Synthesis of 3-amino-4-nitropyrazoles

3-Bromo-1,5-dimethyl-4-nitropyrazole does not react upon heating with aqueous ammonia, while 1,5-dimethyl-3,4-dinitropyrazole under the same conditions yields 3-amino-1,5-dimethyl-4-nitropyrazole, which is formed from 3-bromo-1,5-dimethyl-4-nitropyrazole in the presence of a copper catalyst. The amination of 1-methyl-3,4-dinitropyrazole-5-carboxylic acid is accompanied by decarboxylation, which is characteristic for 4-substituted 1-methylpyrazole-5-carboxylic acids upon heating in aqueous ammonia or water.     

Synthesis of 3-acetyl-2-amino-4-pyridone

A method hxsynthesizing 3-acetyl-2-amino-4-pyyridone has been suggested. The synthesis involves the condensation of dimethylformamide dimethylacetal at the NH₂ group of diphenylboron chelate diacetylketene aminal followed by its intramolecular cyclization under the action of NaOMe in MeOH.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 177–179. January, 1996.     

Synthesis of 3-amino-5-benzylamino-4-nitropyrazole

Conclusion A new efficient method has been developed for the synthesis of 3-amino-5-benzylamino4-nitropyrazole. The key step of this procedure is the preparation of l,l-di(alkylamino)-2nitro-2-cyanoethylenes by the condensation of nitroacetonitrile with isothiourea derivatives.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2342–2344, October, 1986.     

Synthesis and properties of 4-amino-3-cyanofurazan

Deoximation of the amidoxime of 4-aminofurazan-3-carboxylic acid and dehydration of 4-aminofurazan-3-carboxamide gave 4-amino-3-cyanofurazan. Reactions of the cyano and amino groups were studied.Latvian Institute of Organic Chemistry, Riga, LV-1006. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 693–696, May, 1994.     

3-羟基-4-氨基丁酸及其类似物的合成进展

3-羟基-4-氨基丁酸（简称GABOB）是一类有趣的氨基酸，它的一些类似物如Statine等存在于一些具有抗肿瘤、抗病毒、抗炎症等生理活性的天然产物之中。从治疗的角度讲，3-羟基-4-氨基丁酸也具有重要意义。本文简要介绍GABOB类似物的天然存在及生理活性，并从不同的起始原料出发介绍它们的立体选择性合成。     

Synthesis of substituted 2-amino-3-cyano-4-methylpyrroles

A facile route for the synthesis of substituted 2-amino-3-cyano-4-methylpyrroles from N-acetyl-α-amino ketones and malononitrile is reported.     

Synthesis of 3-nitro-4-amino- and 3,4-diaminothiocoumarins

Nitration of 4-hydroxythiocoumarin gave 3-nitro-4-hydroxythiocoumarin, which was converted to 3-nitro-4-chlorothiocoumarin by the action of phosphorus oxychloride in dimethylformamide. The corresponding 3-nitro-4-aminothiocoumarins were synthesized by reaction of 3-nitro-4-chlorothiocoumarin with ammonia or amines. The 3-nitro-4-aminothiocoumarins were hydrogenated in alcohol over Raney nickel to give 3,4-diaminothiocoumarins. The-aminovinylcarbonyl form of the 4-substituted 3-aminothiocoumarins was established on the basis of the UV, IR, and PMR spectra.See [1] for our preliminary communication.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 43–47, January, 1978.     

Synthesis of 4-hydroxy- and 3-aryl-4-amino- 2-trifluoromethylpyridines

Schemes for synthesizing 3-acyl-4-amino(hydroxy)-2-trifluoromethylpyridines from 3-acyl 4-amino-5,5,5-trifluoro-3-penten-2-ones via their diphenylboron chelate complexes have been suggested.Translated fromlzvestiyn Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2715–2718, November, 1996,     

Synthesis and crystal structure of 4-amino-3-fluorophenylboronic acid

4-Amino-3-fluorophenyl boronic acid has been synthesized from 4-bromo-2-fluoroaniline by protecting the amine group and then carrying out a lithium-bromine exchange, followed by addition of trimethyl borate and then acidic hydrolysis. We obtained a 47% yield. We also measured the X-ray crystal structure. This derivative has a relatively low boronic acid pK_a value of 7.8 when acetylated or attached to acrylamide hydrogels. It also contains a pendant amine which facilitates attachment to polymers, for example. We are using this compound to construct glucose sensing materials that operates at the physiological pH of bodily fluids.     

Synthesis of 2-amino-5-nitro-4H-pyran-3-carbonitriles

Reaction of 2-carbomethoxy-ω-nitroacetophenone with arylmethylenemalononitriles gives the previously unknown 2-amino-4-aryl-5-nitro-6-(2-carbomethoxyphenyl)-4H-pyran-3-carbonitriles. N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, Moscow 117913. E-mail: muskat@cacr.ioc.ac.ru. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1661–1663, December, 1998.     

