Syntheses and properties of new herbicidal 2-arylthio-1 ,2,4-triazolo[1,5-a] pyrimidine derivatives

In search of novel herbicides with high activity, a series of 2-arylthio-1,2,4- triazolo [1, 5-a ] pyrimidines (3) were synthesized by cyclization of 5-amino-3-arylthio-1,2,4-triazoles with 1,3-diketones or by the nucleophilic substitution of substituted thiophenols with 2-methylsulfonyl-1, 2, 4-triazolo [ 1, 5-a]-pyrimidine. The structures of all compounds prepared were confirmed by 1H NMR and MS spectroscopy along with elemental analyses. Preliminary bioassays indicated that some of the compounds 3 had good herbicidal activity against rape. In addition, the regioselectivity in the reaction of 5-amino-3-sub-stituted arylthio-1,2,4-triazoles with benzoylacetone was studied.     

Synthesis,characterization and biological studies of cobalt(II) and nickel(II) complexes with new Schiff bases

Complexes of CoII and NiII with new Schiff bases derived from 4-amino-5-sulfanyl-1,2,4-triazoles and glyoxal, biacetyl or benzil have been prepared. All have the stoichiometry ML(H2O)2, with L coordination via the two imine nitrogens and two thiolato sulfurs in an overall octahedral geometry.Some of the complexes were screened for their antibacterial and antifungal activity, and one representative CoII complex was evaluated for oxytocic activity.     

Spectral,Antimicrobial, and Thermal Studies of Some Transition Metal Complexes Derived from Bidentate Ligands Containing N and S Donor Atoms

Abstract

Bidentate ligands have been synthesized by the reaction of 2,4-dichlorobenzaldehyde with 4-amino-5-mercapto-1,2,4-triazole and 4-amino-5-mercapto-3-propyl-1,2,4-triazole. The ligands react with acetates of Co(II), Ni(II), Cu(II), and Zn(II) to yield 1:2 [metal:ligand] complexes. The newly synthesized compounds were characterized by elemental analyses, spectral (UV-Vis, IR, ¹H NMR, fluorescence, ESR) studies, thermal techniques, and magnetic measurements. Thermal studies of the complexes showed a multistep decomposition pattern. A square planar geometry for Cu(II) and octahedral geometry for Co(II), Ni(II), and Zn(II) complexes have been proposed. The synthesized complexes exhibit enhanced antimicrobial activity against Staphylococcus aureus, Bacillus subtilis, Aspergillus niger, and A. flavus compared to parent ligands. However, tested compounds did not exhibit any activity against Escherichia coli and Pseudomonas aeruginosa.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

Synthesis of new pyrazoles,oxadiazoles, triazoles,pyrrolotriazines, and pyrrolotriazepines as potential cytotoxic agents

4-Oxo-4-phenylbutanehydrazide (1) reacted with many active methylene reagents such as acetylacetone, diethylmalonate, ethylacetoacetate, ethylcyanoacetate, benzoyl-acetonitrile, and malononitrile under neat conditions to afford the corresponding pyrazoles (2–7) , also, treatment of butanehydrazide (1) with electrophilic reagents as triethylorthoformate, dimethylformamide-dimethylacetal, acetic anhydride, and carbon disulfide to give 1,3,4-oxadiazoles (8,10,11) and N′-acetyl-butanehydrazide (9) . Reacted of butanehydrazide (1) with potassium thiocyanate gave 1,2,4-triazoles (12) . Similarly, treatment of (1) with chloroacetamide gave 1,2,4-triazinones (13) . The pyrrolotriazinones (14) was obtained by cyclization of (13) . Also, butanehydrazide ( 1 ) was utilized as a starting material for the synthesized of new Schiff bases as N′-(4-sub-benzylidene)-phenylbutane-hydrazide (15a-c) , which are used as an initiative to prepare new compounds such as 1,2,4-triazepinones (16a-c) , pyrrolotriazepinones (17a-c) , 1,2,4-triazines (18a-c) , and pyrrolotriazines (19a-c) by reacted of (15a-c) with each chloroacetamide or formamide. The chemical structure of the newly prepared compounds was determined through the spectrum data, including IR, NMR, and MS. The prepared compounds were tested for their in vitro antitumor activities. The compounds 17a-c , 16a-c , and 19a-c displayed activity against several types of cancer cell lines.     

Synthesis and properties of mixed-substituted nickel triazolephthalocyaninates

Homo- and mixed-substituted nickel triazolephthalocyaninates were synthesized by the reactions of nickel complexes of substituted 3,5-bis(3-iminoisoindolin-1-ylideneamino)-1,2,4-triazoles with 4-phenoxyphthalonitrile and 4-phenylthiophthalonitrile. The structures of these compounds were established by UV-Vis and IR spectroscopy, mass spectrometry, and elemental analysis, and their physicochemical properties were studied.     

