Mononitro-β-carbolines

By the direct nitration of harmane and 1,3-dimethyl-, 1-ethyl-, 1-n-propyl-, and 1-isopropyl--carbolines with concentrated nitric acid or a mixture of nitric and acetic acids, 6- and 8-nitro-1-alkyl--carbolines have been obtained. A chromatographic method for separating the nitration products on alumina is proposed.     

Synthesis and Some Chemical Conversions of 2-([2,2]-5-Paracyclophanyl)pyrrole

2-([2,2]-5-Paracyclophanyl)pyrrole has been synthesized and nitration and formylation of it have been effected. The 1--cyanoethyl derivative and 2-formyl-5-paracyclophanyl-3H-pyrrolizine have been obtained from 5-formyl-2-([2,2]-5-paracyclophanyl)pyrrole by the action of acrylonitrile and acrolein respectively under Michael reaction conditions.     

2-Substituted imidazoles. 1. Reactions of 1-methyl-2-(2-furyl)imidazole with electrophiles

1-Methyl-2-(2-furyl)imidazole has been synthesized. Electrophilic attack (bromination, nitration, formylation, acylation, and hydroxymethylation) occurs in most cases at the free -position of the furan ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1396–1400, October, 1989.     

1-Azabicyclic compounds. 24. Selectivity of position of nitration of 1,2-dihydropyrrolizine, 5,6,7,8-tetrahydropyrrocoline and pyrrole homologs

The selectivity of the position of nitration of 1-methylpyrrole, 1,2-dimethylpyrrole, 1,2-dihydropyrrolizine, and 5,6,7,8-tetrahydropyrrocoline was found. In contrast to the selectivity of substitution during nitration of their carbocyclic analogs, o-xylene, indane and tetraline, the fraction of the -nitro-isomer in the nitration products of 1,2-dimethylpyrrole is smaller than the fraction of -nitro derivatives of 1,2-dihydropyrrolizine and 5,6,7,8-tetrahydropyrrocoline, and in the two latter cases the isomers are almost equally distributed. During nitration of the above bicyclic pyrroles, the Mills-Nixon effect does not appreciably influence the selectivity of the position of the reaction.See [1] for Communication 23.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1489–1491, November, 1987.     

Electrochemical nitration of naphthalene in the presence of nitrite ion in aqueous non-ionic surfactant solutions

The nitration of naphthalene (NapH) at a Pt electrode in aqueous NaNO₂ solutions both in the absence and presence of a non-ionic surfactant, Brij®35 (polyoxyethylene (23) dodecanol), has been studied. The electrochemical behaviour of the reactants NapH and NaNO₂ and a mixture of the two was investigated by cyclic voltammetry (CV) to determine the optimal electrolysis conditions. The peak current of NapH decreases with increasing NaNO₂ concentration, indicating that the oxidation product of the NO₂⁻ ion interacts with the NapH radical cation (NapH⁺). Controlled potential electrolysis (CPE) was carried out and the products were analysed by HPLC. The main products detected in the micellar medium were 1-nitronaphthalene, 2-nitronaphthalene, 1,2-naphthoquinone, and 1,4-naphthoquinone. In the absence of Brij 35, the naphthoquinones were produced but no nitration products were obtained. In both cases, unknown products are inferred by mass balance, which are believed to be derived from the oxidation of 1,1′-binaphthyl (BinapH) formed by NapH⁺ coupling in both micellar and aqueous media. A mechanism of nitration by the attack of NO₂ to NapH⁺ is proposed. The higher selectivity for formation of 2-nitronaphthalene in comparison to non-aqueous homogeneous media is attributed to the effect of the micellar microenvironment.     

The action of a nitrating mixture on benzo-1,5-diazepine

It has been shown that the action of a mixture of nitric and sulfuric acids on 2,4-dimethylbenzo-1, 5-diazepine leads to processes of nitration, hydrolytic cleavage, and oxidation with simultaneous isomerization, with the formation of N,N-diacetyl-4-nitro-1,2-phenylenediamines, benzotriazole, and 2-acetyl-3-methylquinoxaline.Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 8, pp. 1133–1134, August, 1970.     

