A New Route to Synthesis of 3,6-Diaryl-1,2,4- triazolo [ 3,4-b ] 1,3,4-oxadiazoles

Various 1,2,4-triazoles and 1,3,4-oxadiazole derivatives have been reported to possess diverse biological activities.In addition to above biological activity, we coupled these two rings together to get 1,2,4-triazolo[3,4-b] 1,3,4-oxadiazole derivatives. This ring system was first reported in 1961[1] and synthesized in 1971.     

Synthesis and electrochemical properties of 2,6-bis（6-aryl-[1,2,4]- triazolo[3,4-b][1,3,4]-thiadiazole-3-yl）pyridines

By the condensation of 2,6-bis（4-amino-5-mercapto-[1,2,4]-triazoles-2）pyridine with aromatic acid in the presence of phosphorus oxychloride. Compounds of 2,6-bis（6-aryl-[1,2,4]-triazolo[3,4-b][1,3,4]-thiadiazole-3-yl）pyridines were synthesized. Their structures were confirmed by IR, ^1H NMR spectroscopies and elemental analysis. Their electrochemical behavior and cyclic voltammogram also were be studied. The results showed that they have high ionization potentials and good affinity.     

Phase Transfer Catalyzed Synthesis and Antibacterial Activity of Water-soluble S-Triazolo[3,4-b][1,3,4]thiadiazoles Containing Piperazine Group

6/3-（4-Chlorophenyl）-s-triazolo[3, 4-b][1, 3, 4]thiadiazoles （2,a-e） and （Sa-e） were synthesized respectively by intermolecular cyclization of 5-aryl / 4-chlorophenyl-4-amino-3- mercapto-1, 2, 4-triazoles （la-e） and （4） with 4-chlorobenzoic acid / aryl acids, which were condensed with piperazine under phase transfer catalyst TBAB to yield the corresponding free bases of monopiperazine derivatives and followed to form water-soluble salts （3a-e） and （6a-e） with hydrochloric acid in good yields. The in vitro biological results showed that piperazine group conjugated with the above fused heterocycles played an important role in antibacterial activity. The structures of novel compounds were confirmed by IR, ＇H NMR, MS and elemental analysis.     

Synthesis and Crystal Structure of 3,6-Bis（4-methyl-1,2,3-thiadiazol-5-yl）-1,2,4-triazolo[3,4-b][1,3,4]thiadiazole

The compound 3,6-bis(4-methyl-1,2,3-thiadiazol-5-yl)-1,2,4-triazolo[3,4-b][1,3,4] thiadiazole(C9H6N8S3,Mr = 322.40) has been synthesized by the reaction of 4-amino-3-(4-methyl-1,2,3-thiadiazolyl)-5-mercapto-1,2,4-triazole with 4-methyl-1,2,3-thiadiazol-5-carboxylic acid and phosphorus oxychloride,and its structure was characterized by IR,1H NMR,EI-MS,elemental analysis and single-crystal X-ray diffraction.The crystal of the title compound belongs to monoclinic,space group C2/c with a = 2.0053(4),b = 1.3081(3),c = 1.0556(2) nm,β = 112.69(3)°,Z = 4,V = 2.5548(9) nm3,Dc = 1.676 g/cm3,μ = 0.582 mm-1,F(000) = 1312,R = 0.0546 and wR = 0.1523.X-ray analysis indicates that all rings are essentially planar in this molecule,and an intermolecular hydrogen bond C(9)-H(9)…N(2) and weak intramolecular interactions between S(1)…N(7),S(3)…N(1) and S(2)…N(4) are observed.     

Synthesis of 3,6-Disubstituted 5,6-Dihydro-s-triazolo [3,4-b]-1,3,4-thiadiazolidines through the Intramolecular Mannich Reaction

３－取代基－４－氨基－５－巯基－１，２，４－三唑在微量酸催化下与取代芳香醛经分子内Ｍａｎｎｉｃｈ反应合成了２９个新的３，６－二取代－５，６－二氢－ｓ－三唑并［３，４－ｂ］－１，３，４－噻二唑啉类化合物，其结构经元素分析、ＩＲ和１ＨＮＭＲ进行确证，并讨论了反应的立体选择性。     

Synthesis and Antibacterial Activity of 8-Substituted Phenyl-1-pyridin-3-yl-5H-bis[1,2,4]triazolo[3,4-b;4′,3′-d][1,3,4] thiadiazines

1,2,4-Triazole derivatives, such as 1, 2, 4-triazolo[3, 4-b]thiadiazoles and 1, 2, 4- triazolo [3,4-b]thiadiazolines, as potent antibacterial agents have been widely investigated1-4. Chemically, their structures mainly focus on bi-fused heterocycles, but tri-fused derivatives have not been reported. In continuing our previous works5-8 on finding better antibacterial agents, we herein reported the synthesis and pharmacological evaluation for completely new class of compounds 4a~e with antibacte…     

A convenient strategy for the synthesis of 3,5-diaryl-1,2,4-thiadiazoles: oxidative dimerization of arylthioamides using CC–DMSO in PEG-400

Abstract  

An inexpensive and effective preparative protocol for the highly efficient synthesis of structurally diverse 3,5-diaryl-1,2,4-thiadiazoles at ambient temperature with 2,4,6-trichloro-1,3,5-triazine (CC) and DMSO in polyethylene glycol 400 (PEG-400) as solvent is described.     

