6‐Aza‐2′‐deoxy­uridine and N3‐anisoyl‐6‐aza‐2′‐deoxy­uridine

In 2‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐1,2,4‐triazine‐3,5(2H,4H)‐dione (6‐aza‐2′‐deoxy­uridine), C₈H₁₁N₃O₅, (I), the conformation of the glycosylic bond is between anti and high‐anti [χ = −94.0 (3)°], whereas the derivative 2‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐N⁴‐(2‐methoxy­benzoyl)‐1,2,4‐triazine‐3,5(2H,4H)‐dione (N³‐anisoyl‐6‐aza‐2′‐deoxy­uridine), C₁₆H₁₇N₃O₇, (II), displays a high‐anti conformation [χ = −86.4 (3)°]. The furanosyl moiety in (I) adopts the S‐type sugar pucker (²T₃), with P = 188.1 (2)° and τ_m = 40.3 (2)°, while the sugar pucker in (II) is N (³T₄), with P = 36.1 (3)° and τ_m = 33.5 (2)°. The crystal structures of (I) and (II) are stabilized by inter­molecular N—H⋯O and O—H⋯O inter­actions.     

A Coordination Polymer from HAMTTO with Silver(I) (HAMTTO = 4‐Amino‐6‐methyl‐1,2,4‐triazine‐3‐thione‐5‐one)

The reaction of 4‐amino‐6‐methyl‐1,2,4‐triazine‐3‐thione‐5‐one, HAMTTO, with silver (I) nitrate in methanol led under deprotonation to the polymeric compound [(AMTTO)Ag]_n. The coordination polymer {[Ag(HAMTTO)]ClO₄}_n ( 1 ) is synthesized from the reaction of the latter polymeric compound with perchloric acid. Both compounds were characterized by elemental analysis and IR spectroscopy. Single‐crystal X‐ray diffraction studies on compound 1 showed that HAMTTO acts as a bidentate ligand and chelates the silver atom via its hydrazine nitrogen atom and its sulfur atom. Crystal data for 1 at ?90 °C: space group P2₁, Z = 2, a = 629.3(1), b = 748.7(1), c = 1071.7(1) pm, β = 98.28(1)°, R₁ = 0.0533.     

6‐Aza‐2′‐deoxy‐2′‐arabino­fluoro­uridine,a 2′‐deoxy­ribonucleoside with an N‐sugar conformation in the solid state and in solution

In the title compound, 2‐(2‐deoxy‐2‐fluoro‐β‐d ‐arabino­fur­anosyl)‐1,2,4‐triazine‐3,5(2H,4H)‐dione, C₈H₁₀FN₃O₅, the torsion angle of the N‐gly­cosylic bond is anti [χ = −125.37 (13)°]. The furan­ose moiety adopts the N‐type sugar pucker (³T₂), with P = 359.2° and τ_m = 31.4°. The conformation around the C4′—C5′ bond is antiperiplanar (trans), with a torsion angle γ of 177.00 (11)°. A network is formed via hydrogen bonds from the nucleobases to the sugar residues, as well as through hydrogen bonds between the sugar moieties.     

3,5‐Di­amino‐6‐(2‐fluoro­phenyl)‐1,2,4‐triazine–di­methyl­form­amide (1/1)

The title compound, C₉H₈FN₅·C₃H₇NO, contains two independent complexes in the asymmetric unit, each consisting of one 3,5‐di­amino‐6‐(2‐fluoro­phenyl)‐1,2,4‐triazine mol­ecule and one di­methyl­form­amide solvent mol­ecule. One triazine mol­ecule is disordered over two conformations within the crystal, the occupancies being 62 (1) and 38 (1)%. The phenyl ring of this mol­ecule resolves into two conformations rotated by almost 180° about the bridging bond between the two rings, while the triazine rings approximately superimpose on each other. The triazine mol­ecules of the asymmetric unit differ in the dihedral angles between their respective phenyl and triazine ring planes, these being 57.6 (2)° for the fully occupied, and 76.9 (6) and 106.8 (8)° for the partially occupied mol­ecules. An extensive network of hydrogen bonds maintains the crystal structure.     

