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Within this study, 20 2-[(5,6-diaryl-1,2,4-triazin-3-yl)thio]-N-(benzo/thiazol-2-yl)acetamide derivatives (4a-4t) were synthesized and COX inhibitory activities of the compounds were investigated. Compounds 4k-4o, which have a 4-methoxyphenyl group within their structures, showed strong inhibitory activity on COX-2 enzyme, even compound 4k, namely 2-{[5,6-bis(4-methoxyphenyl)-1,2,4-triazin-3-yl]thio}-N-(thiazol-2-yl)acetamide exhibited higher selectivity on this enzyme (IC50:3.06 µM). Molecular docking studies were performed for compound 4k on COX-1 and COX-2 enzymes and the results were found to support the molecule's COX-2 selectivity. [ABSTRACT FROM AUTHOR]

1,2,4-Triazine derivatives showed a significant role in the biological and pharmacological fields, which motivated us to study the biological and cytotoxicity activity of its first-row transition metal complexes. Three new complexes of Co(II), 1; Ni(II), 2; and Cu(II), 3 with 3-(2-benzylidenehydrazinyl)-5-(4-isobutylphenyl)-1,2,4-triazine, L were synthesized and characterized by standard physicochemical and theoretical methods. The structure of these complexes was evidenced by IR and 1H NMR spectroscopies, elemental analysis, magnetic measurements, molar conductance, mass spectrometry, and DFT modeling. The ligand behaved as a bidentate chelator that coordinates by triazine nitrogen-2 and azomethine nitrogen in a 2:1 (ligand : metal) ratio. The anticancer activity of the compounds was investigated against breast cancer cells (Mcf7 cell line). The antimicrobial activities of the ligand and its complexes were evaluated against different types of bacteria. Cu(II) was the most efficacious antimicrobial, with greater inhibition zones than the other complexes. The molecular docking studies were implemented to consider the binding attraction of the compounds with the receptors of breast cancer oxidoreductase (PDB:3HB5) and those of the COVID-19 main protease viral protein (PDB ID: 6LU7). The DFT calculations were used to confirm the molecular geometry of the new complexes. [ABSTRACT FROM AUTHOR]

Fragmentation of the Ge–Ph bond in 2-(6-tBu-5-triphenylgermyl-2-R-4,5-dihydro-1,2,4-triazin-3(2H)-ylidene)malononitriles (R = Me, nBu) using lithium naphthalenide and further electrophile trapping with H+, Ph3SiCl or Ph3GeBr furnished the corresponding 5-Ph2HGe–, Ph3Si–Ph2Ge– or Ph3Ge–Ph2Ge– derivatives. In the case of R = CH2CO2tBu, metalation at the exocyclic methylene group was observed to give tert-butyl 7-amino-3-tBu-8-cyanopyrrolo[1,2-b][1,2,4]triazine-6-carboxylate as a result of cyclization/Ge atom elimination. Structures of the synthesized compounds were confirmed by spectral and XRD data. [ABSTRACT FROM AUTHOR]

Reactions of 3-tert-butyl-8-methylpyrazolo[5,1-c][1,2,4]triazine with lithium phenyldimethylsilanide and triphenylsilanide in THF media at −85 to −60 °C led to the formation of the silicon C(4)-addition products in high yields. Aromatic 3-tert-butyl-8-methyl-4-(triphenylsilyl)pyrazolo[5,1-c][1,2,4]triazine has been synthesized by oxidation of the corresponding 1,4-dihydro derivative using NBS/Et3N in pentane at −30 to −15 °C. Preferential N(1)-nucleophilic additions of silanides were observed for the sterically hindered 3,4-di-R-8-methylpyrazolo[5,1-c][1,2,4]triazines (R = t-Bu, Ph3Si). Novel C–Si derivatives of 1,2,4-triazines, as well as some other isolated compounds were characterized by IR, 1H, 13C, 29Si NMR, HRMS data and X-ray crystallography. [ABSTRACT FROM AUTHOR]

