Heterocyclic analogs of 5,12-naphthacenequinone. 5. Synthesis of 2,3-diamino-1,4-dimethoxyanthraquinone and its heterocyclic derivatives

A new method for the synthesis of 2,3-diamino-1,4-dimethoxyanthraquinone from quinizarin has been developed. Heterocyclic analogs of 5,12-naphthacenequinone have been synthesized based on this o-diamine-4,11-dimethoxyanthra[2,3-d]imidazole-5,10-dione, 4,11-dimethoxyanthra[2,3-d][1,2,3]triazole-5,10-dione, and 5,12-dimethoxynaphtho[2,3-g]quinoxaline-6,11-dione. On the 70th Birthday of Professor E. Lukevics. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No.1, 96–102, January 2007.     

Synthesis of 2-amino-3-hydroxy- and of 2,3-diamino-3H-1,4-benzodiazepines

A new synthesis of 7-chloro-2,3-diamino-5-phenyl-3H-1,4-benzodiazepines is described, which allows for the preparation of compounds bearing the same or different substituents at the 2 and 3 positions, starting from 2-amino-7-chloro-3-hydroxy-5-phenyl-3H-1,4-benzodiazepines.     

Synthesis of 1,4-Bis(dimethylamino)-2,3-dibromo-2-butene and Its Quaternary Derivatives

Alkylation of 1,4-bis(dimethylamino)-2,3-dibromo-2-butene yielded its previously inaccessible quaternary analogs.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 5, 2005, pp. 768–770.Original Russian Text Copyright © 2005 by Saakyan, Gyul’nazaryan, Markaryan, Kocharyan, Panosyan, Karapetyan.     

The liquid phase photolysis of 1,4-dibromo-2,3-butanedione

The liquid phase photolysis of 1,4-dibromo-2,3-butanedione ((CH₂-BrCO)₂) was investigated at different wavelengths and in various solvents. In ethanol the major products are CH₃COCOCH₂Br, CH₃CH(OC₂H₅)₂, CH₃-COOC₂H₅ and CH₂BrCOOC₂H₅. Of these compounds only CH₃COCOCH₂Br is a primary photolysis product originating via hydrogen atom abstraction from CH₃CH₂OH by the excited (CH₂BrCO)₂ molecule. The CH₃CHOH radical thus formed is the probable precursor of CH₃CH(OC₂H₅)₂. It is suggested that the observed esters, which are formed in a 1:1 ratio, are produced by the photolysis of the α-oxo-hemiacetal which is formed by the reaction of (CH₂BrCO)₂ with ethanol.     

Reduction mechanism of 1,4-diamino-2,3-anthraquinone disulphonic acid

The potentiometric acid constants of 1,4-diamino-2,3-anthraquinonedisulphonic acid were calculated. The sequence of dissociation is discussed. The reduction of the reagent at a dropping mercury electrode has been investigated. The polarograms of reagent show two waves, whose adsorption and diffusion nature is respectively established. The reaction orders, together with Tafel’s slopes have been calculated.     

1,1,4,4-Tetranitrobutane-2,3-diol and its derivatives. 3. Synthesis of 1,4-dichloro- and 1,4-dibromo-1,1,4,4-tetranitrobutane-2,3-diol dinitrates and their crystalline structure

1,4-Dichloro- (1) and 1,4-dibromo-1,1,4,4-tetranitrobutane-2,3-diol dinitrates (2) were synthesized by nitration of the corresponding diols with a mixture of trifluoroacetic anhydride and nitric acid. The x-ray diffraction investigations of 1 and 2 that have been carried out showed the influence of the intramolecular interactions of the nitro and nitrate groups on the packing of the molecules in the crystal.Institute of Chemical Physics, Russian Academy of Sciences, 142432 Chernogolovka. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 3, pp. 664–671, March, 1992.     