Novel One-Pot Multicomponent Synthesis of Substituted 2,3-Dihydro-2-(6-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-3-yl)phthalazine-1,4-diones and Substituted 3-[3-(N′-Benzylidene-hydrazino)-7H-[1,2,4] triazolo[3,4-b][1,3,4]thiadiazin-6-yl]-4-hydroxy-6-methyl-pyran-2-ones

A one-pot procedure has been developed for the synthesis of substituted 2,3-dihydro-2-(6-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-7H-[1,2,4]triazolo[3,4-b] [1,3,4]thiadiazin-3-yl)phthalazine-1,4-diones by reaction of 3-(2-bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one, 4-amino-5-hydrazino-4H-[1,2,4]triazole-3-thiol, and phthalic anhydrides in acetic acid medium. Similarly, a one-pot, three-component synthetic procedure has been developed for substituted 3-[3-(N¹-benzylidene-hydrazino)-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-6-yl]-4-hydroxy-6-methyl-pyran-2-ones from 3-(2-bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one, 4-amino-5-hydrazino-4H-[1,2,4]triazole-3-thiol, and various aromatic aldehydes in absolute ethanol and a few drops of glacial acetic acid.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]     

Synthesis of Certain 3-Aminopyrazolo[5,4-b]pyridine and 3,4-Substituted Pyrido[2′,3′：3,4]pyrazolo[5,1-c][1,2,4]triazine Derivatives

2-Thioxo-1,2-dihydropyridine derivatives 2a, 2b were reacted with methyl iodide to give 2-methylthiopyridines 3a, 3b, which were reacted with hydrazine hydrate to produce 3-aminopyrazolo[5,4-b]pyridines 4a, 4b. Compounds 4a, 4b were diazotized to afford the corresponding diazonium salts 5a, 5b, which were reacted with some active methylene compounds 6a-6h to give the corresponding pyrido[2′,3′ ： 3,4]pyrazole[5,1-c][1,2,4]triazines 7-14.     

均三唑并噻二唑衍生物的微波合成

在无溶剂无催化剂微波辐射下,羧酸与1,3-二氨基硫脲快速反应高产率得到了3-取代基-4-氨基-5-巯基-1,2,4-三唑,该化合物与苯甲酰氯在无溶剂无催化剂微波促进下可以方便地制备化合物3-取代基-6-苯基-1,2,4-三唑[3,4-b][1,3,4]噻二唑。该方法具有反应时间短、环境友好、易于纯化及高产率的优点。产物结构经IR和1HNMR谱进行了表征。     

Novel [1,2,4]triazolo[3,4-b][1,3,4]thiadiazine and [1,2,4]triazolo[3,4-b][1,3,4]thiadiazepine Derivatives: Synthesis,Anti-Viral In Vitro Study and Target Validation Activity

This study of the interaction system of binucleophilic 3-substituted 4-amino-4H-1,2,4-triazole-5-thiols and 3-phenyl-2-propynal made it possible to develop a new approach to synthesis of such isomeric classes as 7-benzylidene-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazine and 8-phenyl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazepine. Among the 20 compounds studied in vitro against influenza A/Puerto Rico/8/34 (H1N1) virus, half of them demonstrated selectivity index (SI) of 10 or higher and one of them (4-((3-phenylprop-2-yn-1-yl)amino)-4H-1,2,4-triazole-3-thiol) possessed the highest (SI > 300). Docking results and values showed that the preferred interactant for our ligands was M2 proton channel of the influenza A virus. Protein-ligand interactions modeling showed that the aliphatic moiety of ligands could negatively regulate target activity level.     

Preparation and Spectral Characterization of 3-Benzyl-6-aryl-1,2,4-triazolo[3,4-b][1,3,4]thiadiazoles

3-Benzyl-4-amino-5-mercapto-1,2,4-triazole reacted with aromatic acids in the presence of phosphorus oxychloride, yielding a series of new compounds, i.e., 3-benzyl-6-aryl-1,2,4-triazolo[3,4-b][1,3,4]thiadiazoles, each of which has an active methylene at 3-position. The structures of all the title compounds were confirmed by elementary analysis, IR, 1H NMR and 13C NMR spectra.     

