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1.
Andrzej Rykowski Danuta Branowska Mieczyslaw Makosza Phan Van Ly 《Journal of heterocyclic chemistry》1996,33(6):1567-1571
An efficient procedure for the preparation of 1,2,4-triazin-5-ylcarbaldehyde oximes 2a-f from 1,2,4-triazines 1a-f and nitromethide ion is described. The oximes 2c-d were converted into corresponding 5-cyano-1,2,4-triazines 6c-d . The latter compounds react easily with various nucleophiles to afford 5-substituted 1,2,4-triazines 7a-i and with 1-pyrrolidino-1-cyclohexene to form cyano derivative of 5,6,7,8-tetrahydroisoquinoline 9 . 相似文献
2.
3.
Kozhevnikov D. N. Kataeva N. N. Rusinov V. L. Chupakhin O. N. 《Russian Chemical Bulletin》2004,53(6):1295-1300
A simple procedure was developed for the synthesis of 1,2,4-triazines and their 4-oxides containing the ClCH2, Cl2CH, or CCl3 group at position 3 by cyclization of 2-aryl-2-hydrazono-1-oximinoethanes with the corresponding chloroacetonitriles. The reaction pathway depends on the number of halogen atoms in the acetonitrile used. The reactions with trichloroacetonitrile, monochloroacetonitrile, and dichloroacetonitrile afford 3-trichloromethyl-1,2,4-triazines, 3-chloromethyl-1,2,4-triazine 4-oxides, and a mixture of the corresponding dichloromethyltriazines and their 4-oxides, respectively. The reactions of 3-trichloromethyl-1,2,4-triazines with indoles and phenols are accompanied by tele-substitution with elimination of halogen from the trichloromethyl group to give 5-indolyl- (or 5-hydroxyphenyl)-3-dichloromethyl-1,2,4-triazines. 相似文献
4.
The reaction of acidhydrazides with α-substituted carbonyl compounds in the presence of metal acetates gives substituted 1,2,4-triazines. These cyclisations could be effected without any added acetate by refluxing in dimethyl formamide, pyridine/acetic acid or dimethyl sulfoxide Sixty five 3,5,6-tri-3,6-di and 6 monosubstituted-1,2,4-triazines (in 50–90% yields) with a wide variation in the C3 substituent (alkyl, aryl or heteryl) and the C6-substituent (aryl or heteryl) are reported. The mechanistic path followed in the formation of these compounds is discussed. 相似文献
5.
S. G. Alekseev P. A. Torgashev M. A. Fedotov A. I. Rezvukhin S. V. Shorshnev A. V. Belik V. N. Charushin O. N. Chupakhin 《Chemistry of Heterocyclic Compounds》1988,24(4):434-441
The electron structures of 3-substituted 1,2,4-triazines and isomeric N-methyltriazinium salts were calculated by the CNDO/2 method. The results of the calculations were compared with the parameters of the 13C, 15N, and 14N NMR spectra, as well as with experimental data on the protonation, N-alkylation, and reactions of 1,2,4-triazines with simple nucleophiles. The protonation centers of 1,2,4-triazines were determined by means of 1H, 13C, and 14N NMR spectroscopy. The covalent adducts formed by the proton salts of 3-methoxy-, 3-methylthio-, 3-morpholino-, and 3-pyrrolidino-1,2,4-triazine with water and methanol were recorded by 1H NMR spectroscopy.Communication 7: O. N. Chupakhin, V. N. Chaurushin, I. V. Kazantseva, M. G. Poinzovskii, E. O. Sidorov, P. A. Torgashev, and A. V. Belik, Khim. Geterotsikl. Soedin., No. 10, 1385 (1987).Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 525–533, April, 1988. 相似文献
6.
Kozhevnikov D. N. Kozhevnikov V. N. Kovalev I. S. Rusinov V. L. Chupakhin O. N. Aleksandrov G. G. 《Russian Journal of Organic Chemistry》2002,38(5):744-750
The scope of functionalization of 1,2,4-triazines can be considerably extended via successive nucleophilic substitution of hydrogen (SN
H) and ipso-substitution. A convenient procedure has been developed for direct cyanation of 1,2,4-triazine 4-oxides with acetone cyanohydrin in the presence of triethylamine. The cyano group in the resulting 5-cyano-1,2,4-triazines is readily replaced by reactions with various aliphatic alcohols and amines. 相似文献
7.
