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1.
The o-diamine, 3,4-diamino-1,2,5-thiadiazole ( 2 ), was synthesized from 3,4-dichloro-1,2,5-thiadiazole ( 3 ) hy three methods. Aqueous glyoxal cyclized 2 into [1,2,5]thiadiazolo[3,4–6]-pyrazine ( 14 ). 3,4-Dichloro-1,2,5-thiadiazole 1,1-dioxide ( 18 ) reaeted with 2 to give 1,3-dihydro-bis[1,2,5]thiadiazolo[3,4-b:3′,4′-e]pyrazine 2,2-dioxide ( 19 ). The reaction of 2 with selenium oxyehloride led to [1,2,5]selenadiazolo[3,4-c] [1,2,5]thiadiazole ( 12 ). Ring closure of 2,3-diaminoquinoxaline ( 4 ) with thionyl chloride or selenium oxychloride gave [1,2,5]thiadiazolo-[3,4-b]quinoxaline ( 21 ) and [1,2,5]selenadiazolo[3,4-b]quinoxaline ( 22 ), respectively. Sulfurous acid reduced 21 to the 4,9-dihydro derivative 23 , which was reoxidized to 21 with chloranil. Aqueous hase hydrolyzed 21 to 4 via the hydrated intermediate 24 . Aqueous glyoxal cyclized 4 to the covalent hydrate of pyrazino[2,3-b]quinoxaline ( 26 ), 27 , which was dehydrated to 26 . Compound 26 underwent rapid addition of two alcohols in a process analogous to covalent hydration. 相似文献
2.
3-(4′-Pyridyl)-4-amino-5-mercapto-1,2,4-triazole(1)reacted with aroyl isothiocyanates2a-1 to yield twelve novel 3-(4′-pyridyl)-6-aroylamino-S-triazolo[3,4-b]-1,3,4-thiadiazoles,4a-1.Triethylamine was necessary for the condensation of 1 with phenyl isothiocyanate(3)to give 3-(4′-pyridyl)-6-phenylamino-S-triazolo[3,4-b]-1,3,4-thiadiazole(6).The structures were confirmed bythe elemental and spectral analyses.Their antibacterial activity against B.Subtilis,E.Coli,E.aerogenes and S.aureus was observed preliminary. 相似文献
3.
Yuh-Wen Ho 《中国化学会会志》1999,46(6):955-962
Coupling the diazonium salt of 3-amino-2-cyano-4,6-dimethylthieno[2,3-b]pyridine 1 with malononitrile 2 gave 2-cyano-3-(hydrazonomalononitrile)-4,6-dimethylthieno[2,3-b]pyridine 3 which then reacted with hydrazine compounds 4a-4h to yield corresponding 2-cyano-3-(3,5-diamino-1-substituted-pyrazol-4-yl)azo-4,6-dimethylthieno[2,3-b]pyridines 5a-5h. The 2-cyano-3-(2-amino-5,7-disubstituted-pyrazolo-[1,5-a]pyrimidine-3-yl)azo-4,6-dimethylthieno[2,3-b]pyridines 7a-7f were obtained in good yield by the cyclocondensation reaction of 2-cyano-3-(3,5-diamino-pyrazol-4-yl)azo-4,6-dimethylthieno[2,3-b]pyridine 5a with the appropriate 1,3-diketones 6a-6f under acidic condition. 相似文献
4.
Pter Mtyus Luca Szalay Endre Kasztreiner Gyula Jerkovich Gyrgy Rabloczky 《Journal of heterocyclic chemistry》1989,26(3):739-740
Synthesis of derivatives 4 and 6 of two novel tricyclic ring systems, 1, 2, 4-triazolo[3, 4-c]pyrimido[5, 4-b]-[1, 4]oxazine and imidazo[1, 2-c]pyrimido[5, 4-b][1, 4]oxazine, respectively is described. Although the parent pyrimido[5, 4-b]oxazines possess positive inotropic activity, the tricyclic compounds are practically inactive. 相似文献
5.
《Arabian Journal of Chemistry》2014,7(6):955-963
A series of 3-diphenylmethyl-6-substituted-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazole derivatives (4a–j and 5a–d) were synthesized by condensation of 4-amino-5-diphenylmethyl-4H-1,2,4-triazole-3-thiol with various substituted aromatic acids and aryl/alkyl-isothiocyanates. The structures of synthesized compounds were characterized by elemental analysis, IR, 1H NMR, 13C NMR and mass spectroscopic studies. These compounds were tested in vivo for their anti-inflammatory activity. The compounds which showed activity comparable to the standard drug ibuprofen were screened for their analgesic, ulcerogenic, lipid peroxidation and hepatotoxic effects. Compounds 6-(4-chlorophenyl)-3-diphenylmethyl-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazole (4a) and 6-(2,4-dichlorophenyl)-3-diphenylmethyl-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazole(4c) emerged as the most active compounds of the series and were moderately more potent than the standard drug ibuprofen. 相似文献
6.
