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6-Methyl-N-(2-methylphenyl)-3-phenyl-1,6-dihydro-1,2,4,5-tetrazine-1-carboxamide  [cached]
Feng Xu,Weixiao Hu
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808020199
Abstract: In the title compound, C17H16N5O, the central tetrazine ring adopts an unsymmetrical boat conformation with the two C atoms as flagpoles. This compound can be considered as having homoaromaticity. The crystal structure is stabilized by intermolecular C—H...O interactions between a benzene H atom and the carbonyl O atom.
Grzegorz Dutkiewicz,Teresa Borowiak,Jarosław Spychała
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809008599
Abstract: Molecules of the title compound, C16H8N6, lie on crystallographic inversion centres. A dihedral angle of 16.1 (1)° is formed between the central tetrazine ring and the plane of each cyanophenyl group. The molecules form stacks along [100] with a perpendicular interplanar separation of 3.25 (1) . C—H...N interactions are formed between molecules in neighbouring stacks.
N1,N4,3,6-Tetramethyl-1,2,4,5-tetrazine-1,4-dicarboxamide  [cached]
Na-Bo Sun,Guo-Wu Rao,Qun Shen
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812022519
Abstract: The asymmetric unit of the title compound, C8H14N6O2, contains two independent molecules. In one molecule, the amide-substituted N atoms of the tetrazine ring deviate from the plane [maximum deviation = 0.028 (1) ] through the four other atoms in the ring by 0.350 (2) and 0.344 (2) , forming a boat conformation, and the mean planes of the two carboxamide groups form dihedral angles of 10.46 (13) and 20.41 (12)° with the four approximtely planar atoms in the tetrazine ring. In the other molecule, the amide-substituted N atoms of the tetrazine ring deviate from the plane [maximum deviation = 0.033 (1) ] through the four other atoms in the ring by 0.324 (2) and 0.307 (2) , forming a boat conformation, and the mean planes of the two carboxamide groups form dihedral angles of 14.66 (11) and 17.08 (10)° with the four approximately planar atoms of the tetrazine ring. In the crystal, N—H...O hydrogen bonds connect molecules to form a two-dimensional network parallel to (1-1-1). Intramolecular N—H...N hydrogen bonds are observed.
Synthesis and Antitumor Activity of 3-Methyl-4-oxo-3,4-dihydroimidazo [5,1-d][1,2,3,5]tetrazine-8-carboxylates and -carboxamides  [PDF]
Dan Liu,Jian-Guo Yang,Jie Cheng,Lin-Xiang Zhao
Molecules , 2010, DOI: 10.3390/molecules15129427
Abstract: Seventeen novel 3-methyl-4-oxo-3,4-dihydroimidazo[5,1-d][1,2,3,5]tetrazine-8-carboxylate and -carboxamide derivatives were synthesized and evaluated for their growth inhibition in seven human solid tumor and a human leukemia HL-60 cell lines. Compound IVa showed more activity than the other compounds and the positive control temozolomide. In the presence of 40 mg/mL of IVa, the survival rate of all tested tumor cells was less than 10%. Esters displayed more potent antitumour activity than amides and temozolomide against HL-60 cells. These compounds also exhibited considerably enhanced water-solubility.
K. Hemalatha*, Nandakishore Agarwal and G. Buchappa
International Journal of Pharmaceutical Sciences and Research , 2013,
Abstract: A novel N-(2-Chloro-6-methylphenyl)-2-[[6-[4-(2-hydroxyethyl)-1-pipear azinyl]-2-methyl-4-pyrimidinyl] amino]-5-thiazolecarboxamide derivatives (6a-6d) and (8a-8b) were synthesized by coupling 2-[(6-chloro-2-methylpyrimidin-4ylamino]-N-(2-chloro-6-methylphenyl) thiazole-5-Carboxamide(3) with Piperazine derivatives(4,7) in butanol and DIPEA (Diisopropylethylamine) at 120oC for 4-5hrs. All the synthesized compounds were characterized physically and elucidated by Infrared spectroscopy, Mass spectroscopy, 1H-NMR spectroscopic techniques. All the synthesized compounds were subjected to Molecular docking studies by using 2GQG as its PDB ID. Among all the compounds, 6a, 6b, 6d, 8c and 8b exhibit anticancer activity.