Two regioisomers of condensed thioheterocyclic triazine synthesized from 6‐phenyl‐3‐thioxo‐2,3,4,5‐tetrahydro‐1,2,4‐triazin‐5‐one

In the crystal structure of 6‐phenyl‐3‐thioxo‐2,3,4,5‐tetrahydro‐1,2,4‐triazin‐5‐one, C₉H₇N₃OS, (I), the 1,2,4‐triazine moieties are connected by face‐to‐face contacts through two kinds of double hydrogen bonds (N—H...O and N—H...S), which form planar ribbons along the a axis. The ribbons are crosslinked through C—H...π interactions between the phenyl rings. The molecular structures of two regioisomeric compounds, namely 6‐phenyl‐2,3‐dihydro‐7H‐1,3‐thiazolo[3,2‐b][1,2,4]triazin‐7‐one, C₁₁H₉N₃OS, (II), and 3‐phenyl‐6,7‐dihydro‐4H‐1,3‐thiazolo[2,3‐c][1,2,4]triazin‐4‐one, C₁₁H₉N₃OS, (III), which were prepared by the condensation reaction of (I) with 1,2‐dibromoethane, have been characterized by X‐ray crystallography and spectroscopic studies. The crystal structures of (II) and (III) both show two crystallographically independent molecules. While the two compounds are isomers, the unit‐cell parameters and crystal packing are quite different and (II) has a chiral crystal structure.     

Molecular Structure and a Density Functional Theoretical Study on 2‐Nitroimino‐5‐Nitro‐Hexahydro‐1,3,5‐Triazine (NNHT)

2‐Nitroimino‐5‐nitro‐hexahydro‐1,3,5‐triazine (NNHT), was synthesized and its structure was determined by single‐crystal X‐ray diffraction. The crystal is monoclinic, space group P2₁/c with crystal parameters of a = 9.4031(13) Å, b = 8.5891(12) Å, c = 9.0200(13) Å, β = 91.213(2)°, V = 728.33(18) ų, Z = 4, F(000) = 392, D_c = 1.734 g/cm³. The experimental geometry of NNHT was input to Gaussian‐03W program and optimized using DFT‐B3LYP/6‐311++G** method. The IR frequencies and NMR chemical shift were carried out and compared well with those of the experimental. The atomic net charges and the population analysis are discussed. The heat of formation (HOF) for NNHT was evaluated by designing an isodesmic reaction. The detonation velocity (D) and detonation pressure (P) were estimated by using the well known Kamlet‐Jacobs equation, based on the theoretical HOF.     

Synthese und Kristallstruktur von 2‐Azido‐4,6‐dichloro‐s‐triazin

Synthesis and Crystal Structure of 2‐Azido‐4,6‐dichloro‐s‐triazine Single crystals of 2‐azido‐4,6‐dichloro‐s‐triazine were obtained from a reaction between cyanuric chloride and sodium azide. The structure of this compound was determined by single crystal X‐ray diffraction. 2‐Azido‐4,6‐dichloro‐s‐triazine crystallizes in the orthorhombic space group Pbca (no. 61), Z = 8, a = 746.48(8) pm, b = 952.6(1) pm, c = 2001.6(2) pm. The crystal structure contains (C₃N₃)(N₃)Cl₂ molecules being arranged in a tape‐like fashion, with tapes running along a‐axis direction. The tapes are combined with each other by interlocking azide‐ligands including an angle of approximately 90°. This arrangement leads to the formation of corrugated layers in the crystal structure.     

