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1.
Y. C. Tong 《Journal of heterocyclic chemistry》1975,12(3):451-453
1,2,5-Thiadiazolo[3,4-b]pyrazine and its derivatives were prepared. Nucleophilic displacements of halogen atoms on the nucleus were reported. 相似文献
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3.
Augusto Colombo Jordi Frigola Juan Parés Blas Andaluz 《Journal of heterocyclic chemistry》1989,26(4):949-955
The synthesis and structure elucidation of new pyrazolo[3,4-b][1,4]diazepines and pyrazolo[3,4-b]pyrazines are reported and the characterisation of isomers and tautomers by proton and carbon-13 nmr are discussed. In some case only NOE experiments allow us to identify the isomeric structure. 相似文献
4.
I. B. Starchenkov V. G. Andrianov A. F. Mishnev 《Chemistry of Heterocyclic Compounds》1999,35(4):499-508
The reactions of 5,6-diamino- and 5,6-dihydrazinofurazano[3,4-b][yrazine that produce polycyclic or highly reactive compounds
are reviewed. The furazan ring has a deactivating effect on the amine functions of these compounds.
Dedicated to Professor Henk van der Plas on his 70th birthday.
For No. 6, see [1].
Latvian Institute of Organic Synthesis, Riga LV-1006
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 564–573, April, 1999. 相似文献
5.
The condensation of 4-amino-2,1,3-benzothiadiazole (IV) with diphenyliodonium-2-earboxylate gave N-(2,1,3-benzothiadiazoI-4-yl)anthranilic acid (V) (28%), which was cyclized with phosphorus oxychloride to 6-chloro[1,2,5]thiadiazolo[3,4-c]acridine (VI) (84%). Treatment of VI with 3-(dimethylamino)-1-propanethiol hydrochloride in phenol afforded 6-[ [3-(dimethylamino)-propyl]thio] [1,2,5]thiadiazolo[3,4-c]acridine (VII) (65%). The reaction of IV with a mixture of methyl and ethyl 2-oxocyclohexanecarboxylate gave the adduct, which was ring closed in Dowtherm to 7,9,10,1 1-tetrahydro[1,2,5] thiadiazolo[3,4-c]acridin-6(8H)one (VIII) (70%). Chlorination of VIII with phosphorus oxychloride gave 6-chloro-7,8,9,10-tetrahydro[1,2,5]thiadiazolo[3,4-c]acridine (IX) (84%), which was condensed with 3-(dimethylamino)-1-propanethiol hydrochloride in phenol yielding 6-[ [3-(dimethylamino)propyl]thio]-7,8,9,10-tetrahydrof 1,2,5]-thiadiazolo[3,4-c]acridine (X) (27%). 6-[ [3(1)imethylamino)propyl]thio]-8,9-dihydro-7H-cyclopenta[b] [1,2,5]thiadiazolo[3,4-h]quinoline (XIII) (25%) was prepared similarly from IV and a mixture of methyl and ethyl 2-oxocyclopentanecarboxylate via 7,8,9,10-tetrahydro-6H-cyclopenta[b][1,2,5]thiadiazolo[3,4-h]quinolin-6-one (XI) (85%) and 6-chloro-8,9-dihydro-7H-cyclopenta[b][1,2,5]thiadiazolof3,4-h]quinoline (XII) (56%). The effects of compounds VII-XIII as inhibitors of platelet aggregation are discussed. 相似文献
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I. B. Starchenkov V. G. Andrianov A. F. Mishnev 《Chemistry of Heterocyclic Compounds》1998,34(9):1081-1085
The reduction of 1,2,3-triazolo[4,5-e]furazano[3,4-b]pyrazine 6-oxide was investigated. By means of data from x-ray crystallographic analysis it was shown that there is a relation between the aromaticity and the structure of the obtained triazoles.For communication 5, see [1].Latvian Institute of Organic Synthesis, Riga LV-1006. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1259–1264, September, 1998. 相似文献
8.
V. G. Andrianov I. B. Starchenkov A. F. Mishnev 《Chemistry of Heterocyclic Compounds》1997,33(8):977-981
The corresponding 7-substituted furazano[3,4-b]tetrazolo[1,2-d]pyrazines were obtained by nucleophilic substitution of the azido group in 7-azidofurazano[3,4-b]tetrazolo[1,2-d]pyrazine. It was shown that these compounds exist in the tetrazole form in the crystalline state; in solutions, a tautomeric equilibrium is observed between the azide and tetrazole forms. Further reaction with nucleophiles leads to the production of 5,6-disubstituted furazano[3,4-b]pyrazines.For Communication 1, see [2].Latvian Institute of Organic Synthesis. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1120–1124, August, 1997. 相似文献
9.
A method was developed for the synthesis of 5,6-dichlorofurazano[3,4-b]pyrazine (a compound with easily removed leaving groups). The optimum conditions for their substitution by various nucleophiles were determined.For Communication 2, see [1].Latvian Institute of Organic Synthesis, Riga. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1402–1416, October, 1997. 相似文献
10.
