Synthesis of 3-Azido-5-amino-1,2,4-triazole

3-Azido-5-amino-1,2,4-triazole was obtained from 3,5-diamino-1,2,4-triazole in two ways: by partial diazotization-substitution directly in the substrate or at its primarily nitrosation, and also with the use of direct or indirect protection of an amino group with subsequent conversion into azido compound followed by deprotection.     

Regioselective single-reactor synthesis of arylsulfonyl derivatives of 3,5-diamino-1,2,4-triazole

Arylsulfonylation of 1-acetyl-3,5-diamino-1,2,4-triazole with arylsulfonyl chlorides in pyridine, with the subsequent hydrolysis of the acetyl group, was studied; a new regioselective method for synthesis of N-(5-amino-1H-1,2,4-triazol-3-yl)arylsulfonamides was developed.     

Complexes derived from 4-amino-3-methyl-5-thione-1,2,4-triazole and monoorganomercury moieties. Crystal structure of (4-amino-5-mercapto-3-methyl-1,2,4-triazolato)methylmercury(II)

The compounds [HgR(L)] (R = Me or Ph; L = 4-amino-5-mercapto-3-methyl-1,2,4-triazolate) have been prepared and the crystal structure of the methylmercury(II) compound determined. This compound crystallizes in the monoclinic space group P21/n with a = 5.087(1), b = 10.102(1), c = 16.167(2) Å, β = 98.56(1)°, Z = 4 (R = 0.027; R_w = 0.030). It is formed of molecules in which the triazolate anion is bound to mercury strongly via the S atom and weakly via the amine N; there is also a weak intermolecular interaction between the endocyclic N and the Hg atom of a neighbouring unit.     

Synthesis of 3-pyridyl-substituted 5-amino-1,2,4-triazoles from aminoguanidine and pyridinecarboxylic acids

Effect of the molar ratio between reagents, temperature, and synthesis duration on the yield of 3-pyridylsubstituted 5-amino-1,2,4-triazoles in the reaction of aminoguanidine hydrochloride with pyridinecarboxylic acids under acid catalysis conditions was studied. A single-reactor method for synthesis of 3-pyridyl-substituted 5-amino-1,2,4-triazoles and their hydrochlorides was developed.     

N-Amination of 3-amino-1,2,4-triazole with hydroxylamine-O-sulfonic acid: Synthesis of 1,5-diamino-1,2,4-triazole

N-Amination of the 3(5)-amino-1,2,4-triazolide anion with hydroxylamine-O-sulfonic acid is studied. This method provided an access to the previously unknown 1,5-diamino-1,2,4-triazole.     

A survey of the lone pair effect on the ring geometry of 1,2,4-triazoles and analogous 1,2,3-triazoles and imidazoles : The structures of 1-methyl-5-amino-3-methylthio-1,2,4-triazole, 1-phenyl-5-amino-3-methylthio-1,2,4-triazole and 1-(4-methylbenzyl)-3-amino-5-methylthio-1,2,4-triazole

The structures of the title compounds have been established by X-ray crystallography from diffractometer data. Crystals of the first (I), C₄H₈N₄S, are monoclinic, space group P2₁/c, with a = 8.166(2), b = 10.481(1), c = 8.585(1) Å, β = 109.33(2)°, Z = 4, D_c = 1.381 g cm⁻³. Crystals of the second (II), C₉H₁₀N₄S, are monoclinic, space group P2₁/c, with a = 11.850(4), b = 7.898(1), c = 23.981 (6) Å, β = 117.23(2)°, Z = 8, D_c = 1.373 g cm⁻³. Crystals of the third (III), C₁₁H₁₄N₄S₁ are also monoclinic, space group P2₁/c with a = 12.829(3), b = 8.348(1), c = 11.088(4) Å, β = 94.40(4)°, Z = 4, D_c = 1.314 g cm⁻³. The structures, determined by direct methods (I, III) and Patterson synthesis (II) were refined to R = 0.039 for 1070 reflections of I, R = 0.040 for 2792 reflections of II and R = 0.041 for 1900 reflections of III. The characteristic features of the planar five-membered rings are studied in comparison with the analogous 1,2,3-triazoles and imidazoles. It is shown that these planar rings exhibit only two patterns of the endocyclic bond angles induced dominantly by the number and relative position of the N-lone pairs. A similar effect of the double bonds (attached to C atoms) is also discussed.     

Acyl derivatives of 3-amino-1,2,4-triazole

Only 3-acylamino-1,2,4-triazoles were isolated in the acylation of 3-amino-1,2,4-triazole with acid chlorides that contain strong electron acceptor substituents. Acylation takes place in the 2 position when aliphatic and aromatic acid chlorides are used as the acylating agents. The action of methoxy- and ethoxyformyl chlorides leads to the formation of 1- and 2-alkoxycarbonyl-3-amino-1,2,4-triazoles. When N-acyl-3-amino-1,2,4-triazoles are heated, they undergo intermolecular trans-aminoacylation to 3-acylamino-1,2,4-triazoles, which exist in the solid phase in the form of amido and imido tautomers. Under the conditions of massspectroscopic analysis the percentage of the imido form increases as the electronacceptor capacity of the substituent increases.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1414–1419, October, 1980.     

Optimization of the synthesis of 5-amino-1,2,4-triazol-3-ylacetic acid and bis(5-amino-1,2,4-triazol-3-yl)methane

The influence of the molar ratio and concentration of the reactants and of the temperature and time of the synthesis on the yield of malonic acid guanylhydrazides in the reaction of aminoguanidine with malonic acid in acidic aqueous solutions was examined, and improved procedures for preparing 5-amino-1,2,4-triazol-3-ylacetic acid and bis(5-amino-1,2,4-triazol-3-yl)methane were suggested.     

Reaction of arylidene derivatives of Meldrum's acid with 3-amino-1,2,4-triazole

The condensation of arylidene derivatives of Meldrum's acid with 3-amino-1,2,4-triazole in nitrobenzene leads to 4,5,6,7-tetrahydro-1,2,4-triazolo [1,5-a]pyrimidin-5-ones. In DMF the reaction proceeds with the formation of arylsubstituted N-(2H-1,2,4-triazol-3-yl)-3-(2H-1,2,4-triazol-3-ylamino)propionamides. Ukrainian Research Institute for the Pharmacotherapy of Endocrine Diseases, Kharkov 310002. Kharkov State University, Kharkov 310077, Ukraine     

N-cyanamidopyrroles and N-cyanamidoimines from 4-amino-1,2,4-triazole

Novel, useful, and unstable cyanamides including the title compounds have been made cleanly from readily available 1-substituted-1,2,4-triazoles by titration with n-BuLi.     

Reaction of ethyl cyanoacetate with 4-amino-3 mercapto-5R-1,2,4-triazole

Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 137–138, January, 1994.