4-Aminofurazan-3-carboxylic Acid Iminoester in Reactions with N,O-Nucleophiles

Reactions of 4-aminofurazan-3-carboxylic acid iminoester with o-aminophenol and ethylenediamine give rise respectively to 4-(1,3-benzoxazol-2-yl)- and 1-(4,5-dihydro-1H-imidazol-2-yl)-1,2,5-oxadiazol-3-amines, with aminoethanol arises 2-[(Z)-1-amino-1-(4-amino-1,2,5-oxadiazol-3-yl)methylideneamino]-1-ethanol. Treating of 3-amino-4-(1H-benzo[d]imidazol-2-yl)-1,2,5-oxadiazole with triethyl orthoformate in acetic anhydride yielded benzo[4,5]imidazo[1,2-c][1,2,5]oxadiazolo[3,4-e]pyrimidine, and alkylation with haloalkanes furnished 3-amino-4-(1-R-benzo[d]imidazol-2-yl)-1,2,5-oxadiazoles.     

3-氨基-4-氧代氰基呋咱捕获与表征

3,4-双(4-氨基呋咱-3-基)氧化呋咱由活性中间体3-氨基-4-氧代氰基呋咱分子间发生二聚获得,但3-氨基-4-氧代氰基呋咱不稳定,无法通过分离、纯化及光谱鉴定证实其存在.采用4种不同的烯烃与3-氨基-4-氧代氰基呋咱发生1,3-偶极环加成反应得到3-(4-氨基呋咱-3-基)-5-氰基-Δ2-异噁唑啉、3-(4-氨基呋咱-3-基)-5-乙酰氧基-Δ2-异噁唑啉、3-(4-氨基呋咱-3-基)-5-正丁基-Δ2-异噁唑啉及3-(4-氨基呋咱-3-基)-环己烷并-Δ2-异噁唑啉4种Δ2-异噁唑啉衍生物;采用苯甲酰氯为捕获剂,与3-氨基-4-氧代氰基呋咱反应获得了3-氨基-4-(N-苯甲酸基氨基羰基)呋咱化合物;通过红外光谱、核磁共振光谱、质谱、元素分析表征了5种新化合物的结构,提供了活性中间体3-氨基-4-氧代氰基呋咱存在的间接证据.     

Bis(4″-nitro-[3,3’:4’,3″]terfurazan-4-yl)diazene as a new energetic compound

Russian Chemical Bulletin - 3,4-Bis(4-aminofurazan-3-yl)furazan was used to obtain a new energetic terfurazan derivative, namely,...     

Oxidation of heterocyclic nitrogen Ylids to nitro heterocycles. Comparison of a sulfilimine and a phosphine imine

Oxidation of 3-amino-4-(4-chlorophenyl)furazan ( 1 ) with peroxytrifluoroacetic acid (ptfa) gave azoxy(4-chlorophenylfurazan) ( 6 ) as the major product along with a small amount of 3-(4-chlorophenyl)-4-nitrofurazan ( 5 ). The dimethylsulfilimine 2 derived from 1 gave near quantitative yields of 5 when subjected to oxidation with either ptfa or m-chloroperoxybenzoic acid (mcpba). In contrast, both the trioctylphosphine imine 3 and the triphenylphosphine imine 4 derived from 1 were oxidized by mcpba to give 6 as the exclusive product.     

