2-(Morpholin-4-yl)-4,5-bis(2’’,2’’,2’’-trinitroethoxy)-1,3,5-triazine having QSAR-predicted anti-tumor activity was tested for the cytotoxicity using MTT and LDH cell viability tests. The experiments were conducted using human fibroblasts, peripheral blood mononuclear cells and breast cancer cells and allowed to identify effective cytotoxic concentration ant therapeutic range of this compound. The data obtained suggest the feasibility of the further studies of the test compound as a potential anti-cancer agent.

It was shown for the first time that in the reaction of 3-methyl-5-(trinitromethyl)tetrazolo[1,5-a][1,3,5]triazin-7-one with alcohols in the presence of bases, along with the expected substitution of the trinitromethyl group, opening of the 1,3,5-triazine ring with the addition of an alcohol at the site of the C–N bond cleavage takes place. It was found that in the absence of bases only opening of the 1,3,5-triazine ring occurs with the formation of alkyl esters of {1-[(1-methyl-1H-tetrazol-5-yl)imino]-2,2,2-trinitroethyl}carbamic acid, and the trinitromethyl group retains high reactivity and can be substituted by the action of alcohols in the presence of a base.

It is well known that the densest molecular crystals formed by molecules consisting of C, H, N, O, and F atoms are those of polynitro compounds that do not and cannot participate in strong intermolecular interactions. At the same time, many “typical” organic crystals are also stabilized by weak intermolecular contacts, such as C–H···O(N), O(N)···π, H···H, and so forth. However, the density of such crystals is significantly lower. In this work, we report the synthesis and properties of 1,3,5-triazine derivatives containing both trinitromethyl and/or trinitroethoxy, as well as isopropoxy groups. It was shown by X-ray structural analysis and quantum chemistry calculations that the crystal structures of the obtained 1,3,5-triazine derivatives were stabilized by weak interactions only, such as NO2···NO2, O···π, C–H···O, C–H···N, and H···H contacts. The effects from various types of weak intermolecular contacts on crystal density were evaluated. No strong correlation was found between the energy of interactions, decrease of system volume caused by such interactions, and an increase in crystal density. It was demonstrated that crystal packing can be studied effectively by a recently proposed method via the analysis of ΔOED criterion describing the density increase of molecule and its fragments upon crystal formation from isolated molecules.

Co-crystallization is an elegant technique to tune the physical properties of crystalline solids. In the field of energetic materials, co-crystallization is currently playing an important role in the engineering of crystals with improved performance. Here, based on an analysis of the structural features of the green primary explosive, tetramethylammonium salt of 7-oxo-5-(trinitromethyl)-4,5,6,7-tetrahydrotetrazolo[1,5-a][1,3,5]triazin-5-ide (1), a co-former such as the powerful secondary explosive, benzotrifuroxan (BTF, 2), has been proposed to improve it. Compared to the original 1, its co-crystal with BTF has a higher detonation pressure and velocity, as well as an initiating ability, while the impact sensitivity and thermal stability remained at about the same level. Both co-formers, 1 and 2, and co-crystal 3 were characterized by single-crystal X-ray diffraction and their crystal packing was analyzed in detail by the set of approaches, including periodic calculations. In the co-crystal 3, all intermolecular interactions were significantly redistributed. However, no new types of intermolecular interactions were formed during co-crystallization. Moreover, the interaction energies of structural units in crystals before and after co-crystallization were approximately the same. A similar trend was observed for the volumes occupied by structural units and their densifications. The similar nature of the organization of the crystals of the co-formers and the co-crystal gives grounds to assert that the selected co-formers are an ideal pair for co-crystallization, and the invariability of the organization of the crystals was probably responsible for the preservation of some of their properties.

Being a liquid at room temperature, the crystalline form of 3,4-dinitrofurazan (DNF) has long been the subject of theoretical predictions. Its detonation performance in the solid state was calculated based on very high crystal density (1.89-2.02 g/cm(3)) predicted by different theoretical schemes. Using zone melting technique, we were able to grow a DNF single crystal of suitable quality for X-ray diffraction study. The experimental density was found to be 1.917 g/cm(3) at 100 K, which corresponds to 1.85 g/cm(3) at room temperature, that is lower than erlier predictions. We found that the ortho-nitro groups of DNF are not equivalent and behave differently upon the crystal structure formation, which was not taken into account in the theoretical estimates carried out earlier. It has now been shown that using the Delta(OED)-based densification approach, this "ortho-effect" can be clarified and quantified. The observed effect is probably characteristic of all polynitro compounds, where nitro groups are brought together, and should be kept in mind when constructing high density materials.

A technology has been developed for producing an asphalt binder for road construction based on oil distillation residues modified with elemental sulfur. A blend of asphalt base and elemental sulfur was exposed to the action of ultrasound with a vibratory power of 2.5 W/cm2 and a frequency of 20 kHz at 160°C. The blend was heated exclusively by acoustic vibration energy. Sulfur-asphalt samples conforming to the BND 130/200 brand were obtained. Energy consumption can be reduced and asphalt binder production process can be accelerated by ultrasonic blending.

The reaction of 3-methyl-5-trinitromethyltetrazolо[1,5- а ][1, 3, 5]triazin-7-one with water led to the opening of 1,3,5-triazine ring and preservation of trinitromethyl group in the product. The obtained N -(1-methyltetrazol-5-yl)trinitroacetimidamide is of interest as highenergy compound.