Marjo Merslavi
Andrej Petri
Branko Stanovnik Miha Tiler 《Journal of heterocyclic chemistry》1989,26(3):581-583
The transformations of 7-methyl-7H- and 8-methyl-8H-pyrazolo[4, 3-d]tetrazolo[1, 5-b]pyridazines 1, 2, 9 and 10 into 8-methyl-8H- and 9-methyl-9H-pyrazolo[3, 4-H]-s-triazolo[4, 3-b]pyridazines 7 and 8 , and 1-methyl-1H-and 2-methyl-2H-imidazo[1, 2-b]pyrazolo[3, 4-d]pyridazines 13 and 14 are described. 相似文献
7.
Abdou O. Abdelhamid Zeineb H. Ismail Soad M. Abdel-Gawad Moustafa M. Ghorab Anhar Abdel-Aziem 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):58-75
Thieno[2,3-b]pyridines were synthesized from 6-benzofuran-2-yl-4-phenyl-2-sulfanylpyridine-3-carbonitrile and each of chloro acetone, ethyl chloroacetate, ω -bromoacetophenone, and chloroacetonitrile. These compounds were conveniently converted into novel pyrido[4′,5′:4,5]thieno[3,2-d]pyrimidines. Also, 2,3-dihydro-1,3,4-thiadiazole was synthesized from hydrazonoyl halides and 2-benzofuran-2-yl-3-(phenylamino)-3-thioxopropanenitrile. The structures of the products have been elucidated by elemental analyses, spectral data studies, and alternative syntheses whenever possible. The newly synthesized compounds were tested towards microorganisms. 相似文献
8.
The 13C nmr spectra of 2- or 3-monosubstituted furo[2,3-b]- 1a-1j , furo[3,2-b]- 2a-2j , furo[2,3-c]- 3a-3j and furo[3,2-c]pyridine derivatives 4a-4j are reported. Effects by change in annelation and substituent effects on 13C chemical shifts and carbon-proton coupling constants are discussed. The spectra of benzo[b]furan derivatives 5a-5j having the corresponding substituent are also reported for comparison. 相似文献
9.
A convenient synthesis of furo[3,2-b]pyridine and its 2- and 3-methyl derivatives from ethyl 3-hydroxypiconate ( 1 ) is described. The hydroxy ester 1 was O-alkylated with ethyl bromoacetate or ethyl 2-bromopropionate to give the diester 2a or 2b . Cyclization of compound 2a afforded ethyl 3-hydroxyfuro[3,2-b]pyridine-2-carboxylate ( 3 ) which in turn was hydrolyzed and decarboxylated to give furo[3,2-b]pyridin-3-(2H)-one ( 4a ). Cyclization of 2b gave the 2-methyl derivative 4b . Reduction of 4a and 4b with sodium borohydride yielded the corresponding hydroxy derivative 5a and 5b respectively, which were dehydrated with phosphoric acid to give furo[3,2-b]pyridine ( 6a ) and its 2-methyl derivative ( 6b ). 2-Acetylpyridin-3-ol ( 8 ) was converted to the ethoxycarbonylmethyl ether ( 9 ) by O-alkylation with ethyl bromoacetate, which was cyclized to give 3-methylfuro[3,2-b]pyridine-2-carboxylic acid ( 10 ). Decarboxylation of 10 afforded 3-methylfuro[3,2-b]pyridine ( 11 ). 相似文献
10.
A. Shafiee M. A. Ebrahimzadeh J. Shahbazi S. Hamedpanah 《Journal of heterocyclic chemistry》1998,35(1):71-75
Starting from the readily available aryl 2-methyl-5-phenyl-3-furyl ketones, 5-methyl-1H-1-phenylpyrazole-4-yl ketones and 4-methyl-2-phenyl-5-thiazolylcarboxaldehyde, a series of 2-phenyl-4-arylthieno[3,4-b]-furan, 2-phenyl-4-(p-methoxyphenyl)selenolo[3,4-b]furan, 4-aryl-1H-1-phenylthieno[3,4-c]pyrazole and 5-benzyl-2-phenylpyrrolo[3,4-d]thiazole were prepared in high yield. 相似文献
11.