A set of 1,2,4-triazine derivatives were designed as cyclooxygenase-2 (COX-2) inhibitors. These compounds were synthesized and screened for inhibition of cyclooxygenases (COX-1 and COX-2) based on a cellular assay using human whole blood (HWB) and lipoxygenase (LOX-15) that are key enzymes in inflammation. The results showed that 3-(2-(benzo[d][1,3]dioxol-5-ylmethylene)hydrazinyl)-5,6-bis(4-methoxyphenyl)-1,2,4-triazine (G11) was identified as the most potent COX-2 inhibitor (78%) relative to COX-1 (50%). Ferric reducing anti-oxidant power (FRAP) assay revealed that compound G10 possesses the highest anti-oxidant activity. The compound G3 with IC50value of 124 μM was the most potent compound in LOX inhibitory assay. Molecular docking was performed and a good agreement was observed between computational and experimental results. [ABSTRACT FROM PUBLISHER]

Two Cd(II) complexes, [Cd(PDT)2Cl2]·H2O (1) and [Cd(PDT)2Br2][image omitted]H2O (2) (PDT is the abbreviation of 3-(2-Pyridyl)-5,6-diphenyl-1,2,4-triazine), have been synthesized and characterized by elemental analysis IR, 1H NMR spectroscopy, and studied by thermal analysis as well as X-ray crystallography. The supramolecular associations with these complexes have also been analyzed. In both cases, the cadmium(II) ion is in a slightly distorted octahedral environment. The two complexes are extended into networks (2D in 1 and 3D in 2) through hydrogen bonds and weak directional intermolecular interactions. [ABSTRACT FROM AUTHOR]

Pb(II) and Cd(II) complexes, {[Pb2(PDTS)2(CH3OH)((H2O)2] ⋅ H2O}n (1) and [Cd(PDTS)(H2O)4] ⋅ 2H2O (2) (PDTS2- = 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine-p,p'-disulfonate), are synthesized and characterized by elemental analysis, infrared (IR), 1H-NMR spectroscopy, and thermal analysis. The single-crystal structure of 1 shows that the complex forms a 2-D polymeric network containing two types of Pb2+ with coordination number eight (PbN2O6). Both possess hemidirected coordination geometries. The single-crystal structure of 2 shows distorted octahedral geometry for cadmium(II), CdN2O4. These compounds are the first complexes of “PDTS2-”. The supramolecular features in these complexes are guided/controlled by hydrogen bonding and noncovalent intermolecular interactions. [ABSTRACT FROM AUTHOR]

Two new Pb(II) complexes, [Pb(TPT)(NO3)2]n (1) and [Pb(TPT)2(ClO4)(H2O)] · ClO4 · H2O (2) (TPT is the abbreviation of 3,5,6-tris(2-pyridyl)-1,2,4-triazine), have been synthesized and characterized by single-crystal X-ray diffraction. Lead(II) in the compounds of 1 and 2 is nine coordinate (rare mode), PbN3O6 and PbN6O3, respectively. Both have hemidirected coordination geometries. The supramolecular features in these complexes are guided/controlled by hydrogen bonding and weak directional intermolecular C-H ··· O and π ··· π interactions. The thermal stabilities of 1 and 2 were investigated by thermogravimetric measurements. [ABSTRACT FROM AUTHOR]

Reaction of bis(hexafluoroacetylacetonato)copper(II) hydrate with 1,2,4-triazine (tz) in dichloromethane yields pentakis[bis(hexafluoroacetylacetonato)triazinecopper(II)] [Cu(hfac)2(tz)]5 (hfac = hexafluoroacetylacetonate) (1). The complex crystallizes in the triclinic space group P-1, with cell parameters a = 11.4124(5), b = 13.3405(5), c = 16.1794(7) Å, α = 93.360(2)°, β = 108.700(2)°, γ = 100.293(2)° at 120(1) K. In the complex, the copper(II) ions show three types of coordination polyhedra: square planar, square pyramidal, and octahedral (4 + 2). The tz ligand also shows different coordination modes (bridging and monodentate). In addition, disorder is observed in the triazine molecule, either through non-crystallographic two-fold rotation about the longitudinal N,N-axis, or with respect to a crystallographic center of symmetry. The crystal structure of 1 consists of alternating trimers and dimers. The weak coordination of the tz molecules results in negligible magnetic exchange through the ring. [ABSTRACT FROM AUTHOR]

