Potential Antimicrobial Agents against Antibiotic-Resistant Bacteria

“…Chitosan, a biocompatible and biodegradable naturally occurring polysaccharide, is a copolymer containing both glucosamine and N-acetylglucosamine units. It can be used as a heterogeneous phase transfer basic biocatalyst in heterocyclic syntheses, such as enantioselective syntheses of asymmetric products with chiral center(s) [ 25 , 26 ], Michael addition reactions [ 27 , 28 , 29 ], as well as transition metal support for the preparation of heterogeneous catalysts [ 30 ]. The presence of amino groups is responsible for the basic nature of chitosan.…”