Structural modification studies of 3-piperonylsydnone I. synthesis of piperonyl-substituted pyrazoles,isoxazoles, triazoles,oxadiazoles and thiadiazoles

As a structural modification study of the antimalarial compound 3-piperonylsydnone, a number of pyrazoles, isoxazoles, 1,2,4-triazoles, ψ-1,2,4-triazoles, 1,3,4-oxadiazoles, 1,3,4-thiadiazoles and their intermediates all of which contain the piperonyl moiety have been synthesized. The antimalarial activity of these compounds was found to be less than that of the original sydnone. With the exception of 2,4-diamino-5-piperonylpyrimidine, among the compounds tested, those which showed survival time of eleven days or over all possess a N-N linkage.     

Binuclear transition metal complexes of bicompartmental SNO donor ligands: synthesis,characterization, and electrochemistry

A series of new binucleating Co^II, Ni^II, Cu^II, and Zn^II complexes of bicompartmental ligands with SNO donors was prepared. The Schiff bases were obtained by the condensation of 4,6-diacetylresorcinol and mercapto-substituted 1,2,4-triazoles. The ligands and their complexes were characterized by elemental analysis, infrared, ¹H-NMR, UV-Vis, FAB-mass, and ESR spectral studies, magnetic susceptibility, and conductivity measurements. All the complexes were monomeric and binuclear. Ni^II and Co^II complexes were octahedral, whereas Cu^II and Zn^II complexes were square planar and tetrahedral, respectively. The compounds are investigated for electrochemical activity.     

Efficient in Situ Synthesis of 3,5-Disubstituted-1,2,4-triazoles Under Microwave-Assisted Conditions

Based on an efficient in situ metal/ligand reaction, a serial of 3,5-disubstituted-1,2,4-triazoles were synthesized via cycloaddition of organonitriles and ammonia under microwave conditions. This synthetic protocol provides a concise and high-yield access to 3,5-disubstituted-1,2,4-triazoles in organic synthesis. Moreover, the tautomerism of the product was also investigated.

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

Synthesis of 3,5-disubstituted 1,2,4-triazoles containing an amino group

3,5-Disubstituted 1,2,4-triazoles containing linear and cyclic amine fragments have been synthesized by thermal cyclization of N′-(1-iminoalkyl) hydrazides prepared by condensation of imido esters with carboxylic acid hydrazides. The initial imido esters have been synthesized by the Pinner reaction, as well as by reaction of nitriles with methanol in the presence of a catalytic amount of sodium methoxide. A procedure has been developed for the synthesis of 5-substituted 3-(3-nitrophenyl)-1,2,4-triazoles which have been converted to 3-aminophenyl derivatives by reduction with hydrazine hydrate over Raney nickel.     

New Bis-4H-1,2,4-triazoles and Their In Vitro Study as DNA Methylation Inhibitors

Russian Journal of General Chemistry - Bis-1,2,4-triazoles with aryl and alkyl linkers were synthesized. In order to increase their hydrophilicity and potential biological activity, pharmacophore...     

含1,2,4-三唑基二硫代磷酸酯新化合物合成与生物活性研究

合成了12个含1,2,4-三唑的二硫代磷酸酯新化合物。经元素分析,IR,1^HNMR确定了新化合物结构。结果表明,化合物对蚜虫等有较强生物活性,讨论了该类化合物合成方法及生物活性。     

Synthese de 5-Aryl-3-[(1-dialcoxyphosphonyl)methyl]-1,2,4-triazoles a Partir d'Imidates N-Chloroacyles

A variety of 5-aryl-3-[(1-dialcoxyphosphonyl)methyl]-1,2,4-triazoles 3 has been synthesized efficiently by treatment of trialkylphosphites with 5-aryl-3-chlorométhyl-1,2,4-triazoles 2 . Compound 2 has been prepared by action of N-chloroacylimidates 1 with hydrazines. The structure of triazoles 2 and 3 have been unequivocally confirmed by means of IR, 1 H, 13 C, 31 P NMR spectroscopy and mass spectra.     

Heterocyclic nitro compounds

A number of triazolylpropanones were synthesized by oxidation of 1-(2-hydroxypropyl)-3-nitro-5-R-1,2,4-triazoles obtained by condensation of 3-nitro-5-R-1,2,4-triazoles with propylene oxide. Similar triazolylbutanones were obtained by reaction of 3-nitro-5-R-1,2,4-triazoles with methyl vinyl ketone.See [1] for communication XIX.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 991–994, July, 1976.     