Nitration of some 2-substituted thionaphthenes

A study is made of the nitration of thionaphthene-2-aldehyde, its diacetate, and of 2-(-nitrovinyl)thionaphthene. UV and IR spectroscopy show that nitration of thionaphthene-2-aldehyde in acetic anhydride gives a mixture of 3-nitrothionaphthen-2-aldehyde diacetate, 4-nitrothionaphthene-2-aldehyde diacetate, and 6-nitrothionaphthene-2-aldehyde diacetate in the ratios 106624, while nitration of thionaphthene-2-aldehyde diacetate gives a mixture of 3-nitrothionaphthene-2-aldehyde diacetate, 4-nitrothionaphthene-2-aldehyde diacetate, and 6-nitrothionaphthene-2-aldehyde diacetate in the ratios 363826. Nitration of 2-(-nitrovinyl)thionaphthene gives 4-nitro-2-(-nitrovinyl)thionaphthene.     

Electrophilic substitution reactions of acylated 2-aminoindole derivatives

The bromination, nitration, and acylation reactions of various acyl derivatives belonging to the 2-aminoindole series of compounds have been investigated. It has been found that substitution occurs both at the -carbon atom as well as at the 5- and 6-positions of the benzene ring. The ratio of reaction products depends upon the nature of the electrophile as well as on the degree of substitution of the 2-aminoindole.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 941–945, July, 1985.     

Nitration of polyhaloalkenes by mixtures of nitric and sulfuric acids

Conclusions The nitration of polyhaloalkenes was carried out under conditions for the complete conversion of nitric acid to the nitronium cation. Butyl esters of -nitrocarboxylic acids were obtained by esterification of the nitration products.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2814–2815, December, 1985.     

N,N′-dialkyl-N,N′-dinitrosulfodiamides

N,N-dinitrosulfodiamides are formed in the nitration of sulfodiamides with concentrated nitric acid or nitronium borofluoride, and also on substitutional nitration of the corresponding N,N-di-tert.-butyl derivatives with those reagents. Sulfuryl chloride reacts with the disodium salt of ethylene N,N-dinitramine to produce 2,5-dinitro-1,2,5-thiadiazolidine-1,1-dioxide. The corresponding N-nitrosulfamides are formed when nitramine salts react with methane sulfochloride.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1812–1815, August, 1989.     

Some Specific Features of Acid Nitration of 2-Substituted 4,6-Dihydroxypyrimidines. Nucleophilic Cleavage of the Nitration Products

The nitration of 2-substituted 4,6-dihydroxypyrimidines in concentrated sulfuric acid yields the corresponding 5,5-dinitro derivatives. When the substituent in position 2 is an alkyl group, the nitration occurs both at position 5 and at the -carbon atom of the side chain. Hydrolysis of 2-substituted 4,6-dihydroxy-5,5-dinitropyrimidines leads to formation of 1,1-diamino-2-R-2-nitroethylene derivatives. 1,1-Diamino-2,2-dinitro-ethylene was obtained by nitration of 4,6-dihydroxy-2-methylpyrimidine and subsequent hydrolysis of 4,6-dihydroxy-5,5-dinitro-2-(dinitromethylene)-2,5-dihydropyrimidine.     

Nitration of benzotriazole N-oxide

The nitration of benzotriazole N-oxide with dilute nitric acid gives the 7-nitro derivative, whereas nitration with a mixture of nitric and acetic acids gives isomers with nitro groups in the 5 and 7 positions in a ratio of 19.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1570–1572, November, 1976.     

Benzoxazolinones

The alkylation of the potassium and triethylammonium salts of benzoxazolinones and benzoxazolinethiones with -halo carbonyl compounds has been studied. The reaction takes place at the less electronegiative atoms of the ambident benzoxazolinone and benzoxazolinethione anions. On the nitration of 3-phenacylbenzoxazoline moiety of the molecule.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 411–415, May–June, 1987.     