Synthesis and Crystal Structure of 3-Benzyl-6-trichloromethyl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazole

The title compound 3-benzyl-6-trichloromethyl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazole I （C11HTC13N4S, Mr = 333.62） has been synthesized, and its structure was determined by elemental analyses, IR, ^1H NMR, ^13C NMR, and X-ray diffractions. The crystal is of triclinic, space group P1^-, with a = 5.898（3）, b = 10.510（4）, c = 11.580（5） A, α = 74.936（7）, β= 75.476（7）, γ = 79.647（7）°, V= 665.9（5）/A^3, F（000） = 336, Z= 2, Dc = 1.664 g/cm^3, 2 = 0.71073A, p = 0.834 mm^-1, the final R = 0.0605 and wR = 0.0900. The secondary bonding interactions （SBIs） S…N and π-π stacking interactions are found in the crystal structure and they link the molecules into a three-dimensional network.     

5,6-2H-1,2,4-三唑[3,4-b][1,3,4]噻二嗪衍生物的合成及抗癌活性测定

取代苯甲醛与4-氨基-5-(3,4,5-三甲氧基苯基)-1,2,4-三唑-3-硫酮(2)缩合生成5-(3,4,5-三甲氧基苯基)-4-取代苯基亚胺基-1,2,4-三唑-3-硫酮(3),再烷基加成化为新型5,6-2H-1,2,4-三唑[3,4-b][1,3,4]噻二嗪衍生物4.化合物结构经1HNMR 13C NMR,IR以及元素分析确认.采用噻唑兰(MTT)比色法进行化合物抑制人体前列腺癌细胞(PC3)体外活性测试,结果表明所合成的化合物具有不同程度的抑制PC3活性,其中化合物4a在10μmol·L-1浓度下对PC3的抑制率为75.9%.     

Anodic formation of 3,6-diaryl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles and 2(3-aryl-5-methyl-1H-[1,2,4]triazol-1-yl)-5-aryl-1,3,4-thiadiazoles

3,6-Disubstituted 1,2,4-triazolo[3,4-b][1,3,4]thiadiazoles together with the unknown systems 2-(3-aryl-5-methyl-1H-[1,2,4]triazol-1-yl)-5-aryl-1,3,4-thiadiazoles were obtained by anodic oxidation, under aprotic conditions, of aryl aldehyde N-(5-aryl-1,3,4-thiadiazol-2-yl) hydrazones. Mechanistic proposals are given.     

Preparation and Electrochemical Properties of 3-Phenyl-6-aryl-1,2,4-triazolo[3,4-b][1,3,4]-thiadiazoles

Introduction Since Tang[1] firstly reported the electroluminescence of 8-hydroxyquinoline aluminium, much attention has been paid to the organic compound as electro-luminescent material. Especially, electron transport materials play an important role in organic light-emitting diode(OLED). 2-(4-Biphenyl)-5-(t-butylphenyl)-1,3,4-oxadiazole(PBD), as a kind of popular electron injection/transport materials, can improve remarkably the injection balance of electrons and holes. As a result, it can amend the properties of OLED[2,3].     

Preparation and Electrochemical Properties of 3-Phenyl-6-aryl-1,2,4-triazolo[3,4-b][1,3,4]-thiadiazoles

Since Tang firstly reported the electroluminescence of 8-hydroxyquinoline aluminium, much attention has been paid to the organic compound as electro-luminescent material. Especially, electron transport materials play an important role in organic light-emitting diode (OLED).2-(4-Biphenyl)-5-(t-butylphenyl)-1, 3,4-oxadiazole (PBD), as a kind of popular electron injection/transport materials, can improve remarkably the     

Synthesis of some substituted triazolo[4,3-b][1,2,4]triazines as potential anticancer agents

The synthesis of some 3-substituted amino-6,7-diphenyl-1,2,4-triazolo[4,3-b][1,2,4]triazines (15) by cyclodesulfurisation of the corresponding N-(5,6-diphenyl-1,2,4-triazin-3-yl)-N-[substituted thio (carbamoyl)]hydrazines (3) using dicyclohexylcarbodiimid (DCC) and mercuric chloride is described. Moreover, trials to prepare 3-substituted amino-7-hydroxy-6-methyl-1,2,4-triazolo[4,3-b][1,2,4]triazines were not successful.

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Synthese einiger substituierter Triazolo[4,3-b][1,2,4]-triazine als potentielle Antikrebswirkstoffe

Zusammenfassung Es wird die Synthese einiger 3-substituierter Amino-6,7-diphenyl-1,2,4-triazolo[4,3-b][1,2,4]-triazine (15) mittels Cyclodesulfurisierung der entsprechenden N-(5,6-Diphenyl-1,2,4-triazin-3-yl)-N-[subst.thio(carbamoyl)]-hydrazine (3) unter Verwendung von Dicyclohexylcarbodiimid (DDQ) beschrieben. Versuche zur Herstellung von 3-substituierten Amino-7-hydroxy-6-methyl-triazolo[4,3-b][1,2,4]-triazinen schlugen fehl.