O. B. Smirnova T. V. Golovko L. M. Alekseeva V. V. Chernyshev V. G. Granik 《Russian Chemical Bulletin》2010,59(1):177-185
The reactions of 2-dicyanomethylidene-3-ethoxymethylidene-2,3-dihydroindole with hydrazine hydrate and phenylhydrazine afforded
2,3-diamino-4-cyanopyrido[4,3-b]indole and 3-amino-2-anilino-4-cyanopyrido[4,3-b]indole, respectively, and the reactions of the latter compounds with dimethylformamide diethyl acetal were studied. The reactions
of 2,3-diamino-4-cyanopyrido[4,3-b]indole with benzaldehyde, ethyl acetoacetate, and acetylacetone were investigated. First representatives of new heterocyclic
systems, viz., [1,2,4]triazolo[1’,5’:1,6]-pyrido[4,3-b]indole and pyrazolo[1’,5’:1,2]pyrido[4,3-b]indole, were synthesized. The structure of ethyl 6-cyano-5-[(E)-(dimethylamino)methylideneamino]-2-methyl-7H-pyrazolo-[1’,5’:1,2]pyrido[4,3-b]indole-1-carboxylate was established by X-ray diffraction. 相似文献
12.
Yuh-Wen Ho 《中国化学会会志》1999,46(6):947-953
The reaction of 3-amino-4,6-dimethyl-2-thieno[2,3-b]pyridine carbohydrazide ( 1 ) with appropriate 1,3-diketones 2a-2d in glacial acetic acid afforded 3-amino-2-[(3,5-disubstituted-pyrazo)-1-yl)carbonyl]-4,6-dimethylthieno[2,3-b]pyridines 3a-3d. 3-Amino-2-[(5-amino-3,4-disubstituted-pyrazol-1-yl)carbonyl]-4,6-dimethylthieno[2,3-b]pyridines 5a-5h were also prepared by treatment of carbohydrazide 1 with appropriate alkylethoxymethylenes and ketene dithioacetals 4a-4h , respectively. 相似文献
13.
Yoshifumi Watanabe Hirotaka Yoshiwara Munefumi Kanao 《Journal of heterocyclic chemistry》1993,30(2):445-451
The syntheses of 4-(benzo[b]furan-3-yl)piperidines, 4-(benzo[b]furan-2-yl)piperidines and 4-(benzo[b]thiophen-3-yl)piperidines with 5-HT2 antagonist activity are described. Reaction of 1-acetyl-4-(2,4-difluorobenzo-yl)piperidine 2 with methyl glycolate gave methyl 6-fluoro-3-(1-acetylpiperidin-4-yl)benzo[b]furan-2-carboxylate 3 , which was converted to 2-[2-[4-(benzo[b]furan-3-yi)piperidin-1-yl]ethyl-5,6,7,8-tetrahydro-1,2,4-triazolo-[4,3-a]pyridin-3(2H)-one hydrochloride 9 . Analogous benzo[b]furans 17a-d and benzo[b]thiophenes 10a,b and 18a were prepared by a similar method. Cyclization of 4-fluoro-2-(4-pyridinylmethoxy)acetophenones 20a,b afforded 4-(benzo[b]furan-2-yl)pyridines 21a,b , which were converted to 2-[2-[4-(benzo[b]furan-2-yl)-piperidin-1-yl]ethyl-5,6,7,8-tetrahydro-1,2,4-triazolo[4,3-a]pyridin-3(2H)-one hydrochlorides 24a,b. Among them, benzo[b]furans 9 and 17a,d and benzo[b]thiophenes 10 and 18a showed potent 5-HT2 antagonist activity in vitro. 相似文献
14.
Marvin L. Tedjamulia Yoshinori Tominaga Raymond N. Castle Milton L. Lee 《Journal of heterocyclic chemistry》1983,20(4):861-866
The synthesis of benzo[b]phenanthro[2, 3-d]thiophene ( 5 ), benzo[b]phenanthro[4, 3-d]thiophene ( 6 ), benzo-[b]phenanthro[2, 1-d]thiophene ( 9 ), benzo[b]phenanthro[3, 2-d]thiophene ( 14a ), anthra[1, 2-b]benzo[d]thiophene ( 24 ), anthra[2, 3-b]benzo[d]thiophene ( 29 ) and anthra[2, 1-b]benzo[d]thiophene ( 30 ) is described as well as the preparation of 13-methylbenzo[b]phenanthro[3, 2-d]thiophene ( 14b ). 相似文献
15.
16.