Die Acylierung von 5-Amino-1 H-1, 2, 4-triazolen. Eine 13C-NMR.-Studie

The Acylation of 5-Amino-1 H-1,2,4-triazoles. A ¹³C-NMR. Study The acylation of 3-substituted-5-amino-1 H-1,2,4-triazoles (1) with methyl chloroformate or dimethylcarbamoyl chloride yielded mainly 1-acyl-5-amino-1,2,4-triazoles ( 2 and 3 ). Acylation of 3-methyl-, 3-methoxy- and 3-methylthio-5-amino-1 H-1,2,4-triazole ( 1b , 1c and 1d ) with methyl chloroformate gave up to 10% of the 1-acyl-3-amino-1,2,4-triazoles. For the unsubstituted 5-amino-1,2,4-triazole (1a) , a (1:1)-mixture of the 3- and 5-isomers 2a and 4 was obtained in dioxane in the presence of triethylamine. No 4-acylated product was detected in contrast to earlier reports. The structures of the reaction products were determined with the aid of proton coupled ¹³C-NMR. spectra using the corresponding N-methyl-1,2,4-triazoles as reference compounds.     

5,7-Dimethyl-3-phenylfurazano- and -furoxano[5,4-a]pyrimidinium perchlorates: New types of condensed systems

5,7-Dimethyl-3-phenylfuroxano[5,4-a]pyrimidiniumperchlorate (II) was obtained by the reaction of 4-amino-3-phenylfuroxan with acetylacetone in the presence of HClO₄. The structures of II and its furazan analog I were proved by x-ray diffraction analysis, and their ¹³C NMR spectra were studied. The cations of I and II (which contain a conjugated condensed system with delocalization of the positive charge) and their monocyclic analogs — phenylfarazan, 3-phenylfuroxan, and 4,6-dimethylpyrimidine — were subjected to quantum-chemical calculation by the CNDO/2 method.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 233–238, February, 1992.     

Arylierungen von cyclischen Guanidin-Analogen mit α-halogenierten Anthrachinonen: neue Anthrapyrimidine

Arylation Reaction of Cyclic Guanidine-Analogs with α-Halo- anthraquinones: New Anthrapyrimidines 2-Amino-benzimidazole gives on Ullmann-reaction with α-halo-athraquinones such as 1-amino-4-bromoanthraquinone-2-sulfonic acid (la) the new benzimidazo-anthrapyrimidine 2a , whereas 3-amino- triazole gives under the same conditions two products: the 1,2,4-triazoloanthrapyrimidine 7 and l-amino-4-(3-amino-1,2,4- triazolyl)anthraquinone-2-sulfonic acid ( 8 ). The new structures were elucidated by ¹H- and ¹³C-NMR. and X-ray analysis.     

Synthesis of certain 1,2,4-triazole nucleoside derivatives

The syntheses of 3-amino-4-methyl-1-(β-D-ribofuranosyl)-1,2,4-triazolin-5-one ( 8a ) and its 2′-deoxy analog 8b as well as 5-amino-2-methyl-1-(β-D-ribofuranosyl)-1,2,4-triazolin-3-one ( 12 ) have been accomplished. Compounds 8a and 8b were synthesized via glycosylation of 3-bromo-5-nitro-1,2,4-triazole which was followed by replacement in three steps of the 3-bromo function to yield 3-nitro-1-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)-1,2,4-triazolin-5-one ( 4a ) and its 2′-deoxy analog 4b . Compounds 4a and 4b were methylated at N², hydrogenated and deblocked to give 3-amino-4-methyl-1-(β-D-ribofuranosyl)-1,2,4-triazolin-5-one ( 8a ) and the 2′-deoxy analog 8b . Compound 12 was synthesized by glycosylation of 3-amino-1-methyl-1,2,4-triazolin-5(2H)-one ( 10 ). The structures of 8b and 12 were confirmed by single crystal X-ray diffraction analysis.     

Amination of 4-nitro- and 4-cyanopyridazines by liquid ammonia/potassium permanganate

4-Nitro-3- R ¹-6- R ²-pyridazines ( 1 ) ( a, R ¹ = R ² = 2-pyridyl; b, R ¹ = H, R ² = phenyl; e, R ¹ = H, R ² = p-methoxyphenyl; d, R ¹ = R ² = H ) are aminated by liquid ammonia/potassium permanganate to the corresponding 5-amino-4-nitropyridazines 3a-d. The 4-cyano-3-R¹-6-R²-pyridazines 4a,b are only aminated in the presence of potassium amide in liquid ammonia/potassium permanganate to give the 5-amino-4-cyanopyridazines 6a,b. The 5-amino-4-nitropyridazines 3a,b,d are converted to the 4,5-diaminopyridazines 7a,b,d by reduction over a Pd/C catalyst. Reaction of 7b with glyoxal leads to 5-phenylpyrazino[2,3-d]pyridazine ( 8b ).     