Synthesis,Characterization and Molecular Structure of a New Tetrameric Palladium(II) Complex Containing Schiff‐Bases Derived from AMTTO (AMTTO = 4‐amino‐6‐methyl‐1,2,4‐triazine‐thione‐5‐one)

The reactions of AMTTO = 4‐amino‐6‐methyl‐1,2,4‐triazine‐thione‐5‐one (AMTTO, 1 ) with 2‐hydroxybenzaldehyde (salicylaldehyde) and 4‐hydroxybenzaldehyde in methanol under reflux conditions led to the corresponding Schiff‐bases ( H₂L1 and H₂L2 ). The reaction of H₂L1 with palladium acetate in ethanol and additional recrystallization from toluene gave the tetrameric complex [Pd(L)]₄·2C₇H₈ ( 2 ). All compounds were characterized by infrared spectroscopy, elemental analyses as well as by X‐ray diffraction studies. Crystal data for H₂L1 at ?80 °C: space group P2₁/c with a = 1285.4(1), b = 707.7(1), c = 1348.2(1) pm, β = 109.32(1)°, Z = 4, R₁ = 0.0328, H₂L2 at ?80 °C: space group P4₃2₁2 with a = 762.5(1), b = 762.5(1), c = 4038.9(2) pm, Z = 8, R₁ = 0.025 and for 2 at ?103 °C: space group C2/c with a = 2862.5(6), b = 2847.6(6), c = 1727.8(4) pm, β = 105.18(3)°, Z = 8, R₁ = 0.0704.     

Synthesis of 1,2,4‐triazolo[1,5‐d]‐1,2,4‐triazine‐5‐thiones

In an attempt to discover bicyclic compounds containing the 1,2,4‐triazine moiety, 1,2,4‐triazolo[1,5‐d]‐1,2,4‐triazine‐5‐thiones from one pot reaction of arylnitriles with 4‐amino‐1,2,4‐triazine‐3‐thione‐5‐one in the presence of potassium tert‐butoxide were synthesized.     

2,4‐Diamino‐5‐(1‐naphthyl)‐3,5‐diaza‐1‐azoniaspiro[5.5]undeca‐1,3‐diene chloride

The title salt, C₁₈H₂₂N₅⁺·Cl^?, is a member of a new series of lipophilic 4,6‐di­amino spiro‐s‐triazines which are potent in­hib­itors of di­hydro­folate reductase. The protonated triazine ring deviates from planarity, whereas the cyclo­hexane ring adopts a chair conformation. A rather unusual hydrogen‐bonding scheme exists in the crystal. There is a centrosymmetric arrangement involving two amino groups and two triazine ring N atoms, with graph‐set R(8) and an N?N distance of 3.098 (3) Å, flanked by two additional R(8) systems, involving two amino groups, a triazine ring N atom and a Cl^? anion, with N?Cl distances in the range 3.179 (2)–3.278 (2) Å. Furthermore, the Cl^? anion, the protonated triazine ring N atom and an amino group form a hydrogen‐bonding system with graph‐set R(6).     

Hydrogen bonding structure and many‐body interactions in 1,3,5‐triazine–(water)3 and 1,2,4‐triazine–(water)3 complexes

The hydrogen bonding structure and many‐body interactions between 1,3,5‐triazine (1,2,4‐triazine) and three water molecules are studied using the density functional theory (DFT) B3LYP method and 6‐31++G** basis set. Various structures of 1,3,5‐triazine–(water)₃ and 1,2,4‐triazine–(water)₃ complexes are investigated, and the seven and eight stable structures are reported for 1,3,5‐triazine–(water)₃ and 1,2,4‐triazine–(water)₃, respectively. Many‐body analysis is also carried out to obtain relaxation energy and many‐body interaction energy (two‐, three‐, and four‐body), and the most stable conformer has the basis set superposition error corrected interaction energy of ?92.09 and ?99.53 kJ/mol. The two‐ and three‐body interactions have significant contribution to the total interaction energy, whereas the relaxation energy, four‐body interactions are very small for 1,3,5‐triazine–(water)₃ and 1,2,4‐triazine–(water)₃ complexes. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007     

Synthesis,Characterization and Crystal Structure of a Silver(I) Complex containing AMTT (AMTT = 4‐amino‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)‐thione)

The reaction of 4‐amino‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)‐thione with AgNO₃ in methanol led to the complex [Ag(ATT)₂]NO₃ ( 2 ). 2 was characterized by elemental analyses, IR, ¹HNMR and Raman spectroscopy as well as single‐crystal X‐ray diffraction. Crystal data for 2 at ?70 °C: space group P2₁/n with a = 1356.7(12), b = 770.4(7), c = 1475.2(12) pm, β = 111.730(15)°, Z = 4, R₁ = 0.0402.     

