Synthesis of 6-aryl-1,3-dimethyl-6,7-dihydro-6-azalumazin-7-(6H)ones and their conversion into 2-aryl-1,2,4-triazine-3,5-(2H,4H)odiones. A new synthesis of 1-aryl-6-azauracils

Treatment of 6-amino-5-arylazo-1,3-dimethyluracils with urea or N,N′-carbonyldiimidazole gave the respective 6-aryl-1,3-dimethyl-6,7-dihydro-6-azalumazin-7-(6H)ones, which were hydrolyzed with alkali to afford 2-aryl-2,3,4,5-tetrahydro-3,5-dioxo-1,2,4-triazine-6-carboxylic acids (1-aryl-6-azauracil-5-carboxylic acids). Thermal decomposition of these carboxylic acids gave the corresponding 2-aryl-1,2,4-triazine-3,5-(2H,4H)diones (1-aryl-6-azauracils). Methylation of the latter with methyl iodide gave the corresponding 2-aryl-4-methyl-1,2,4-triazine-3,5-(2H,4H)diones (1-aryl-3-methyl-6-azauracils).     

1,2,4-三嗪类化合物的研究 VIII: 3-甲硫基-5-羟基-1,2,4-三嗪-6-羧酸乙酯和N^2-[5'-(3'-甲硫基-6'-乙氧羰基)-1',2',4'-三嗪基]-3-甲硫基-5-氧代-1,2,4-三嗪-6-羧酸乙酯的氧化及其取代反应

本文报道3-甲硫基-5-羟基-1,2,4-三嗪-6-羧酸乙酯(4)及N^2-[5'-(3'-甲硫基-6'-乙氧羰基)-1',2',4'-三嗪基]-3-甲硫基-5-氧代-1,2,4-三嗪-6-羧酸乙酯(8)分子内,甲硫基的氧化及其就地与取代芳胺进行亲核取代反应.3-甲砜基和N^2-[5'-(3'-甲硫基-6'-乙氧羰基)-1',2',4'-三嗪基]作为离去基,其离去能力相近.     

2-[2-(4,6-二甲基)-嘧啶基]-4-苯基-1,2,4-噁二唑烷-3,5-二酮的合成

异氰酸苯醇和N-[2-(4,6-二甲基)-嘧啶基]-羟胺(5)反应生成1-[2-(4,6-二甲基)-嘧啶基]-1-羟基-3-苯基脲(6)。化合物(6)在三乙胺存在下和氯甲酸乙醇反应生成2-[2-(4,6-二甲基)-嘧啶基]-4-苯基-1,2,4-噁二唑烷-3,5-二酮(1)。     

Synthesis of 4-Amino-6-phenyl-3-thioxo-2,3-dihydro-1,2,4-triazine-5(4H)-one

Russian Journal of General Chemistry -     

The dehydrogenation of the alleged hexahydro-1,2,4-triazine-3,6-dione

The dehydrogenation of the alleged hexahydro-1,2,4-triazine-3,6-dione, recently reassigned the 3-amino-2,4-imidazolidinedione structure, gives upon reaction with bromine water or sodium hypobromite bis[3-(2,4-dioxoimidazolidinyl)]diazene instead of tetrahydro-1,2,4-triazine-3,6-dione as reported previously in the literature.     

Syntheses of 4-(2-hydroperoxy-2,2-diarylethyl)-3,5-dimethylpyrazoles, 4-(2-hydroxy-2,2-diarylethyl)-3,5-dimethylpyrazoles and the related compounds

The reactions of 1,1-disubstituted ethenes with 2,4-pentanedione in the presence of manganese(III) acetate and atmospheric oxygen yielded 4-acetyl-6,6-diaryl-3-methyl-1,2-dioxan-3-ols. The latter gave 4-(2-hydroperoxy-2,2-diarylemyl)-3,5-dimethylpyrazoles by the reaction with hydrazines in methanol-acetic acid (1:1 v/v) at 50° in 15-77% yields, or 4-(2-hydroxy-2,2-diarylethyl)-3,5-dimethylpyrazoles by the reaction with hydrazines in methanol in 2-78% yields. The acid-catalyzed reaction of 4-(2-hydroperoxy-2,2-diarylethyl)-3,5-dimethylpyrazoles yielded 4-(aroylmethyl)-3,5-dimethylpyrazoles (15-55%) and 4-(2,2-diarylethenyl)-3,5-dimethylpyrazoles (9-29%).     