Synthesis of 4-isobutyl substituted thiophenes byGewald reaction

Summary TheGewald reaction of 4-methyl-2-pentanone with alkyl cyanoacetates was investigated. Alkyl 2-amino-4-isobutylthiophene-3-carboxylates (4) were formed, together withbis-(2-amino-3-alkoxycarbonyl-4-isobutyl-5-thienyl)-disulfides (5) and alkyl 2-amino-4-isobutyl-5-morpholinothiophene-3-carboxylates (6). The absence of any 4-methyl substituted aminothiophene in the product mixtures came up highly unexpected. The mechanism of the reaction is discussed with respect to previously reported suggestions.Dedicated to Professor Dr.Karl Gewald on the occasion of his 65^th birthday     

Recyclization of 5-Amino- oxazoles as a Route to new Functionalized Heterocycles (Developments of V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry of the NAS of Ukraine)

The recyclizations of 5-amino- and 5-hydrazine-1,3-oxazoles mainly with electron-withdrawing group in 4^th position are considered. The chemical behavior of these heterocycles is due to the presence of two hidden amide fragments; therefore, the recyclization processes include a stage of nucleophile attack on 2^nd or 5^th position of the oxazole cycle. When the nitrile group is present in 4^th position, it is often involved in the recyclization forming α-aminoazoles. 5-Amino/hydrazine-1,3-oxazoles undergo recyclization both in nucleophilic (amines, hydrazine, thionating agents) and electrophilic medium ((trifluoro)acetic acid, other acylating agents). The numerous types of functionalized heterocycles can be easily obtained with the usage of these recyclizations, such as the derivatives of 3-amino-6,7-dihydro-5H-pyrrolo[1,2–a]imidazole, imidazolidine-2,4-dione, 1H-pyrazole-3,4,5-triamine, 5,6-diamino-2,3-diphenylpyrimidin-4(3H)-one, 2-(2-R-7-oxo-5-(trifluoromethyl)oxazolo[5,4–d]pyrimidin-6(7H)-yl)acetic acid, 2-R-4-(5-R′-1,3,4-oxadiazol-2-yl)oxazol-5-amine, (amino(5-amino-1,3,4-thiadiazol-2-yl)methyl)phosphonate.     

Synthesis of 4-acetyl-5(3)-amino-3(5)-methylpyrazoles and pyrazolo[3,4-d]pyrimidines from diacetylketeneN,S-acetal

Isomeric 4-acetyl-5-amino-3-methyl- and 4-acetyl-3-amino-5-methylpyrazoles (2, 3) were formed in the reaction of hydrazines with 3-[amino(methylthio)methylene]pentan-2,4-dione (1) (diacetylketeneN,S-acetal). Pyrazolo[3,4-d]pyrimidines (5a,b) were synthesized by condensation of 4-acetyl-5-amino-1,3-dimethylpyrazole (2a) with amide dimethylacetals followed by treatment with ammonium acetate. The structures of the compounds obtained were confirmed by¹³C and¹⁵N NMR spectroscopy.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1429–1433, August, 1993.     