Jim Clark 《Journal of mass spectrometry : JMS》1972,6(5):467-473
Fragmentation of 7-substituted 5-trifluoromethylpyrimido(5,4-e)as-triazines is dominated by consecutive losses of N2 and HCN from the triazine ring. Deuterium labelling, accurate mass measurements and spectral changes with substitution patterns confirm the fragmentation pathways. Comparison of the spectra with those of corresponding pteridines indicates that the 1,2,4-triazine ring fragments much more readily than the pyrazine ring. 相似文献
8.
Intermolecular inverse electron demand cycloadditions of 2-substituted imidazoles with various 1,2,4-triazines produced both imidazo[4,5-c]pyridines (3-deazapurines) and pyrido[3,2-d]pyrimid-4-ones (8-deazapteridines). The product distribution was controlled by reactant substituents and influenced by reaction temperature. A regioselective method for the preparation of 6-unsubstituted 1,2,4-triazines was also developed. By using this route to 8-deazapteridines, a new 8-deazafolate analogue was prepared. 相似文献
9.
3-甲硫基-5-氧代-2.5-二氧-1,2,4-三嗪(Ic)与取代的苯磺铣氯反应,在无水吡啶中生成N-[6-(3-甲硫基-5-负氧基)-1,2,4-三嗪基]吡啶内嗡盐(4);在NaOH-H~2O-Ch~3COCH~3中生成3-甲硫基-4-(取代苯磺铣基)-5-氧化-6-羟基-1,4,5,6-四氢- 12,4-(6);资Naoh-Ch~3O中则生成1-(对甲苯磺铣基)-3-甲硫基-6-甲氧基-1,4,5,6-四氢-三嗪(7)显示了其6-C具有不寻常的亲电特性. 相似文献
10.
P. S. Lobanov L. A. Sarafanova A. A. Potekhin 《Chemistry of Heterocyclic Compounds》1991,27(10):1120-1124
Alkylidene derivatives of 2-aminoethylhydrazines exist in solutions either as 2-aminoethylhydrazones or as the ring-chain tautomeric mixtures of the hydrazone—perhydro-1,2,4-triazine depending on the structure. The oxidation of perhydro-1,2,4-triazines leads to the formation of 2,3,4,5-tetrahydro-1,2,4-triazines.For Communication 21, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1392–1396, October, 1991. 相似文献
11.
V. L. Rusinov E. N. Ulomskii O. N. Chupakhin A. Yu. Petrov E. A. Sharonov 《Chemistry of Heterocyclic Compounds》1989,25(2):209-213
The reaction of 6-nitro-7-oxo-4,7-dihydroazolo[5,1-c]-1,2,4-triazines with O-, N-, and S-nucleophiles leads to the corresponding 6-substituted compounds. In the reaction of 2,4-dimethyl-6-nitro-7-oxo-4,7-dihydro-1,2,4-triazolo[5,1-c][1,2,4]triazine with hydrazine hydrate, 3-methyl-5-(N-methylamino)-1,2,4-triazole is formed.Article 8, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 253–257, February, 1989. 相似文献
12.
A tethered imine-enamine methodology has been developed for the direct conversion of 1,2,4-triazines into highly substituted pyridines via the inverse electron demand Diels-Alder reaction which avoids the need for a discrete aromatisation step. This TIE methodology has also been applied in one pot reaction cascades involving 1,2,4-triazines and utilising MnO(2)-mediated tandem oxidation processes (TOPs). 相似文献
13.
3-Hydroxy- (I),3-mercapto- (II), and 3-amino-5-(2-furyl)-1,2,4-triazines (III) are prepared by cyclizing respectively the semicarbazone, thiosemicarbazone, and guanidylhydrazone of 2-furylglyoxal. Treatment of III with nitrous acid converts it to I. Iodine oxidizes II to the disulfide. Depending on the reaction conditions,2-furylglyoxal hydrate and aminoguanidine, give 5- and also 6-(2-furyl)-substituted 3-amino-1,2,4-triazines. Under the same conditions the undehydrated furylglyoxal and aminoguanidine give only the 5-(2-furyl) derivative. Hydrochlorides and N-acetyl derivatives of the two amines are prepared.For Part X see [1]. 相似文献
14.
A general synthesis of 1,2,4-triazines, from 3-methylthiotriazines is described. It has been shown that 1,2,4-triazines undergo covalent hydration across the N4-C5 bond. 相似文献
15.