Interaction of 4‐Oxo‐4H‐pyrazolo[5,1‐c][1,2,4]triazin‐1‐ides with Grignard Reagents

Reactions of magnesium 3‐tert‐butyl‐8‐R‐4‐oxo‐4H‐pyrazolo[5,1‐c][1,2,4]triazin‐1‐ides (R = CN, CO₂Et) with AlkMgBr led to nucleophilic additions to either side chain or triazine core, with selectivity being dependent on the nature of substituents, as well as on the solvents used. Previously inaccessible C⁸‐functionalized and C⁴‐functionalized pyrazolo[5,1‐c][1,2,4]triazines and 3‐tert‐butyl‐3‐ethyl‐4‐oxo‐1,2,3,4‐tetrahydropyrazolo[5,1‐c][1,2,4]triazine were synthesized, and their reactivity and spectral data discussed.     

4‐Amino‐7‐(2‐de­oxy‐2‐fluoro‐β‐d‐arabinofuranos­yl)‐5‐fluoro‐7H‐pyrrolo[2,3‐d]pyrimidine: a bis‐fluorinated analogue of 2′‐deoxy­tubercidin

The title compound, C₁₁H₁₂F₂N₄O₃, exhibits an anti glycosylic bond conformation, with a torsion angle χ = −117.8 (2)°. The sugar pucker is N‐type (C4′‐exo, between ³T₄ and E₄, with P = 45.3° and τ_m = 41.3°). The conformation around the exocyclic C—C bond is −ap (trans), with a torsion angle γ = −177.46 (15)°. The nucleobases are stacked head‐to‐head. The crystal structure is characterized by a three‐dimensional hydrogen‐bond network involving N—H⋯O, O—H⋯O and O—H⋯N hydrogen bonds.     

Synthesis,Characterization and Crystal Structure of the Dimeric Silver(I) Complex containing 4‐Amino‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)‐thione

The reaction of 4‐amino‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)‐thione (AMTT, 1 ) with AgNO₃ and triphenylphosphane in a molar ratio 1:1:2 in ethanol led to the dimeric complex {[Ag(AMTT)(PPh₃)₂]NO₃}₂·4EtOH ( 2 ). 2 was characterized by elemental analyses, IR, ³¹P NMR spectroscopy as well as single crystal X‐ray diffraction. Crystal data for 2 at ?80 °C: space group with a = 1265.5(2), b = 1300.9(2), c = 1509.5(2) pm, α = 83.77(2)°, β = 79.22(2)°, γ = 62.89(2)°, Z = 2, R₁ = 0.0330.     

Green synthesis and crystal structure of 4,7‐diaryl‐2‐oxo(thio)‐1,2,3,4,5,6,7,8‐octahydroquinazoline‐5‐one derivatives

A green and convenient approach to the synthesis of novel 4,7‐diaryl‐2‐oxo(thio)‐1,2,3,4,5,6,7,8‐octahydroquinazoline‐5‐one derivatives from appropriate aromatic aldehydes and 5‐aryl‐1,3‐cyclohexanedione with urea or thiourea in the presence of dilute HCl as catalyst in water is described. This method provides several advantages such as environmental friendliness, low cost, high yields, and simple workup procedure. The structures of all compounds were characterized by elemental analysis, IR, MS, and ¹H NMR. The crystal and molecular structure of 4‐(4′‐chlorophenyl)‐7‐(4′‐methoxyphenyl)‐1,2,3,4,5,6,7,8‐octahydroquinazoline‐2,5‐dione 5m have been determined by single crystal X‐ray diffraction analysis. The crystal of compound 5m belongs to monoclinic with space group P‐2₁/c, a = 1.4353 (4) nm, b = 1.4011 (4) nm, c = 0.9248 (3) nm, α = 90.00°, β = 101.242 (6)°, γ = 90.00°, Z = 4, V = 1.8241 (9) nm³, R₁ = 0.0448, and wR₂ = 0.1022. J. Heterocyclic Chem., (2011).     

