Synthesis of analogs of 5(4)-aminoimidazole-4(5)-carboxamide and purines. 9. peculiarities of the reaction of 5(4)-aminoimidazole-4(5)-carboxhydrazide with nitrous acid and of 5-diazoimidazole-4-carboxazide with amines

The reaction of 5(4)-aminoimidazole-4(5)-carboxhydrazide with nitrous acid was investigated. A mixture of four compounds, viz., 5-diazoimidazole-4-carboxazide, 5-diazoimidazole-4-carboxylic acid, 5(4)-aminoimidazole-4(5)-carboxazide, and 2-azahypoxanthine, is formed under all of the investigated conditions, 5(4)-Azidoimidazole-4(5)-carboxamide derivatives were obtained in the reaction of diazoimidazole-carboxazide with various amines in protic and aprotic solvents. 5-N-(Piperidyl)-azoimidazole-4-carboxazide was isolated only in the reaction with piperidine in an aqueous medium.See [1] for Communication 8.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1536–1540, November, 1980.     

Synthesis of analogs of 5(4)-aminoimidazole-4(5)-caeboxamide and purines

4(5)-Sulfonyl chlorides, which were converted to the corresponding sulfamoyl derivatives, were obtained from the amide and ethyl ester of 4(5)-mercaptoimidazole-5(4)-carboxylic acid by oxidative chlorination. The azide of 4(5)-sulfamoylimidazole-5(4)carboxylic acid was synthesized through 4(5)-sulfamoylimidazole-5(4)-carboxylhydrazide, and its conversion in various media to 5(4)-aminoimidazole-4(5)-sulfonamide derivatives and to 3,4-dihydro-3-oxoimidazo[4,5-e]-1,2,4-thiadiazine 1,1-dioxide was studied.See [1] for communication V.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1119–1122, August, 1976.     

Synthesis of analogs of 5(4)-aminoimidazole-4(5)-carboxamide and purines

5-Diazoimidazole-4-carboxazide was isolated in the diazotization of 5(4)-aminoimidazole-4(5)-carboxhydrazide. The diazotization of N-substituted hydrazides of 5(4)-aminoimidazole-4(5)-carboxylic acis was studied. It is shown that the resulting diazo derivatives undergo cyclization to 3-arylideneaminoimidazo[4,5-d]-1,2,3-triazin-4-ones.See [1] for communication 7.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 984–985, July, 1979.     

Synthesis and properties of analogs of 5(4)-aminoimidazole-4(5)-carboxamide and purines. 14. Acylation of 5(4)-aminoimidazole derivatives

The acylation of 5(4)-aminoimidazole derivatives was studied. It is shown that acylation by means of carboxylic acid anhydrides and chlorides takes place at the amino group, whereas acylation by means of chlorocarbonic acid esters takes place at the nitrogen atoms of the imidazole ring. Methods for the selective introduction of a carbomethoxy group in the 1, 3, and 5 positions of the 5(4)-aminoimidazole-4(5)-carboxamide molecule were developed.See [1] for communication 13.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 247–252, February, 1984.     

The decomposition mechanism of new solid-state 4(5)-aminoimidazole-5(4)-carboxamide coordination compounds

Imidazole ring coordination compounds are very useful models to better understand the coordination properties and the reaction mechanisms of biologically important systems. On the basis of previous work, new Co(II)-, Ni(II)- and Cu(II)-4(5)-aminoimidazole-5(4)-carboxamide coordination compounds have been synthesized and characterized by elemental analysis, UV-Vis and IR spectroscopies. Their thermal stability was determined by differential scanning calorimetry and by thermogravimetry, and the decomposition mechanisms were investigated by evolved gas analysis (EGA).     

Synthesis and properties of analogs of 5(4)-aminoimidazole-4(5)-carboxamide and purines. 15. Ring opening in imidazo[4,5-d]-1,2,3-triazines

It has been shown that 4-methylthio-, ethoxy-, and methoxyimidazotriazines and imidazotriazin-4-ones, unlike benzo-1,2,3-triazines, do not display cryptodiazonium behavior. A novel type of fission of the triazine ring to give esters and thioesters of 5-aminoimidazole-4-carboxylic acid is described.For Communication 14, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1248–1250, September, 1989.     

The reaction of 5-aminoimidazole-4-carbohydrazides with orthoesters

The reaction of 5-aminoimidazole-4-carbohydrazides with orthoesters is shown to yield 1-amino-9-alkyl-hypoxanthines. Similar reaction of anthranilic acid hydrazide is shown to yield 3-amino-4-quinazolone, and not 1,4-dihydro-5H-1,3,4-benzotriazepin-5-one as previously reported.     