Synthesis of 3, 6-anhydrocellulose by the saponification of 6-O-tosyl-2, 3-di-O-acetylcellulose

Summary 1. Derivatives of cellulose containing 3, 6-anhydro rings have been synthesized by the following route: cellulose 6-O-tritylcellulose 6-O-trityl-2, 3-di-O-acetylcellulose 2, 3-di-O-acetylcellulose 6-O-tosyl-2, 3-di-O-acetylcellulose 3, 6-anhydrocellulose.2. The composition of the 3, 6-anhydrocellulose has been studied by exhaustive acetylation, nitration, and periodate oxidation, and also by IR spectroscopy.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 6, pp. 372–375, 1966     

Determination of nitration degrees for the birch pollen allergen Bet v 1

Nitration of tyrosine residues in the major birch pollen allergen Bet v 1 may alter the allergenic potential of the protein. The kinetics and mechanism of the nitration reaction, however, have not yet been well characterized. To facilitate further investigations, an efficient method to quantify the nitration degree (ND) of small samples of Bet v 1 is required. Here, we present a suitable method of high-performance liquid chromatography coupled to a diode array detector (HPLC-DAD) that can be photometrically calibrated using the amino acids tyrosine (Tyr) and nitrotyrosine (NTyr) without the need for nitrated protein standards. The new method is efficient and in agreement with alternative methods based on hydrolysis and amino acid analysis of tetranitromethane (TNM)-nitrated Bet v 1 standards as well as samples from nitration experiments with peroxynitrite. The results confirm the applicability of the new method for the investigation of the reaction kinetics and mechanism of protein nitration.

The features of nitric acid ‘mercerization’ of cellulose

Transformation of native cellulose species into cellulose-II polymorph through the additive Knecht compound formed under the action of 68.5% nitric acid has been studied. Probable causes of peculiar temperature effects in the course of phase transformations taking place in cellulose of various origin, crystallite dispersity, or morphologic structure are discussed. The processes of hydrolytic destruction and esterification of starting materials during their mercerization by this non-traditional agent at 20 °C and 0 °C are quantitatively characterized. In the case of mercerization of wood microcrystalline cellulose at 20 °C a decrystallizing effect due to side reactions of partial nitration is noted.     

Regioselective Acylative Cleavage of Cyclic Formal of Chloramphenicol1

The amide 6 has been synthesised by reacting the amine 3 with dichloroketene in situ. This amide 6 on nitration gave formal 7, which when reacted with acetic anhydride and p-toluene sulfonic acid underwent regioselective cleavage of the dioxane ring to furnish the hemiacetal 11. This on treatment with Methanol-water-ammonia yielded chloramphenicol 2.     

Nitration of 4-methyl-5,6-dihydro-2H-pyran and some aspects of the preparation and isomerization of nitrodihydropyrans

The reaction of 4-methyl-5,6-dihydro-2H-pyran with acetyl nitrate to give additive and substitutive nitration products has been examined. It is shown that the addition product, 4-acetoxy-4-methyl-3-nitro-tetrahydropyran, is deacylated on treatment with bases to give an ,-unsaturated nitro-compound which isomerizes under the reaction conditions to a ,-unsaturated nitro-compound. 4-Acetoxy-4-nitromethyltetrahydropyran behaves similarly.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 305–308, March, 1987.     

Aryl-ONN-azoxy-α,α-dinitroalkanes and some of their derivatives

Previously unknownN-dinitroalkyl-NNO-azoxybenzenes have been prepared (by nitration ofN-(-hydroximino) alkyl-NNO-azoxybenzenes) and transformed to some derivatives.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1972–1975, November, 1994     

Synthesis of α-functional nitro compounds by the nitration of activated carbonyl compounds in a two-phase system

2-Nitro-1,3-dicarbonyl and -nitromonocarbonyl compounds were synthesized in the yields varying from moderate (30 %) to nearly quantitative by the nitration of -dicarbonyl compounds in a two-phase system: sulfuric/nitric acid mixture-chloroform at - 10÷10 °C. The use of phase transfer conditions made it possible to avoid the formation of furoxans as by-products and to simplify the isolation of products. This method is quite common for preparing various -functional nitro compounds including those containing a CF₃-group. Key words: nitration, -functional nitro compounds.Translated fromIzvestiya Akademn Nauk. Seriya Khimicheskaya, No. 1, pp. 76–79, January, 1994.