Synthesis, Structure and Biological Activities of S-[α-（ 4-Methoxyphenylcarbonyl ）-2-（1,2,4-triazole-l-yl） ethyl-N, N-dime-thyldithiocarbamate

The title compound was prepared by reaction of N, N‐dimethyldithiocarbamate sodium with l‐bromo‐l‐(4‐methoxyphenylcarbonyl)‐2‐(1, 2, 4‐triazole‐l‐yl) ethane. Its crystal structure has been determined by X‐ray diffraction analysis. The crystal belongs to triclinic with space group Pī, a = 0.7339(2) nm, b = 1.1032(2) nm, c = 1.1203(2) nm, a = 90.27(3)°, β = 102.03(3)°, γ = 104.91(3)°, Z=2, V = 0.8556(3) nm³, D_c = 1.360 g/cm³, μ =0.325 mm^?1, F(000)=368, final R₁ =0.0475. The planes of 4‐methoxybenzyl group and triazole ring are nearly perpendicular to each other. The dihedral angle is 83.97°. There is an obvious π‐π stacking interaction between the molecules in the crystal lattice. The results of biological test show that the title compound has fungicidal and plant growth regulating activities.     

7‐Deaza‐2,8‐diaza­adenosine

In the title compound [systematic name: 4‐amino‐7‐(β‐d ‐ribofuranos­yl)‐7H‐pyrazolo[3,4‐d][1,2,3]triazine], C₉H₁₂N₆O₄, the torsion angle of the N‐glycosylic bond is high anti [χ = −83.2 (3)°]. The ribofuran­ose moiety adopts the C2′‐endo–C1′‐exo (²T₁) sugar conformation (S‐type sugar pucker), with P = 152.4° and τ_m = 35.0°. The conformation at the C4′—C5′ bond is +sc (gauche,gauche), with the torsion angle γ = 52.0 (3)°. The compound forms a three‐dimensional network that is stabilized by several hydrogen bonds (N—H⋯O, O—H⋯N and O—H⋯O).     

Chlorine‐Induced Hydrogen‐Bonding Network of A Novel Dimer Based on Nickel and Tridentate Ligand: 3‐Hydrazine‐4‐amino‐1,2,4‐Triazole

The reaction of NiCl₂ and 3‐hydrazine‐4‐amino‐1,2,4‐triazole (Hatr) in the mixed solvent of EtOH and H₂O yielded a dimer compound ([Ni₂(Hatr)₂(H₂O)₂(EtOH)₂Cl₂]Cl₂·EtOH) with water and EtOH molecules coordinated to nickle ions. It crystallized in trigonal space group R‐3, a=b=29.67(1) Å, c=8.95(7) Å, β=120(1)°, as determined by single‐crystal X‐ray diffraction. Then, they were fully characterized by the IR spectroscopy, differential scanning calorimetry (DSC), thermogravimetry (TG), and elemental analysis.     

Synthesis,Characterization and Crystal Structure of 4‐Amino‐1,2,4‐Δ2‐triazoline‐5‐thione and its Silver(I) Complex

The reaction of 4‐amino‐1,2,4‐Δ²‐triazoline‐5‐thione (ATT, 1 ) with AgNO₃ in methanol led to the complex [Ag(ATT)₂]NO₃ ( 2 ). 2 was characterized by elemental analyses, ¹H NMR, IR, and Raman spectroscopy as well as single‐crystal X‐ray diffraction. The molecular structure of 1 was also determined by single crystal X‐ray analysis. Crystal data for 1 at ?80 C: space group C2/c with a = 2107.4(2), b = 1425.1(1), c = 688.4(1) pm, β = 104.55(1)°, Z = 16, R₁ = 0.0514, crystal data for 2 at ?80 °C: space group P2₁/c with a = 675.7(1), b = 1321.1(1), c = 1311.2(1) pm, β = 90.03(1)°, Z = 4, R₁ = 0.0437.