Synthesis and structure of alkyl 2,3-dibromo-3-nitroacrylates

A synthetic approach to novel derivatives of dihalonitroethenes, methyl and ethyl 2,3-dibromo-3-nitroacrylates, was developed and their structures were investigated. X-ray single crystal analysis demonstrated that ethyl 2,3-dibromo-3-nitroacrylate had Z-configuration. The steric strain in this molecule is released mainly due to withdrawal of the ester group from the C=C double bond plane.     

Synthesis of 2,3-diaryl-1,4-diazolyl-2,3-epoxybutanes

2,3-Diaryl-1,4-diazolyl-2,3-epoxybutanes have been prepared from dimethylstilbenes. An efficient although neglected synthesis of the required olefins has been recovered from the literature. The target compounds show moderate antifungal activity.     

Synthesis of New Substituted 2,3-Dihydro-1,4-dioxin-2-ones and 1,4-Dioxan-2-ones

3-Alkyl-6-methyl-2,3-dihydro-1,4-dioxin-2-ones reacted with acetyl chloride in the presence of zinc(II) chloride to give the corresponding 3-alkyl-5-acetyl-6-methyl-2,3-dihydro-1,4-dioxin-2-ones. Oxidation of the latter with hydrogen peroxide in formic acid, followed by treatment with magnesium bromide, afforded 3-alkyl-6-methyl-1,4-dioxane-2,5-diones. Successive chlorination and dechlorination of 6-hydroxymethyl-1,4-dioxan-2-ones yielded 6-methylene-1,4-dioxan-2-ones.     

Synthesis of New Substituted 2,3-Dihydro-1,4-dioxin-2-ones and 1,4-Dioxan-2-ones

3-Alkyl-6-methyl-2,3-dihydro-1,4-dioxin-2-ones reacted with acetyl chloride in the presence of zinc(II) chloride to give 5-acetyl-3-alkyl-6-methyl-2,3-dihydro-1,4-dioxin-2-ones. Oxidation of the latter with hydrogen peroxide in formic acid, followed by treatment with magnesium bromide, afforded 3-alkyl-6-methyl-1,4-dioxane-2,5-diones. Chlorination of 6-hydroxymethyl-1,4-dioxan-2-ones with thionyl chloride and subsequent dehydrochlorination led to formation of 6-methylene-1,4-dioxan-2-ones.     

1,4-二硝基-2,3-二硝胺基哌嗪的合成

本文以乙二胺, 乙二醛和脲为原料, 通过Mannich反应, 合成出2,5,7,9-四氮杂双环[4.3.0]壬-8-酮盐酸盐(1); 化合物1 亚硝化给出2,5-二亚硝基-2,5,7,9-四氮杂双环[4.3.0]壬-8-酮(2); 硝化化合物2制得2,5,7,9-四硝基-2,5,7,9-四氮杂双环[4.3.0]壬-8-酮(3); 化合物3水解制得1,4-二硝基-2,3-二硝胺基哌嗪(4).     

Synthesis of 2-substituted-2,3- dihydro-1,4-dioxino[2,3-b]pyridine derivatives

[reaction--see text] A variety of 2-substituted-2,3-dihydro-1,4-dioxino[2,3-b]pyridines B have been synthesized from the readily available 2-nitro-3-oxiranylmethoxypyridine 1 via a Smiles rearrangement. We demonstrate how variations of reaction conditions affect the product distribution of A and B.     

Synthesis and reactions of heterocyclic methyl 2-propenoates and 2,3-epoxypropanoates with nucleophiles

