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The reaction between 2‐hydroxy‐1‐naphthaldehyde and 3‐hydrazino‐5,6‐diphenyl‐1,2,4‐triazine produced a novel hydrazone ligand (DTHMN), which reacted with Cu(II) and Zn(II) metal ion in molar ratio 1:1, giving octahedral Cu(II)‐DTHMN and tetrahedral Zn(II)‐DTHMN nanosized complexes. The structural geometries have been elucidated on the basis of elemental analysis, nuclear magnetic resonance, infrared, electronic, and electron spin resonance spectra, and magnetic and molar conductance measurements as well as x‐ray diffraction and thermal analysis. TEM analysis showed that Zn(II)‐DTHMN complex has nano‐rode morphology shape. On the other hand, Cu(II)‐DTHMN has sphere shape within nanodomain. The DTHMN ligand exhibits ONN chelating sites through N‐triazine ring, azomethine nitrogen, and deprotonated OH group, forming the mononuclear metal complexes. The synthesized compounds showed a distinct solvatochromic behavior in different polar solvents. A bathochromic alteration is observed when moving from less to high polar solvents, indicating strong solute–solvent interactions accompanied by intramolecular charge transfer (ICT). The ground and excited state dipole moments of these compounds were determined experimentally by solvatochromic shift method using Bilot–Kawski, Lippert–Mataga, Bakhshiev, and Kawski–Chamma–Viallet functions and a microscopic Reichardt's solvent polarity parameter (ETN). The dipole moment is increased significantly upon excitation referring to stabilizing the excited species includes n–π* transition by polarity of solvent. The experimental results are generally consistent with those values obtained by B3LYP/GENECP method at 6‐311G(d,p) basis set for C, H, N, and O atoms and SDD (Stuttgart/Dresden) basis set for the metal atoms. The compounds were tested for antimicrobial efficiency against Gram‐positive bacteria, Gram‐negative bacteria, and fungus strain. Finally, molecular docking was used to study the interactions between donors (the current compounds) and receptors FabH–CoA complex (PDB code: 1HNJ). [ABSTRACT FROM AUTHOR]

Herein we report the first microwave‐assisted one‐pot three‐step metal‐free [4+2] procedure for the synthesis of 5,6‐substituted‐3‐hydrazinyl‐1,2,4‐triazines directly from commercially available aromatic and heteroaromatic ketones. The 3‐hydrazinyl‐1,2,4‐triazine can be isolated or further elaborated, after a simple work‐up, by direct condensation with different aldehydes or ketones to provide highly functionalized hydrazone‐derivatives. This protocol represents a rapid, efficient, and sustainable approach for the development of new highly functionalized 1,2,4‐triazine derivatives with potential biological interest. [ABSTRACT FROM AUTHOR]

A 1,2,4‐triazine based azidoxime was formed via the substitution of a chloroxime (3) with sodium azide in ethanol. This compound was characterized via single‐crystal X‐ray diffraction. This material has a calculated density of 1.746 g ⋅ cm−3 and is less sensitive to impact, spark, and friction, as compared to PETN and RDX. The dehydrated material has a calculated density of 1.823 g ⋅ cm−3 and the detonation pressure and velocity of 4 are calculated to be 29.1 GPa and 8.67 km ⋅ s−1, respectively. [ABSTRACT FROM AUTHOR]

Some new 1:1 (ML) and 1:2 (ML2) metal complexes of Co(II), Ni(II), Cu(II), and Zn(II) have been synthesized with novel ligand, that is, 4‐(3‐methylthiophene‐2‐ylmethyleneamino)‐3‐mercapto‐6‐methyl‐5‐oxo‐1,2,4‐triazine. Ligand and its metal complexes were characterized on the basis of various physicochemical techniques like elemental analysis, magnetic moment, molar conductance, cyclic voltammetry, and spectroscopic (1H‐NMR, infrared [IR], electronic, fluorescence, and electron spin resonance [ESR]) data. On the basis of these studies, octahedral and square planar geometries have been proposed for Co(II), Ni(II), Zn(II), and Cu(II) metal complexes, respectively. Thermogravimetric analysis (TGA) was carried out to study the thermal decomposition and stability of metal complexes. Electrochemical behavior of Cu(II) complexes have also been explored by cyclic voltammetry. The complexes have shown promising antimicrobial activity when checked by in vitro method against some bacterial and fungal strains. In addition to these studies, quantum mechanical approach was also performed in order to find some structural information of newly synthesized compounds. [ABSTRACT FROM AUTHOR]

This article describes a convenient method for the synthesis of 5‐aryl‐6‐methyl‐2,2′‐bipyridines through the direct introduction of a methyl group at the C5‐position of 1,2,4‐triazine moieties. At first 1,2,4‐triazine precursors are synthesized for this purpose. The reaction proceeds through SNH/SNips° substitution and subsequent aza‐Diels‐Alder reaction. In addition, mono‐ and dibromomethyl‐substituted 2,2'‐bipyridines are also synthesized to confirm the applicability of the present method. [ABSTRACT FROM AUTHOR]

The reaction of 3-amino-5-nitro-1,2,4-triazole with nitrous acid produces the corresponding diazonium salt. When the diazonium salt is treated with nitroacetonitrile, a subsequent condensation and cyclization reaction occurres to produced 4-amino-3,7-dinitrotriazolo-[5,1- c][1,2,4] triazine (DPX-26). X-ray crystallographic analysis shows that the DPX-26 has a density of 1.86 g cm−3, while it is calculated to have a heat of formation of 398.3 kJ mol−1. DPX-26 is predicted to approach the explosive performance of RDX but displays significantly better safety properties. Oxidation of DPX-26 using hypofluorous acid produces 4-amino-3,7-dinitrotriazolo-[5,1- c][1,2,4] triazine 4-oxide (DPX-27), which is also predicted to be a high-performance material with enhanced safety properties. [ABSTRACT FROM AUTHOR]

The development of materials for efficient chemoselective extraction of minor actinides remains at the forefront of research efforts in the area of separation science. Lewis basic complexants derived from nitrogen-donor scaffolds are often employed in this area due to favorable with the transuranic element americium. In the present work an efficient procedure for the preparation of eight useful 3-pyridin-2-yl-1,2,4-triazines (2 novel) is demonstrated via telescoped condensation with the requisite 1,2-dicarbonyl in two-pots without additives, differentially extractive work-up procedures, or recrystallization. Additional efforts in this area have demonstrated the utility of polar aprotic solvents for the preparation of nine functionalized pyridinyl-2,6- bis-1,2,4-triazines (4 novel) directly from the requisite 2,6-pyridine dicarbonitrile in 49-99% yield over four total steps. The streamlined preparation of these important materials and detailed synthetic procedures is reported herein. [ABSTRACT FROM AUTHOR]