2-(2-氨基-3-吡啶基)-苯并咪唑的合成、晶体结构和荧光特性研究

在合成2-(2-氨基-3-吡啶基)-苯并咪唑的基础上,利用NMR(1H、13C、COSY、HSQC和HMBC)、MS、IR和UV进行了详细表征;通过X-ray单晶衍射仪测定了该化合物的晶体结构,实验结果表明该晶体属于三方晶系(空间群R3,a=1.833 7(3)nm,b=1.833 7(2)nm,c=1.777 7(4)nm,V=5.176 4(15)nm3,Z=18),很好地支持了波谱表征的结果。同时,结合密度泛函计算,研究了2-(2-氨基-3-吡啶基)-苯并咪唑的荧光光谱。结果表明,化合物的双荧光不是由同一种异构体发射的,而是来源于不同异构体:长波区500~600 nm的荧光由K构型发射,短波区350~450 nm的发射由异构体E1和E2共同产生,理论预测的光谱与实验一致。     

Synthesis of nitro,nitroso, azo,and azido derivatives of (4-R<Superscript>1</Superscript>-5-R<Superscript>2</Superscript>-1,2,3-triazol-1-yl)-1,2,5-oxadiazoles by oxidation and diazotization of the corresponding amines

Nitro-, nitroso-, and azo-1,2,5-oxadiazoles with 4-R¹-5-R²-1,2,3-triazol-1-yl substituents were synthesized by oxidation of amino-(1,2,3-triazol-1-yl)-1,2,5-oxadiazoles (aminotriazolylfurazans). Azido-1,2,5-oxadiazole was prepared by diazotization of amino(triazolyl)furazan followed by treatment of the diazonium salt with sodium azide. Depending on the nature of the substituents and the reagent, triazolylfurazans can undergo destruction to give amino-R-furazans (R = NO₂, N₃, aminofurazanylazo), the amino group being formed from the triazole ring. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1859–1865, August, 2005.     

A New Convergent Synthesis of Thiamine Hydrochloride

Thiamine hydrochloride ( 1a ; 3-[(4-amino-2-methylpyrimidin-5-yl)methyl]-5-(2-hydroxyethyl)-4-methylthia-zolium chloride hydrochloride; vitamin B¹) has been synthesized in excellent yield by condensation of 3-mercapto-4-oxopentyl acetate (5a) with 3, 4-dihydro-7-methylpyrimido[4, 5-d]pyrimidine (4) in formic acid. The two intermediates 5a and 4 are prepared from 3-chloro-4-oxopentyl acetate (3) and 4-amino-2-methyl-5-(aminomethyl)-pyrimidine (Grewe diamine; 2a ), respectively.     

Photoreaction of pyrido[2,3-c]furoxan

When pyrido[2,3-c]furoxan 4 was irradiated in acetonitrile containing a little water with a low pressure mercury lamp, 3-nitro-2-pyridone 5 was obtained. When compound 4 was irradiated in the presence of morpholine with a low pressure mercury lamp in an argon atmosphere, 6-morpholinopyridine 2,3-dioxime 6 , 6-morpholinopyrido[2,3-c]furazan 7 , 3-amino-6-morpholino-2-nitropyridine 8 , and 3-amino-4,6-dimorpholino-2-nitropyridine 9 was produced. The results of photoreaction study indicated the only photo-product to be compound 6 . The main difference between these two reactions may be considered due to the behavior of nitrogen in the pyridine ring.     

Über die Dicyanierung der 1,4-Diaminoanthrachinone und die Reaktivität der 1,4-Diamino-9,10-dihydroanthracen-2,3-dicarbonitrile gegenüber nucleophilen Reagenzien 3. Mitteilung über Arylierungen und Heterocyclisierungen von Anthrachinonsystemen