This review covers the methods applicable for the synthesis of (dinitromethyl)azines: nitration of azine derivatives, azine ring formation,nucleophilic su bstitution in azine rings by the action of dinitrocarbanions, and denitration of trinitromethylazines. Further reactions with the conservation of dinitromethyl group, as well as its transformations into other functional groups, or modification of other substituents in (dinitromethyl)azines are also considered. Dinitromethylazines are of interest as energetic materials with low sensitivity and as biologically active compounds.

A simple and convenient method for the preparation of 2,4-disubstituted 1,3,5-triazine-nitrolic acids has been developed. The first example of nitrolic acid with Z-configuration was revealed by X-ray crystallographic analysis.

Samara State Technical University, Samara N. D. Zelinsky Institute of Organic Chem Leninsky Prosp, Moscow 119991, Russian F A. N. Nesmeyanov Institute of Organoele Science, Moscow 119991, Russian Federatio Institute of Problems of Chemical Ph Chernogolovka, Moscow Region, 142432 Ru † Electronic supplementary information (E copies of H, C, N, and N NMR compounds, and description of intermole 1434738–1434740. For ESI and crystallog format see DOI: 10.1039/c6ra05826d Cite this: RSC Adv., 2016, 6, 34921

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

An efficient and reliable synthesis of 2,4,6-tris(2-fluoro-2,2-dinitroethoxy)-1,3,5-triazine (1) has been developed. The ether 1 was fully characterized by IR and multinuclear NMR spectroscopy, and X-ray crystal structure determinations. The compound exhibits good density, excellent thermal stability, and high performance, while impact sensitivities are comparable to TNT.

The results of pioneering research on the alkylation of fused [1,2,4]triazolo[1,5- a ][1,3,5]triazine system are presented, including computational studies of the reaction between 5-dimethylamino[1,2,4]triazolo[1,5- a ][1,3,5]triazin-7(3 H )-one and bromoethane. The reaction of 5-amino-substituted [1,2,4]triazolo[1,5- a ][1,3,5]triazin-7(3 H )-ones with allyl bromide, bromoethane, or (2-acetoxyethoxy)methyl bromide occurred selectively with the formation of products due to alkylation at the N-3 nitrogen atom of the heterocyclic system. The removal of acetyl protecting group from 5-amino-substituted {2-[(7-oxo[1,2,4]triazolo[1,5- a ][1,3,5]triazin-3(7 H )-yl)methoxy]ethyl}acetates gave 5-aza analogs of acyclovir, containing a substituted amino group at position 5 of the heterocyclic 3-[(2-hydroxyethoxy)methyl][1,2,4]-triazolo[1,5- a ][1,3,5]triazin-7(3 H )-one system.

The alkylation reactions of fused tetrazolo[1,5- a ][1,3,5]triazine system were studied. The results of quantum-chemical calculations for the reaction of 5-(dimethylamino)tetrazolo[1,5- a ][1,3,5]triazin-7(3 H )-one with ethyl bromide are presented. The reactions of 5-aminosubstituted tetrazolo[1,5- a ][1,3,5]triazin-7(3 H )-ones with ethyl-, butyl-, and allyl halides led to the formation of products due to alkylation at the N-3 nitrogen atom of the ring system, 3-alkyl-5-amino-substituted tetrazolo[1,5- a ][1,3,5]triazin-7(3 H )-ones, as well as products due to alkylation at the exocyclic oxygen atom with tetrazole ring opening, 2-amino-substituted 6-alkoxy-4-azido-1,3,5-triazines. Besides that, the product that was alkylated at the ring N-3 nitrogen atom underwent hydrolytic cleavage of the 1,3,5-triazine ring with elimination of the carbonyl functional group and formation of N -(1-alkyl-1 H -tetrazol-5-yl)- N '-alkyl- and N -(1-alkyl-1 H -tetrazol-5-yl)- N ', N '-dialkylguanidines.

The multicomponent reaction of 2,4,6-trichloro-1,3,5-triazine with potassium trinitromethane and trinitroethanol was exploited for the first synthesis of the hetaryl trinitroethyl ethers.

Reaction of 5-dimethylaminotetrazolo[1,5- а ][1,3,5]triazin-7-one tetrabutylammonium salt with allyl bromide in acetonitrile proceeds with the formation of 3-allyl-5-dimethylaminotetrazolo[1,5- a ][1,3,5]triazin-7-one ( N -alkylation), 6-allyloxy-4-azido- N , N -dimethyl-1,3,5-triazin-2-amine ( O -alkylation), and 2-(1-allyl-1 H -tetrazol-5-yl)-1,1-dimethylguanidine as the product of hydrolysis of N -alkylated tetrazolo[1,5- a ][1,3,5]triazin-7-one. The structure of the reaction products was confirmed by IR, 1 H and 13 C NMR spectroscopy as well as elemental and X-ray structural analysis data.

The cyclization of (II) in the presence of (III) occurs stereoselectively to give only the [1,5‐a]‐isomer, albeit formation of two tautomers may take place depending on the 5‐amino substituent.

The oxidative cyclization of 4-amino-substituted 6-arylidene(hetarylmethylidene)hydrazinyl-1,3,5-triazin-2-ones with lead(IV) tetraacetate proceeds via a Dimroth-type rearrangement to give 5-amino-substituted 2-aryl(hetaryl)-1,2,4-triazolo[1,5-a]-1,3,5-triazin-7-ones. IR, NMR, and X-ray studies have shown that the only products of the reactions were the [1,5-a]-isomers.

Treatment of triazinones (I) with NaN3 provides sodium salts (II) instead of expected azides.