A novel synthesis of N(1)-(substituted)-pyrimido[5,4-e]-1,2,4-triazine-5,7(1H,6H)-diones

A new synthesis of N₁-(substituted)-pyrimido[5,4-e]-1,2,4-triazine-5,7(1H,6H)-diones, which are analogues of the natural product toxoflavin, is reported. Condensation of preformed alkyl or aryl hydrazones with 6-chloro-3-methyl-5-nitrouracil efficiently provides pyrimidotriazinediones in a three-step process that broadens the scope of R₁ substituents.     

Synthesis,Crystal Structure and Antitumor Activity of 4-(tert-butyl)-5-(1H-1,2,4-triazol-1-yl)-N-(2-hydroxy-3,5-diiodinebenzyl)-thiazol-2-amine

The title compound, 4-(tert-butyl)-5-(1H-1,2,4-triazol-1-yl)-N-(2-hydroxy-3,5-diiodinebenzyl)thiazol-2-amine, was synthesized via the reduction of 4-(tert-butyl)-5-(1H-1,2,4-triazol-1-yl)-N-benzylidene-thiazol-2-amine with Na BH4, and its crystal structure was determined by single-crystal X-ray diffraction. The compound crystallizes in monoclinic system, space group P21/c with a = 7.91944(19), b = 10.5250(3), c = 24.4985(6) , Z = 4, V = 2041.66(9) 3, Mr = 599.22, Dc = 1.949 Mg/m3, S = 1.120, μ = 3.203 mm-1, F(000) = 1152, the final R = 0.0283 and wR = 0.0592 for 3490 observed reflections(Ⅰ 2σ(Ⅰ)). X-ray analysis displays that the crystal water takes part in three intermolecular hydrogen bonds of O(2)–H(2A)···O(1), O(2)–H(2B)···N(1) and N(5)–H(5)···O(2), and an octatomic ring is formed via intramolecular hydrogen bond of O(1)–H(1A)···N(4). Furthermore, the Ⅰ···Ⅰ contacts are involved in stabilizing the overall three-dimensional network structure. The preliminary biological test shows the title compound has good antitumor activity with the IC50 value of 26 μM against the Hela cell line.     

(1S,6R)-1-羟基-6-(1,3-苯并二硫-2-氧)-3,5-环维生素D2的合成

以VD2为原料制备了1α，25－二羟基维生素D3的重要中间体（1S，6R）－1－羟基－6－（1，3－苯并二硫－2－氧）－3，5－环维生素D2。其中BDT（1，3－苯并二硫－2－氧）基团的引入有利于共轭三烯系统的保护。     

Michael reaction in synthesis of 6-amino-4-(4-butoxyphenyl)-3,5-dicyanopyridine-2(1H)-thione

The reaction of 4-butoxybenzalcyanoacetic ester with cyanothioacetamide yielded 6-amino-4-(4-butoxyphenyl)-3,5-dicyanopyridine-2(1H)-thione, also synthesized by recyclization of 2,6-diamino-4-(4-butoxyphenyl)-3,5-dicyano-4H-thiopyran and condensation of 4-butyoxybenzaldehyde with a two-fold excess of cyanothioacetamide. Substituted 2-alkylthiopyridines and thieno[2,3-b]pyridines were obtained with the indicated pyridinethione. T. G. Shevchenko Lugansk State Pedagogical Institute, Lugansk 348011. Ukraine, N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, Moscow 117913, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 213–219, February, 1998.     

A New Route to Substituted Pyrimido[5,4-e]-1,2,4-triazine-5,7(1H,6H)-diones and Facile Extension to 5,7(6H,8H) Isomers

A new route to substituted pyrimido[5,4-e]-1,2,4-triazine-5,7(1H,6H)-diones is outlined. The synthesis proceeds via pre-formed hydrazone intermediates, which are then condensed with an activated chlorouracil to build up the entire molecular framework, followed by a reductive ring closure to provide the parent series. The route has been extended to the isomeric pyrimido[5,4-e]-1,2,4-triazine-5,7(6H,8H)-dione class via the use of methylhydrazine as hydrazine surrogate, followed by regiospecific alkylation of the N(8)-H pyrimidotriazinediones with a range of alkyl and alkaryl substituents. This new methodology permits the generation of a wide range of compounds with variable substitution at the N(1), C(3), and N(8) positions for a heterocyclic scaffold with demonstrated pharmacological activity.