One-pot synthesis of 3-amino-4-aryl- and 3-amino-4-hetarylfurazans

A “one pot” method for the synthesis of 3-amino-4-aryl- and 3-amino-4-hetarylfurazans from β-aryl- and 4-β-hetaryl-β-oxo acid esters was developed. Dedicated to Corresponding Member of the Russian Academy of Sciences E. P. Serebryakov on the occasion of his 70th birthday. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 1030–1032, April, 2005.     

Synthesis of 3-amino-4-(thienyl-2)furazan

3-Amino-4-(thienyl-2)furazan (3) has been synthesized from 2-acetylthiophene (4) by several routes. Nitrosation of 4, followed by oximation of the resulting oxime salt 5, gave a 6:1 mixture of the E,E and E,Z isomers of thienylglyoxime (1). Estimation of differences and analogies of these isomers' reactivity have been carried out. Oxidation and dehydration of 1 gave furoxan 11 and furazan 2, respectively. Conversion of 2, 12, 13, and 11a, b into the target amine 3 by base-promoted reaction with hydroxylamine has been reported. © 1997 John Wiley & Sons, Inc.     

Synthesis of Alkyl 5,6-Dialkyl-2-amino-3-cyanopyridine-4-carboxylates

An unusual route has been found for the hydrolysis of 3-amino-1,1-dialkoxy-6,7-dialkyl-4-aryl-3a,4,5,7a-tetrahydro-1H-pyrrolo[3,4-c]pyridine-3a,7a-dicarbonitriles in acidic medium which leads to the formation of alkyl 5,6-dialkyl-2-amino-3-cyanopyridine-4-carboxylates.     

双(3-氨基-4-羟基苯基)双酚醚类化合物的合成

以双酚化合物及对卤苯酚为起始原料,经用苄基保护、乌尔曼成醚、选择性硝化和还原脱保护4步反应,合成了具有双酚芳香醚结构的4个新型聚苯并噁唑单体：双(3-氨基-4-羟基苯基)双酚醚类化合物的盐酸盐。 确定了乌尔曼成醚反应的最佳工艺条件,证明硝化反应只发生在对卤苯酚苄保护基的邻位,改进了还原脱保护反应的成盐及后处理条件,提高了产物的质量和收率,4步反应总收率可达54.0%。 采用红外光谱、核磁共振H谱和高分辨质谱表征了每步产物的化学结构。     

Synthesis,resolution and absolute configuration of 4-amino-3-phenylpiperidine

Racemic cis-4-amino-1-benzyl-3-phenylpiperidine was prepared by reductive amination of the respective 4-piperidone via its oxime. The resolution of the racemate was accomplished by crystallization as the mandelate. The enantiomeric purity of this material was checked by NMR after derivatization to the corresponding camphorsulfonamide to be 97% ee. The absolute configuration of one enantiomer was confirmed by X-ray single crystal diffraction of the para-bromobenzenesulfonamide derivative.     

Synthesis and anticonvulsant activity of 3-amino-4(3H)-quinazolinones

Several 3-amino-4(3H)-quinazolinones were prepared from o-aminobenzoylhydrazines and triethyl orthoformate or from isatoic anhydrides, hydrazines and triethyl orthoformate. o-Aminobenzoylhydrazine intermediates were obtained by reaction of isatoic anhydrides with hydrazines. Some of the aminoquinazolinones displayed anticonvulsant activity in mice.     

Synthesis of 4-substituted 3-hydroxy-and 3-amino-6H-1,2,6-thiadiazine 1,1-dioxides

Reaction of sulfamide with ethoxymethylene derivatives yielded 4-ethoxycarbonyl-, 4-cyano-, and 4-nitro-2H,6H-1,2,6-thiadiazine 1,1-dioxide. In some cases, the corresponding open chain sulfamidomethylene derivatives were isolated. Preparation of 4-amino- and 4-amino-5-methyl-2H,6H-1,2,6-thiadiazin-3-one 1,1-dioxide is also described. Reaction of sulfamide with ethyl 3,3-ethoxypropionate afforded 3,7-bis(etlioxycarbonylmethyl)perhydro-1,5,2,4,6,8-dithiatetra-zocine 1,1,5,5-tetroxide.     

Synthesis of 5-amino-4-hetaryl-2,3-dihydro-1h-3-pyrrolones

2-Hetaryl-3-oxo-4-phthalimidobutyronitriles (and pentanonitriles) were obtained with high yields by C-acylation of hetarylacetonitriles with N-phthaloylglycine and -alanine chlorides respectively under the conditions of base catalysis. Hydrazinolysis of the phthaloyl protection in these compounds leads to the formation of 5-amino-4-hetaryl-2,3-dihydro-1H-3-pyrrolones.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1783–1790, December, 2004.