ApplicationofaKepleratetypegiantnanoporousisopolyoxomolybdateasareusablecatalystforthesynthesisof1,2,4,5-tetrasubstitutedimidazoles  [PDF]
Ahmad Nakhaei,Abolghasem Davoodnia
催化学报 , 2014, DOI: 10.1016/S1872-2067(14)60174-1
Abstract: ?TheKeplerate-typegiantnanoporousisopolyoxomolybdate(NH4)42[MoVI72MoV60O372-(CH3COO)30(H2O)72],denoted{Mo132},hasbeenusedasacatalystforthesynthesisof1,2,4,5-tetrasubstitutedimidazolesbytheone-pot,four-componentthermalreactionofbenzilwitharomaticaldehydes,primaryamines,andammoniumacetateundersolvent-freeconditions.Thecatalystwaspreparedaccordingtoapreviouslypublishedliteratureprocedureusinginexpensiveandreadilyavailablestartingmaterials,andsubsequentlycharacterizedbyFT-IR,UVandX-raydiffractionspectroscopy,aswellasmicroanalysis.Theresultsshowedthat{Mo132}exhibitedhighcatalyticactivitytowardsthesynthesisof1,2,4,5-tetrasubstitutedimidazoles,withthedesiredproductsbeingformedingoodtohighyields.Furthermore,thecatalystwasrecyclableandcouldbereusedatleastthreetimeswithoutanydiscerniblelossinitscatalyticactivity.Overall,thisnewcatalyticmethodforthesynthesisof1,2,4,5-tetrasubstitutedimidazolesprovidesrapidaccesstothedesiredcompoundsfollowingasimplework-upprocedure,andavoidstheuseofharmfulorganicsolvents.Thismethodthereforerepresentsasignificantimprovementoverthemethodscurrentlyavailableforthesynthesisoftetrasubstitutedimidazoles.
Processing of polysiloxane-derived porous ceramics: a review  [cached]
B V Manoj Kumar and Young-Wook Kim
Science and Technology of Advanced Materials , 2010,
Abstract: Corrigendum
Daniel Chartrand,Fran?ois Laverdière,Garry Hanan
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536807064057
Abstract: The title compound, C13H9N5, is the first asymmetric diaryl-1,2,4,5-tetrazine to be crystallographically characterized. We have been interested in this motif for incorporation into supramolecular assemblies based on coordination chemistry. The solid state structure shows a centrosymmetric molecule, forcing a positional disorder of the terminal phenyl and pyridyl rings. The molecule is completely planar, unusual for aromatic rings with N atoms in adjacent ortho positions. The stacking observed is very common in diaryltetrazines and is dominated by π stacking [centroid-to-centroid distance between the tetrazine ring and the aromatic ring of an adjacent molecule is 3.6 , perpendicular (centroid-to-plane) distance of about 3.3 ].
1-Benzoyl-3,6-diphenyl-1,4-dihydro-1,2,4,5-tetrazine  [cached]
Feng Xu,Zhen-Zhen Yang,Xiao-Fang Chen,Wen-Xiu Zheng
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810038067
Abstract: In the title compound, C21H16N4O, the central tetrazine ring adopts an unsymmetrical boat conformation with the two N atoms as the bow and stern. The crystal packing is stabilized by intermolecular N—H—O hydrogen bonds.
Desorption Kinetics of 1,2,4,5-Tetrachlorobenzene in Sediments

SHU Yue-hong,HUANG Xiao-ren,JIA Xiao-shan,

环境科学 , 2009,
Abstract: Sediment desorption batch technique experiments were conducted to study the influence of different types of natural organic matter(NOM) of sediment,initial solid-phase solute loading levels and temperatures on the desorption rates of 1,2,4,5-tetrachlorobenzene.A(4-parameter) biphasic first-order kinetic model described the desorption of 1,2,4,5-tetrachlorobenzene from the sediments. The results indicate that the rate constants k_s for the slowly desorbing fraction of each sample is up to 2 orders of magnitu...
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