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1.
Spiro [3H-indole-3,2′-[4H] pyrido [3,2-e]-1,3-thiazine]-2,4′ (1H) diones, a class of previously unknown compound which does not form under conventional conditions, can be prepared by treatment of ‘in situ’ generated 3-indolylimine derivatives with 2-mercaptonicotinic acid under microwave irradiation in absence of any solvent or solid support in 85-92% yields in 3-8 min. The facile one pot reaction is generalized for a variety of ketones and amines to give pure pyrido [3,2-e] thiazine derivatives, which do not require further purification processes. 相似文献
2.
L. Yu. Chumakova A. M. Demchenko A. N. Krasovsky T. V. Dolishnyak M. O. Lozinskii 《Chemistry of Heterocyclic Compounds》2003,39(8):1002-1012
3-Ethoxycarbonyl-2-(N-R-thioureido)-4,5,6,7-tetrahydrobenzo[b]thiophenes were obtained by the reaction of 2-amino-3-ethoxycarbonyl-4,5,6,7-tetrahydrobenzo[b]thiophene with isothiocyanates and of 3-ethoxycarbonyl-2-isothiocyanato-4,5,6,7-tetrahydrobenzo[b]thiophene with primary and secondary amines. The cyclization paths of the products leading to derivatives of thieno[2,3-d]pyrimidine and thieno[2,3-d]-1,3-thiazine were studied. The corresponding S-substituted derivatives were obtained by the alkylation of 3-R-2-thioxo-3,4,5,6,7,8-hexahydrobenzo[b]thieno[2,3-d]pyrimidin-4-ones. 相似文献
3.
The reaction of 3-allylthio-5-phenyl-4H-1,2,4-triazole with iodine to give a mixture of 5,6-dihydro-5-iodomethyl-3-phenyl[1,3]thiazolo[2,3-c][1,2,4]triazole, 6,7-dihydro-6-iodo-3-phenyl-5H-[1,2,4]triazolo[3,4-b][1,3]thiazine, 5,6-dihydro-6-iodomethyl-2-phenyl[1,3]thiazolo[3,2-b][1,2,4]triazole, and 6,7-dihydro-6-iodo-2-phenyl-5H-[1,2,4]triazolo[5,1-b][1,3]thiazine has been studied. The structure of the products obtained was established using 1H NMR spectroscopy of their dehydriodination products. 相似文献
4.
The one-electron oxidation of toluidine blue by specific oxidising radicals such as Cl
2
−
, Tl(II), N3, Br
2
−
etc. has been studied by employing the pulse radiolysis technique. The Br
2
−
radical was found to be less efficient in oxidising toluidine blue as compared to Cl
2
−
., Tl+2 and N3. The semioxidised species exhibited only onepK
a indicating the presence of two conjugate acid-base forms whose spectral and kinetic features were evaluated. Reaction of
OH radicals with the dye gave rise to a transient species which exhibited spectral and kinetic features different from that
of the semioxidised species indicating that the mode of reaction of OH is different. 相似文献
5.
E. Karthikeyan S. Perumal S. Selvaraj 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2561-2567
A series of substituted 4,9a-diaryl-9,9a-dihydro-1H-[1,4]thiazino[4,3-a][1,3]benzimidazoles was prepared in good yields from the reaction of bis(aroylmethyl) sulfides with ortho-phenylenediamine in glacial acetic acid under reflux and under microwave irradiation. Microwave irradiation is found to accelerate the reaction, besides giving better yield in the case of the thiazinobenzimidazoles with electron-withdrawing groups in the aryl rings than the thermal reaction. 相似文献
6.
以3-芳基-5-巯基-1,2,4-三唑为原料合成了20个3-芳基-1,2,4-三唑-5-巯基乙酸乙酯(2a~e)、3-芳基-1,2,4-三唑-5-巯基乙酸(3a~e)、3-芳基-5,6-二氢噻唑并[2,3-c]均三唑(5a~e)和3-芳基-6,7-二氢均三唑并[3,4-b][1,3]噻嗪(6a~e)。研究了3a~e在微波辐射下的环化反应,合成了5个3-芳基-5-氧代-6H-噻唑[2,3-c]均三唑(4a~e)。产物经元素分析、红外、核磁共振以及质谱方法确定了结构。初步研究了代表化合物的生物活性。 相似文献
7.
Sheng-Rong Liao Yong Tang Liang Xu Xue-Feng Zhou Jun-Feng Wang Bin Yang Yong-Hong Liu 《Tetrahedron》2017,73(1):98-107
An unexpected ring-contraction from benzo[b]pyrazino[1,2-d][1,4]thiazine-1,4-diones (6) to benzo[4,5]thiazolo[3,2-a]pyrazine-1,4-diones (7) has been developed. The preliminary mechanistic studies showed the transformation contained two independent steps: the first step is the formation of a Michael adduct upon the addition of the protic solvent, in the presence of base, to the C-2-C-3 double bond of compound 6, and the second step is a ring-contraction induced by oxygen via the migration of sulfur atom from C-2 to C-3 position. And its scope is also studied. 相似文献
8.
9.
Xiao Ming JI He Ping SUN Hai Wei XU Hong Min LIU 《中国化学快报》2006,17(12):1563-1565
Thioureas have strong antifungal activities1 and their antimicrobial and insecticidal properties have been documented for more than fifty years2. Recently thiourea derivatives have been reported to possess antitubercular, antithyroid and anticancer3 prope… 相似文献
10.