Synthesis of analogs of 5(4)-aminoimidazole-4(5)-carboxamide and purines

The corresponding 5(4)-mercaptoimidazoles, from which various 5(4)-mercaptoimidazole-4(5)-carboxylic acid derivatives were synthesized, were obtained from the amide and ethyl ester of 5-diazoimidazole-4-carboxylic acid by substitution of the diazo group. 5-Diazo-imidazole-4-hydroxamic acid does not undergo substitution with sodium disulfide but does undergo cyclization to 3-N-hydroxyimidazo[4,5-d]-1,2,3-triazin-4-one under these conditions. The kinetics of the cyclization of diazoimidazoles were studied, and the interrelationship between the structure and reactivity of the latter was examined.See [1] for communication III.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1550–1554, November, 1975.     

Synthese von 4(5)-acyl-5(4)-alkylimidazolen aus symmetrischen 1,3-dicarbonylverbindungen

Synthesis of 4(5)-Acyl-5(4)-alkylimidazoles from Symmetrical 1,3-Diones A new synthesis of 4(5)-acyl-5(4)-alkylimidazoles 1 is described. The symmetrical 1,3-diones 5a and 5b were reacted with N₂O₄ to give the nitro compounds 7a and 7b , respectively; 5c was treated with NaNO₂ to give the nitroso compound 7c (Scheme 2). Hydrogenation of 7a , 7b and 7c over Pd/C in acetic acid/acetic formic anhydride yielded the formamides 9a , 9b and 9c , whose cyclization in formamide/formic acid afforded the 4(5)-acyl-5(4)-alkylimidazoles 1a, 1b and 1c , respectively. Oxazoles 11a and 11b were obtained from the corresponding formamides 9a and 9b with methanesulfonic acid/P₂O₅.     

Synthesis of 4(5)-substituted 2-amino-5(4)-hydroxyimino-5(4)H-imidazoles and their transformation into the corresponding 3-substituted 5-amino-1,2,4-oxadiazoles

Treatment of 4(5)-phenyl(or alkyl)-2-aminoimidazoles with isoamyl nitrite in acetic acid afforded the corresponding 4(5)-substituted 2-amino-5(4)-hydroxyimino-5(4)H-imidazoles which by heating in water were transformed into 3-benzoyl(or acyl)-5-amino-1,2,4-oxadiazoles.     

Reactions of 3-hydrazino-5,6-diphenyl-1,2,4-triazine with 4-arylidene-2-phenyl-5(4H)-oxazolones and 4-benzylidene-3-methyl-5(4H)-isoxazolone

3-Hydrazino-5,6-diphenyl-1,2,4-triazine reacts with 4-arylidene-2-phenyl-5(4H)-oxazolones in toluene to give substituted acrylic acid hydrazides, and in glacial acetic acid to give substituted imidazolones. On the other hand the hydrazinotriazine reacts with 4-benzylidene-3-methyl-5(4H)-isoxazolone, probably via a 1,4 addition reaction followed by an elimination reaction, to give benzaldehyde 5,6-diphenyl-1,2,4-triazin-3-ylhydrazone and 3-methyl-5(4H)-isoxazolone.     

Synthesis of 4(5)-hydroxymethylimidazoles by hydroxymethylation and decarboxylation of imidazole-4(5)-carboxylic acids

4(5)-Hydroxymethylimidazoles were prepared by hydroxymethylation and decarboxylation of imidazole-4(5)-carboxylic acid esters. The reaction was simply carried out with aqueous formaldehyde solution in the presence of base.     

Synthesis of ribonucleosides of 4(5)-cyano-5(4)-methylimidazole and related 4-substituted-5-methylimidazole ribosides

4-Cyano-1-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)-5-methylimidazole ( 4 ) and its corresponding 5-cyano-4-methyl substituted isomer ( 5 ) have been obtained by ribosylation of 4(5)-cyano-5(4)-methylimidazole ( 3 ) via the mercuric cyanide method or by ribosylation of the trimethylsilyl derivative of 3 . Treatment of 4 with methanolic ammonia, ammonium chloride in liquid ammonia and potassium hydrosulfide provided 4-cyano-1-β-D-ribofuranosyl-5-methylimidazole ( 6 ), 1-β-D-ribofuranosyl-5-methylimidazole-4-carboxamide ( 2 ) and 1-β-D-ribofuranosyl-5-methylimidazole-4-thiocarboxamide ( 11 ) respectively. Reaction of 6 with hydroxylamine afforded the corresponding 4-carboxamidoxime substituted nucleoside ( 13 ) which on catalytic reduction in the presence of ammonium chloride, was transformed into 1-β-D-ribofuranosyl-5-methylimidazole-4-carboxamidine ( 14 ) as hydrochloride salt.     

On the methylation of 5-(4-alkoxyphenyl)-15-(4-pyridyl)porphyrins

Mixed condensation of 3,3′-diethyl-4,4′-dimethyl-2,2′-dipyrrolylmethane 1 with 4-formylpyridine 2 and 4-alkoxybenzaldehyde 3 in acid medium and subsequent oxidation of the reaction mixture with DDQ gives, among other compounds, title compound 5 . An efficient methylation procedure of the pyridyl group in 5-(4-alkyoxyphenyl)-15-(4-pyridyl)porphyrins is described. Mixed condensation of 1 with N-methyl-4-formylpyridinium salt 9 and 3 yields among other compounds 5-(4-N-methylpyridiniumiodide)porphyrin 10 .     