Reaction of 2-(3-,4-)pyridinecarboxaldehydes 5 with carbomethoxymethylene triphenylphosphorane afforded predominantly E-methyl-3-(pyridinyl)-2-propenoates 7. Oxidation of 7a-c with m-chloroperbenzoic acid gave methyl E-3-(1-oxidopyridinyl)-2-propenoates 8a-c in high yield. The Darzen's reaction of 5a-c with methyl bromoacetate yielded a mixture of stereoisomers cis- 9a-c and methyl trans-3-(pyridinyl)-2,3-epoxy-propanoates 10a-c in a ratio of 2:1. Oxidation of cis- 9a-c and trans- 10a-c afforded the corresponding cis- 11a-c and methyl trans-3-(1-oxidopyridinyl)-2,3-epoxypropanoates 12a-c in good yield. The reaction of 11a and 12a with cyclic amines as piperidine gave the respective threo- 13 and methyl erythro-2-(1-piperidino)-3-hydroxy-3-(1-oxido-2-pyridino)propanoate 14. The sodium borohydride reduction of the N-alkoxylcarbonyl pyridinium salts of 9c and 10c afforded the corresponding N-alkoxycarbonyl-1,2-dihydropyridyl derivatives 15 and 16. A number of selected compounds ( 7a-c , 9a-c , 10a , 10c , 11a-c and 12a , 12c ) were found to be inactive in the P388 Lymphocytic screen. Compounds 9-12 did not react with the model nucleophile ethanethiol in phosphate buffer at 37°.     

Synthesis and reactions of heterocyclic 2,3-epoxypropionitriles with pyrrolidine

The Darzen's reaction of 2-(3-)pyridinecarboxaldehydes 5 with chloroacetonitrile yielded a mixture of stereoisomers cis- 6 and trans-3-(pyridinyl)-2,3-epoxypropionitriles 7 in a ratio of approximately 1:1. Oxidation of cis- 6 and trans- 7 afforded the corresponding cis- 8 and trans-3-(1-oxidopyridinyl)-2,3-epoxypropionitriles 9 in good yield. The reaction of 8a and 9a with pyrrolidine at 25° gave the respective threo- 10 and erthyro-2-(1-pyrrolidino)-3-hydroxy-3-(1-oxido-2-pyridinyl)propionitrile ( 11 ). A number of selected compounds ( 7-9a-b ) were found to be inactive in the P388 Lymphocyctic screen.     

A new reagent for determining trace selenium by gas chromatography: 1,4-dibromo-2,3-diaminonaphthalene

1,4-Dibromo-2,3-diaminonaphthalene is proposed as a reagent for conversion of selenium into a piazselenol, for determination by gas chromatography. The limit of detection is 0.03 ng of selenium.     

Synthesis of Mixed Aryl 2,3-Diarylsulphanyl-1,4-naphthoquinones

The reaction of 2-arylsulphanyl-1,4-napththoquinone with aromatic thiols and sodium dithionate leads to bis-2,3-(arylsulphanyl)naphthalene-1,4-diols in high yield. Corresponding oxidized products, namely 2,3-diarylsulphanyl-1,4-naphthoquinones, are prepared in near quantitative yield by a copper(II)-catalyzed aerial oxidation reaction of bis-2,3-(arylsulphanyl)naphthalene-1,4-diols under mild condition.     

Synthesis of new compounds containing the 2,3-dihydro[1,4]dioxino[2,3-b]pyridine heterocyclic system as a substructure

2,3-Dihydro-spiro[1,4]dioxino[2,3-b]pyridine-3,3′-pyrrolidine (8A) and 2,3-dihydro-spiro[1,4]dioxino[2,3-b]pyridine-3,4′-piperidine (9A) have been synthesized from 2-chloro-3-pyridinol. The corresponding 2,3′ (8B) and 2,4′ (9B) isomers were obtained via the Smiles rearrangement, while 9B was also selectively synthesized from 2-nitro-3-pyridinol. The separation of the isomers A and B under the sulfamide form was carried out by flash column chromatography. Subsequent transformations of the corresponding dioxinopyridine derivatives were described.     

Kinetic fluorimetric determination of iron and thallium based on oxidation transformation of 1,4-diamino-2,3-dihydroanthraquinone

Kinetic fluorimetric methods for the determination of iron(III) (0.05–0.6 ppm) and thallium(III) (0.05–0.4 ppm) are described. The fluorescent species obtained results from oxidative transformation of the reagent. The reactions are described and the experimental variables and interferences in each determination are reported.