Andrzej Rykowski Eliza Guzik Mieczyslaw Makosza Wolfgang Holzer 《Journal of heterocyclic chemistry》1993,30(2):413-418
The configuration of (3-substituted)-1,2,4-triazin-5-ylcarbaldoximes and (3-substituted)alkyl-1,2,4-triazin-5-ylketoximes was determined by means of 1H-nmr, 13C-nmr, 15N-nmr and homonuclear NOE-difference spec-troscopy. Oximes resulting from reaction of 1,2,4-triazines with nitroalkanes were found to be either pure E-isomers or E/Z-mixtures with the amount of E-isomer greatly predominating. Detailed 13C-nmr data of the oximes investigated are presented. 相似文献
16.
Shoji Asano Keiji Itano Kohfuku Kohda Yuriko Yamagata 《Journal of heterocyclic chemistry》1996,33(4):1115-1121
Reaction of 9-substituted (methyl or benzyl) 1-aminoadenines 1 with hydrazine afforded 9-substituted 6-hydrazinopurines 2 and 1-substituted 5-ammo-4-(4-amino-1,2,4-triazol-3-yl)imidazole ( 4 ). The product ratio of 2 to 4 rose with increasing amounts of methanol used as the solvent. When the same reaction was carried out using 1,9-dimethyladenine instead of 1 , compounds 2 and 4 were also obtained with N6,9-dimethyladenine. A possible mechanism for formation of 2 and 4 is discussed. 相似文献
17.
Ronald I. Trust J. Donald Albright F. M. Lovell N. A. Perkinson 《Journal of heterocyclic chemistry》1979,16(7):1393-1403
Synthetic methods for the preparation of 6-aryl-1,2,4-triazolo[4,3-b]-1,2,4-triazines ( 1 ) and the 7-aryl isomers ( 2 ) are described. Compounds 1 were prepared from aryl glyoxaldoximes 76 via 6-aryl-1,2,4-triazin-3(2H)ones ( 75 ). A simple procedure for the preparation of the 7-aryl isomers was effected using arylglyoxals 11 and the triazoles ( 4, 12a and 12b ). However, complete regioselectivity was not realized in all cases, especially when the triazoles were substituted at the C-5 position. A regiospecific synthesis of the 7-aryl isomers 2 was developed via the 3-methylthio-5-aryl-1,2,4-triazines ( 61 ). The structure of the parent 6-phenyl derivative 5 was confirmed by x-ray crystallography. 相似文献
18.
We have studied isomerization of 6-substituted 5-hydroxy-3-propargylthio-1,2,4-triazines using base catalysis. We have used
NMR correlation spectroscopy (1H/15N HMBC spectra) to prove the structure of the regioisomer formed. The type of regioisomer formed (3,6-dimethylthiazolo[3,2-b]-1,2,4-triazin-7-one)
allows us to say that isomerization occurs as a direct propynyl rearrangement.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 453–457, March, 2006. 相似文献
19.
Yoshihisa Kurasawa Mari Okiyama Yumiko Kamigaki Megumi Kanoh Atsushi Takada Yoshihisa Okamoto 《Journal of heterocyclic chemistry》1988,25(4):1259-1262
The reactions of the 3-substituted 4-amino-8-ethoxycarbonyl[5,1-c][1,2,4]triazines 1 and 2 with o-amino-phenol hydrochloride gave the pyrazolo[1′,5′:3,4][1,2,4]triazino[5,6-b][1,5]benzoxazepines 5 and 8 . The alkylation of 5 with methyl iodide and isopropyl iodide afforded the 6-alkoxylpyrazolo[1′,5′:3,4][1,2,4]triazino-[5,6-b][1,5]benzoxazepines 6a and 6b , respectively. Refluxing of 5, 6a, 6b and 8 in hydrochloric acid/acetic acid resulted in ring transformation to produce the spiro[benzoxazole-2′(3′H),4(1H)pyrazolo[5,1-c][1,2,4]-triazines] 7a, 7b and 9 . The screening data of the above compounds was described. 相似文献
20.
Abdollah Rahimi Davood Habibi Amin Rostami Mohammad Ali Zolfigol Shadpour Mallakpour 《Tetrahedron letters》2018,59(4):383-387
The direct aerobic oxidation of 4-substituted urazoles using the laccase enzyme from Trametes versicolor in a phosphate buffer solution at ambient temperature, and subsequent cross-coupling with sodium benzenesulfinates was investigated to afford arylsulfonyl-1,2,4-triazolidine-3,5-dione derivatives in good to high yields. 相似文献