The Dicyanation of 1,4-Diaminoanthraquinones and the Reactivity of 1,4-Diamino-9,10-dioxo-9,10-dihydroanthracene-2,3-dicarbonitriles towards Nucleophilic Reagents The reaction of 1-amino-9, 10-dioxo-4-phenylamino-9,10-dihydroanthracene-2-sulfonic acid ( 1 , R?C₆H₅) with cyanide in water yields a mixture of 1-amino-9,10-dioxo-4-phenylamino-9,10-dihydroanthracene-2-carbonitrile ( 3 , R ? C₆H₅) and 1-amino-4-(phenylamino)anthraquinone ( 4 , R ? C₆H₅) under the usual reaction conditions (Scheme 1). In dimethylsulfoxide, however, a second cyano group is introduced, and 1-amino-9,10-dioxo-4-phenylamino-9,10-dihydroanthracene-2,3-dicarbonitrile (7) is formed (Scheme 2). The cyano groups are very reactive towards nucleophiles. The cyano group in 2-position can be substituted by hydroxide and aliphatic amines (Schemes 5 and 6). The cyano group in 3-position can be eliminated by aliphatic amines and hydrazine (Scheme 7). Nucleophilic attack at the cyano C-atom of the 2-cyano group by suitable reagents leads to ring formation, yielding e.g. 2-(Δ²-1, 3-oxazolin-2-yl)-, 2-(benz[d]imidazol-2-yl)- and 2-(1H-tetrazol-5-yl)anthraquinones (Schemes 8 and 10).     

Cyclocondensation of N-aryl-3-oxobutanethioamides with 5-amino-3-R-4-R1-pyrazoles

The cyclocondensation products of N-aryl-3-oxobutanethioamides with 5-amino-3-R-4-R¹-pyrazoles are 4-(arylamino)-2-methyl-7-R-8-R¹-pyrazolo[1,5-a]pyrimidine and pyrazolo[1,5-a]pyrimidine-4-thione derivatives, the ratio of which depends on the nucleophilicity of the starting 5-amino-3-R-4-R¹-pyrazoles and the presence of a proton donor solvent. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1550-1555, October, 2008.     

New heterocyclic furazano[3,4-d ][1,2,3]triazine system as a platform for energetic compound engineering

Novel 7-azidofurazano[3,4-d ][1-3]triazine 5-oxide was synthesized from 3-amino-4-(tetrazol-5-yl)furazan and nitronium salt. Its characterization including energetic properties is described.     

The mannich reaction in the synthesis of N,S-containing heterocycles 4. Aminomethylation of 6-amino-3,5-dicyano-1,4-dihydropyridine-2-thiolates: A convenient regioselective route to 3,5,7,11-tetraazatricyclo[7.3.1.02,7]tridec-2-ene derivatives

Treatment of N-methylmorpholinium 4-R-6-amino-3,5-dicyano-1,4-dihydropyridine-2-thiolates (R = 2-ClC₆H₄ and 2-MeOC₆H₄) with primary amines in the presence of an excess of formaldehyde gave 13-R-8-thioxo-3,5,7,11-tetraazatricyclo[7.3.1.0^2,7]tridec-2-ene-1,9-dicarbonitrile derivatives in high yields (66–95%). In a similar way, aminomethylation of 3-R-10-amino-7,11-dicyano-9-aza-3-azoniaspiro[5.5]undeca-7,10-diene-8-thiolates (R = Me and Et) afforded 1′-alkyl-8-thioxospiro[3,5,7,11-tetraazatricyclo[7.3.1.0^2,7]tridec-2-ene-13,4′-piperidine]-1,9-dicarbonitriles in 43–91% yields. Alternatively, these compounds were obtained by multicomponent cyclocondensation of N-alkylpiperidin-4-ones, cyanothioacetamide, primary amines, and aqueous formaldehyde. The starting 3-R-10-amino-7,11-dicyano-9-aza-3-azoniaspiro[5.5]undeca-7,10-diene-8-thiolates were prepared by a new method from N-alkylpiperidin-4-ones and cyanothioacetamide. The structure of 5,11-bis(4-ethoxyphenyl)-13-(2-methoxyphenyl)-8-thioxo-3,5,7,11-tetraazatricyclo[7.3.1.0^2,7]tridec-2-ene-1,9-dicarbonitrile was examined by X-ray diffraction analysis. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1014–1022, May, 2007.