Novel N1-(phosphoryl moiety)-N2-(1,2,4-triazin-3-yl)hydrazines 4, 6, 8, 9 and 12, iminophosphorane 3, iminophosphane 5, 1,2,4-triazinyldiazaphospholine 7, 1,2,4,3-triazaphospholinotriazines 2, 10, 11, and 1,2,4-triazino[3,2-c][1,2,4,5] triazaphosphine 13 have been obtained via treatment 5,6-bis(4-bromophenyl)-3-hydrazino-1,2,4-triazine (1) with various polyfunctional phosphorus reagents by stirring at room temperature or refluxing for long time in tetrahydrofuran. Structures of these compounds have been deduced upon the basis of elemental and spectral data. Molluscicidal activity of the prepared compounds against Biomphalaria Alexandrina snails (the intermediate host of Schistosoma mansoni) showed considerable activities. [ABSTRACT FROM AUTHOR]

Novel 1,2,4-triazine, pyridine, and benzopyran derivatives have been synthesized from N-(2-benzothiazolyl)cyanoacetamide via its reaction with some electrophiles. The structure of the synthesized compounds was established by analytical and spectral data. [ABSTRACT FROM AUTHOR]

The reaction of 4-amino-6-methyl-5-oxo-3-thioxo-2H-1,2,4-triazine, (AMTTO, [1]), and 4-amino-5-methyl-3-thioxo-2H-1,2,4-triazole, (AMTT, [2]), with various aldehydes under classical heating and microwave irradiation in a solvent-free system resulted in the formation of the corresponding imines 3a–e and 4a–d. The compounds were characterized by their spectroscopic data and elemental analysis. Compound 3a was also characterized by X-ray diffraction studies. Crystal data for 3a at -80°C: triclinic, space group P-1, a = 796.7(2), b = 844.8(2), c = 1073.1(2) pm, α = 88.44(2)°, β = 76.59(2)°, γ = 63.42(2)°, Z = 2. [ABSTRACT FROM AUTHOR]

Some of novel N , N ′-bis-(1,2,4-triazin-4-yl)dicarboxylic acid amides ( 2-5 ) and thiadiazolo[2,3- b ][1,2,4]triazin-7-yl carboxylic acid derivatives ( 6 , 7 ) were prepared by heating 4-amino-6-methyl-5-oxo-3-thioxo-2,3,4,5-tetrahydro-1,2,4-triazine ( 1 ) with different dicarboxylic acids (oxalic, malonic, fumaric, maleic, succinic, and phthalic acids respectively) in POCl 3 . Refluxing 1 with 1-chloro-2,4-dinitrobenzene in DMF yielded 3-methyl-6-nitro-10 H -benzo[1,2,4]thiadiazino[2,3- c ][1,2,4]triazin-4-one ( 8 ). Condensation of 1 with 2,4-pentandione in refluxing acetic acid furnished 6-methyl-4-(1-methyl-3-oxobut-1-enylamino)-3-thioxo-3,4-dihydro-2 H -[1,2,4]triazin-5-one ( 9 ). 3,8-D imethyl[1,2,4] triazino[3,4- b ][1,3,4]thiadiazine-4,7-dione ( 11 ) was prepared by refluxing 1 with 2-bromopropionyl bromide in anhydrous benzene to afford the corresponding N -acetylated derivative 10 , which was cyclized by using triethylamine. Also, some triazinylquinazolinones 13a , b were obtained by fusion of 1 with 6-bromo(and/or 6,8-dibromo)-2-methyl-3,1-benzoxazin-4 H -ones. [ABSTRACT FROM AUTHOR]