The synthesis of new tetracyclic systems and new stable tautomers of known systems 11H- 13 and 10H-imidazo[1, 2-b]pyrazolo[4, 3-d]-s-triazolo[3, 4-f]pyridazine 16 , 9H-pyrazolo[3, 4-d]bis-s-triazolo[4, 3-6:5′,1-f]-pyridazine 15 , 10H-pyrazolo[3, 4-d]bis-s-triazolo[4, 3-b:3′,4′-f]pyridazine 17 , and 10H-pyrazolo[4, 3-d)bis-s-triazolo[4, 3-6:5′,1′-f]pvridazine 18 is described. 相似文献
17.
Shunsaku Shiotani 《Journal of heterocyclic chemistry》1993,30(4):1035-1039
The preparation of 2-aminomethyl- 3a-d , 2-acetamidomethyl- 4a-d , 2-N,N-dimethylaminomethyl- 5a-d , 2-(1-hydroxy-2-nitroethyl)- 6a-d , 2-(1-hydroxyl-2-aminoethyl)- 7a-d and 2-(1-hydroxy-2-N,N-dimethylaminoethyl)- 8b-d derivatives of furo[2,3-b]-, furo[3,2-b]-, furo[2,3-c]- and furo[3,2-c]pyridine is described. 相似文献
18.
To determine the structures of two isomeric products, 2-phenacylidene-1,2-dihydro-4H-pyrido[2,3-b]pyrazin-3-one (2) and 3-phenacylidene-3,4-dihydro-1H-pyrido[2,3-b]pyrazin-2-one (3) obtained by condensation of 2,3-diaminopyridine (1) with ethyl benzoylpyruvate [1–3], these compounds were hydrolyzed to give 2-methyl-4H-pyrido[2,3-b]pyrazin-3-one (4) and 3-methyl-1H-pyrido[2,3-b]pyrazin-2-one (5) , respectively [4,5]. Both hydrolysates 4 and 5 were hydrogenated to afford 2-methyl-1,2-dihydro-4H-pyrido[2,3-b]pyrazin-3-one (6) and 3-methyl-3,4-dihydro-1H-pyrido[2,3-b]pyrazin-2-one (7) . The latter compound was identical with an unequivocally synthesized compound providing proof for the structures of all these compounds. 相似文献
19.
Yoshihisa Kurasawa Muneto Muramatsu Kaoru Yamazaki Setsuko Tajima Yoshihisa Okamoto Atsushi Takada 《Journal of heterocyclic chemistry》1986,23(2):633-635
The chlorination of the α-hydrazonoester 4 with phosphoryl chloride/pyridine gave 3-[α-(o-chlorophenylhydrazono)methoxycarbonylmethyl]-2-chloroquinoxaline 5 , whose cyclization with 1,8-diazabicyclo[5,4,0]-7-undecene afforded 3-methoxycarbonyl-1-(o-chlorophenyl)-1H-pyrazolo[3,4-b]quinoxaline 6 . The reaction of 6 with hydrazine hydrate provided 3-hydrazinocarbonyl-1-(o-chlorophenyl)-1H-pyrazolo[3,4-b]quinoxaline 7 , whose reactions with methyl and allyl isothiocyanates furnished 3-(2,3-dihydro-4-methyl-3-thioxo-4H-1,2,4-triazol-5-yl)-1-(o-chlorophenyl)-1H-pyrazolo[3,4-b]quinoxaline 2 and 3-(4-allyl-2,3-dihydro-3-thioxo-4H-1,2,4-triazol-5-yl)-1-(o-chloropheny)-1H-pyrazolo[3,4-b]quinoxaline 8 , respectively. Moreover, the reactions of 7 with triethyl orthoformate and orthoacetate gave 1-(o-chlorophenyl)-3-(1,3,4-oxadiazol-5-yl)-1H-pyrazolo-[3,4-b]quinoxaline 9a and 1(o-chlorophenyl)-3-(2-methyl-1,3,4-oxadiazol-5-yl)-1H-pyrazolo[3,4-b]quinoxaline 9b , respectively. 相似文献
20.
Talaat I. El-Emary 《中国化学会会志》1999,46(4):585-590
The reaction of 6-amino-5-cyano-3-methyl-1H-1-phenylpyrazolo[3,4-b]pyridine ( 2 ) and 6,7-dihydro-3-methyl-6-oxo-1H-1-phenylpyrazolo[3,4-b)]pyridine-5-carbonitrile ( 3 ) and 5-amino-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]-1H-pyrazolo[4′,3′-e]pyridine ( 12 ) with different reagents have been conducted to give newly condensed pyrazoloazines. 相似文献