Lanthanum(III) and praseodymium(III) complexes of acetylferrocenyl mercaptotriazoles

Schiff base complexes derived from 3-substituted phenyl-4-amino-thiolato-1,2,4-triazoles and acetylferrocene (LH), with lanthanum(III) and praseodymium(III) of the type [M(L)₃] have been prepared and characterised by elemental analysis, electrical conductance, magnetic moments and spectral (electronic, i.r., ¹H-n.m.r. and ¹³C-n.m.r.) data. The thermal behaviour of selected complexes was investigated by t.g. and d.t.g. techniques.     

Synthesis of novel fluorinated benzothiazol-2-yl-1,2,4-triazoles: Molecular docking,antifungal evaluation and in silico evaluation for SAR

Lead hybridization concept was used to design and synthesize twenty novel hybrid compounds by combining fungicidal leads viz. 6-flouro-1,3-benzothiazol-2-amine and 1,2,4-triazoles in a single molecule, with the aim of discovery of high potential novel fungicides. Antifungal evaluation of synthesized 6-flourobenzothiazol-2-yl-1,2,4-triazoles against various phytopathogenic fungi revealed synergistic effect of combination of leads with one another in all the test compounds. Some of the synthesized compounds showed excellent fungitoxicity comparable with the standard fungicides used. In silico toxicity of all the compounds was equivalent to the standard fungicides used. Docking studies and Lipinski filtration were performed in order to present the rationale of structure activity relation. Compounds 2, 8, 15 and 18 were screened to act as leads for further modification and use.     

Preparation of silicon-containing polymers IV. Thermally stable organosilicon poly-1,2,4-triazoles

Novel silicon-containing poly-1,2,4-triazoles have been synthesized by the reaction of polyhydrazide precursors and aniline in polyphosphoric acid (PPA) at 260°C. The polyhydrazide intermediates were prepared from aromatic dihydrazides and silicon-containing acid dichlorides via interfacial polycondensation. These polymers and their intermediates were characterized by infrared spectroscopy (IR), solubility, and by solution viscosity. The thermal behavior of these polytriazoles has been studied by dynamic thermogravimetry.     

Syntheses of 1-substituted 1,2,4-triazoles,imidazoles and benzimidazoles

Substituted 2-phenethyl-1,2,4-triazoles, 1-phenethylimidazoles 3 and 1-phenethylbenzimidazoles 5 were synthesized from the reaction of compound 8 with tri-n-butyltin hydride in good yield. The reaction of substituted-2-phenethyl halide with 1H-1,2,4-triazoles, imidazoles and benzimidazoles gave a low yield. The yield was increased by the use of substituted-2-phenethyl p-toluensulfonate.     

Ring chain transformations. XIV. 3-(ω-Aminoalkyl)-1,2,4-triazoles by reaction of isothiosemicarbazides with lactam acetals or lactim ethers

Isothiosemicarbazide hydrohalides 1 react with lactam acetals 2 or lactim ethers 3 by the formation of lactamisothiosemicarbazones 4 or ring transformed 3-(ω-aminoalkyl)-1,2,4-triazoles 6 . The latter can independently by synthesized by alkylation of lactamthiosemicarbazones 9 . Condensation of primary 3-(ω-aminoalkyl)-1,2,4-triazoles 6 with lactim ethers 7 can lead to 3-lactamiminoalkyl-1,2,4-triazoles 8 .     

A study on ester formylhydrazones

A series of ester formylhydrazones 2 were synthesized from the reaction of alkyl imidate hydrochlorides 1 with formylhydrazine. Treatment of 2 with hydrazine hydrate, ethyl carbazate and tert-butyl carbazate led to the formation of 3-alkyl-4-amino-, 3-alkyl-4-ethoxycarbonylamino- and 3-alkyl-4-tert-butoxycar-bonylamino-4H-1,2,4-triazoles 3–5 , respectively. Reaction of compounds 2 with formylhydrazine gave N,N'-diformylhydrazine 6 . Compounds 2 were reacted with 2,5-dimethoxytetrahydrofuran to afford 3-alkyl-4-(1H-pyrrol-1-yl)-4H-1,2,4-triazoles 8 .     

Studies on Pyrazine Derivatives. 38. Synthesis, Reactions, and Tuberculostatic Activity of Pyrazinyl-substituted Derivatives of Hydrazinocarbodithioic Acid

The synthesis of N'-[amino(6-chloro- and 6-cycloaminopyrazin-2-yl)methylene]carbodithioic acid mono- and diesters and their reactions are described. Cyclization of monoesters with secondary amines in acidic media gave the 1,3,4-thiadiazole derivatives, while the cyclization of diesters with amines yielded 1,2,4-triazoles with the amine substituent in position 3. The in vitro tuberculostatic activity of the prepared compounds was tested.