Alain Merschaert Pascal Boquel Hugo Gorissen Jean-Pierre Van Hoeck Alfio Borghese Luc Antoine Vincent Mancuso Anne Mockel Michel Vanmarsenille 《Tetrahedron letters》2006,47(47):8285-8288
We have developed a new synthesis of 3,4-disubstituted-1,2,5-thiadiazoles. The methodology is based on the ring opening of readily available 3,4-dichloro-1,2,5-thiadiazole with metal amides to afford a stable synthon, which is then transformed into the 3,4-disubstituted-1,2,5-thiadiazole derivatives via two consecutive reactions with O-, S-, N- or C-nucleophiles. 相似文献
11.
The synthesis and the optical and electrochemical properties of thiophene end capped oligo(2,3-alkylthieno[3,4- b]pyrazine)s are presented. The optical absorption rapidly shifts to lower energies with increasing chain length, caused in almost equal amounts by a rise of the HOMO and a lowering of the LUMO levels. The optical band gap of the polymer is estimated to be 1.13 +/- 0.07 eV. Extrapolated redox potentials indicate that the polymer is a small band gap p-type material. 相似文献
12.
Ivanova V. V. Fedorenko A. K. Starosotnikov A. M. Bastrakov M. A. 《Russian Chemical Bulletin》2022,71(8):1826-1829
Russian Chemical Bulletin - A number of [1,2,5]selenadiazolo[3,4-b]pyridines were synthesized on the basis of readily available 5-R-2,3-diaminopyridines. It was found that these compounds can be... 相似文献
13.
Chmovzh T. N. Knyazeva E. A. Krukovskaya N. V. Rakitin O. A. 《Russian Chemical Bulletin》2020,69(11):2167-2170
Russian Chemical Bulletin - The reaction of 4,7-dibromo[1,2,5]thiadiazolo[3,4-d]pyridazine with alcohols and sodium alkoxides was evaluated under various conditions. Depending on the reaction... 相似文献
14.
Benzo [1,2-c:3,4-c′:5,6-c″] tris [1,2,5] thiadiazole (1) was synthesized from benzo [1,2-c:3,4-c′] - bis [1,2,5] thiadiazole (11) . Nitration of 11 gave compound 15 , which on direct amination gave nitroamine 17 . Reduction of 17 gave diamine 18 , and cyclization of 18 with thionyl chloride gave 1 . Diamine 18 was also cyclized with selenium oxychloride, glyoxal, 9,10-phenanthrene-quinone, and formic acid to give the compounds 4, 5, 19 , and 6 , respectively. A new procedure for the preparation of 2,1,3-benzothiadiazole (7) from o-phenylenediamine was used. 相似文献
15.
G. Kh. Khisamutdinov V. L. Korolev T. N. Parkhomenko V. M. Sharonova E. S. Artem'eva I. Sh. Abdrakhmanov S. P. Smirnov B. I. Ugrak 《Russian Chemical Bulletin》1993,42(10):1700-1702
New methods for the synthesis of 1,2,4-triazolo[4,3-d]-1,2,4-triazolo[3,4-f]furazano[3,4-b]pyrazines with functional substituents of various types are proposed and some properties of these compounds are studied.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1776–1778, October, 1993. 相似文献
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17.
The synthesis of some pyrido[3,4-b]pyrano[3,4-b]indoles ( 3 ) from 3-hydroxy-4-(3-indolyl)piperidines ( 6 ) is reported. 相似文献
18.
Heterocycles bearing a symmetrical triazole or 1,3,4-thiadiazole ring system are reported to show a broad spectrum of biological activities.[1,2] The 1,2,4-triazole nucleus has been recently incorporated into a wide variety of therapeutically interesting drugs including H1/H2 histamine receptor blockers, cholinesterase active agents, CNS stimulants, antianxiety and sedatives[3] Coumarins are nowadays an important group of organic compounds that used as bactericides, fungicides,anti-inflammatory, anticoagulant, anti-HIV and antitumour agents.[4,5] Keeping in view the biological importance of the above mentioned heterocyclic compounds and in continuation of our search for biologically active nitrogen and sulphur heterocycles, a series of s-triazolo[3,4-b]-1,3,4-thiadiazole derivatives was synthesized. 相似文献
19.
P. Giori A. C. Veronese T. Poli C. B. Vicentini M. Manfrini M. Guarneri 《Journal of heterocyclic chemistry》1986,23(2):585-588
The reaction of pyrazolo[4,3-c][1,2,5]oxadiazin-3(5H)-ones 1 with carbanions prepared in situ from compounds containing an activated methylene group afforded pyrazolo[3,4-b]pyrazines 4–13 in good yields. The possible reaction mechanism is proposed and discussed. 相似文献
20.
I. A. Utepova A. A. Musikhina Yu. A. Kvashnin M. A. Shcherbakova P. O. Serebrennikova G. L. Rusinov O. N. Chupakhin 《Russian Chemical Bulletin》2011,60(12):2531-2535
A direct C-C-coupling of ferrocenyl- and cymantrenyllithium with 5-(het)aryl-1,2,5- oxadiazolo[3,4-b]pyrazines was accomplished. Main characteristics of the S N H-reaction products were obtained, as well as crystallographic data on the spatial structure of oxadiazolopyrazinylferrocenes and -cymantrenes synthesized. 相似文献