Coordination properties of 4(5)-hydroxymethylimidazole and 4(5)-hydroxymethyl-5(4)-methylimidazole towards cobalt(II) ions

Two new complexes of imidazole alcohols, 4-hydroxymethylimidazole (4-CH₂OHim) and 4-hydroxymethyl-5-methylimidazole (4-CH₂OH-5-CH₃im), with cobalt(II) of formula [CoL₂(H₂O)₂](NO₃)₂ were obtained. These compounds were described through single X-ray diffraction studies, spectroscopic (Ir. Far-IR, UV-Vis-NIR) and magnetic measurements. In the present complexes imidazole ligands are bidentate coordinating the heterocyclic ring through pyridine-like nitrogen and the oxygen atom of the hydroxymethyl group (chromophore CoN₂O₄). The shape of Co(II) coordination polyhedra is that of a distorted octahedron, with the equatorial plane defined by the 4-CH₂OHim (or 4-CH₂OH-5-CH₃im) bidentate ligands and two water molecules occupying axial positions (i.e. trans to each other). Formation of successive cobalt(II) complexes with 4-CH₂OH-5-CH₃im in aqueous solution was followed quantitatively by potentiometry.     

A novel synthesis of 2-(disubstituted amino)-5(4)phenylimidazoles

The reaction of 1-phenyl-1,2-propanedione with 1,1-disubstituted guanidines in methanol yielded 2-(disubstituted amino)-4-hydroxy-4-methyl-4H-imidazoles (III). Compound III produced 5(4)methylimidazoles by catalytic hydrogenation and 5(4)chloromethylimidazoles (IV) by concentrated hydrochloric acid treatment. Solvolysis of IV in water and alcohols gave 5(4)hydroxymethyl- and 5(4)alkoxymethylimidazoles, respectively.     

Synthesis and properties of analogs of 5 (or 4)-aminoimidazole-4 (or 5)-carboxamide (AICA) and purines. 13. Synthesis of 5 (or 4)-hydrazinoimidazqles and their derivatives

A method for the synthesis of derivatives of 5 (or 4)-hydrazinoimidazole-4 (or 5)-carboxylic acid by reducing the corresponding diazoimidazoles with stannous chloride has been developed, and a number of hydrazones and semicarbazides have been synthesized. It has been shown that under the reduction conditions selected imidazo[4,5-d]-1, 2, 3-triazinone does not have cryptodiazonium properties.For Report 12, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1552–1555, November, 1983.     

Esters of (1,2, 5-trimethyl-4-hydroxy-4-piperedyl)- and phenyl-(1,2, 5-trimethyl-4-hydroxy-4-piperidyl) acetic acids

The methyl ester of a new hydroxy acid of the piperidine series (-phenyl--(1,2, 5-trimethyl-4-hydroxy 4-piperidyl)acetic acid) has been prepared. Ethyl -(1,2, 5-trimethyl-4-hydroxy-4-piperidyl)acetate has been converted into the substituted pyridine, 1,1-diphenyl-2-(2-5-dimethyl-4-pyridyl)ethylene.     

Synthesis of 2-(4-cyanophenyl)-5-(4-n-alkyl- and alkoxyphenyl) pyridines

New liquid-crystalline 2-(4-cyanophenyl)-5-(4-alkyl- and alkoxyphenyl)pyridines were obtained by condensation of 1-dimethylamino-3-dimethylimmonia-2-(4-alkyl- or alkoxyphenyl)-1-propene perchlorates with 4-cyanoacetophenone and subsequent conversion of the 1-dimethylamino-2-(p-alkyl- or alkoxyphenyl)-4-(p-cyanobenzoyl)-1,3-butadienes to 5-(4-alkyl- or alkoxyphenyl)-2-(4-cyanophenyl)pyrylium perchlorates and refluxing of the latter with ammonium acetate in acetic acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1392–1394, October, 1985.     

Transformation of 4-(1-dimethylaminoethylidene)-2-phenyl-5(4H)-oxazolone into methyl 2-benzoylamino-3-oxobutanoate. The synthesis of 1-substituted 4-benzoylamino-3-methyl-5(2H)-pyrazolones

Methyl 2-benzoylamino-3-oxobutanoate ( 3 ) was prepared from hippuric acid (1) which was converted with N,N-dimethylacetamide and phosphorus oxychloride into 4-(1-dimethylaminoethylidene)-2-phenyl-5(4H)-oxazolone ( 2 ) followed by hydrolysis with hydrochloric acid in methanol. Compound 3 was treated with hydrazines 4 to give 4-benzoylamino-3-methyl-1H-pyrazol-5(2H)-one ( 6a ) and its 1-substituted derivatives 6b-j . The corresponding hydrazones 5f, i, j were isolated as intermediates.