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1.
M. Mercedes Blanco Isabel A. Perillo Celia B. Schapira 《Journal of heterocyclic chemistry》1999,36(4):979-984
A number of 8-hydroxy-6-methyl-1,6-naphthyridin-5(6H)-one-7-carboxylic acid alkyl esters 3 and the isomeric 5-hydroxy-7-methyl-1,7-naphthyridin-8(7H)-one-6-carboxylic acid alkyl esters 4 were synthesized from acyclic precursors obtained starting from quinolinic anhydride 5. Thus, methanolysis of 5 afforded the hemiester 6 which treated with oxalyl chloride and sarcosine ethyl ester gave 3-(N-ethoxycarbonylmethyl-N-methylcarbamoyl)pyridine-2-carboxylic acid methyl ester 8. Compound 8 was cyclized to naphthyridines 3a-e with sodium alkoxides. The isomeric naphthyridines 4a-c were obtained by cyclization of the open intermediary 2-(N-ethoxycarbonylmethyl-N-methylcarbamoyl)pyridine-3-carboxylic acid methyl ester 9 obtained by a route that involves treatment of 5 with sarcosine ethyl ester and esterification with diazomethane. Spectroscopic properties (1H nmr, uv, ir) of compounds 3 and 4 are discussed and confirmed the proposed structures. 相似文献
2.
Condensation of the tetrahydropyranyl ether of the α-hydroxyalkyl-thioamides with 3-bromo-4-hydroxy-2-pentanones yields DL -2-(α-hydroxyalkyl)-4-methyl-5-(β-hydroxyethyl)-thiazoles. By oxidation with chromic anhydride 2-hydroxymethyl-4-methyl-5-(β-acetoxyethyl)-thiazole yields the corresponding 2-formyl derivative. The latter compound reacted with GRIGNARD complexes gives the homologous DL -2-(α-hydroxyalkyl)-4-methyl-5-(β-hydroxyethyl)-thiazoles. This is a general method for the synthesis of the thiazole part of the «active aldehydes». 2-Acetyl-4-methyl-5-(β-hydroxyethyl)-thiazole is also obtained by chromic oxidation of the suitable methylthiazol-2-yl-carbinol. The condensation of the thioamides obtained from the α-ethoxycarbonyl-nitriles with 3-bromo-5-acetoxy-2-pentanone results in the DL -2-(α-ethoxycarbonyl-alkyl)-4-methyl-5-(β-acetoxyethyl)-thiazoles. The α-hydroxyl function is introduced into the 2-(α-ethoxycarbonyl-alkyl) group by chlorination with sulfuryl chloride and replacement of the introduced chlorine by acetate. The latter compounds are the esters of the thiazole part of the «active α-oxo-carboxylic acids» (e.g. active pyruvate, etc.). The reaction of 2-(α-hydroxyalkyl)-4-methyl-5-(β-hydroxyethyl)-thiazoles and 2-(α-ethoxycarbonyl-α-acetoxy-alkyl)-4-methyl-5-(β-acetoxyethyl)-thiazoles, respectively, with alkyl, alkenyl and aralkyl haloids, or with 2-methyl-4-amino-5-bromomethyl-pyrimidine hydrobromide results in the quaternary thiazolium compounds belonging to the group of the active aldehydes, active α-oxo-carboxylic acids, etc. According to this method 2-hydroxymethyl-thiamine bromide hydro-bromide has been synthesized, which can be considered as the pyrophosphate-free «active formal-dehyde». The 2-α-hydrogen atom in 2-(α-hydroxyalkyl)-thiazolium compounds cannot be replaced by deuterium under conditions similar to those used for the H → D exchange in thiamine. The main peaks in the mass spectra of 2-(α-hydroxyalkyl) substituted thiazoles and thiazolium quaternary salts are listed. 相似文献
3.
E. Yu. Shasheva N. I. Vikrishchuk L. D. Popov V. I. Minkin M. E. Kletskii M. Yu. Antipin A. D. Vikrishchuk I. E. Mikhailov 《Russian Journal of Organic Chemistry》2010,46(7):1079-1084
Alkylation of 3-substituted 5-(2-hydroxyphenyl)-1H-1,2,4-triazoles with chloroacetonitrile gave hitherto unknown N-cyanomethyl derivatives whose structure was determined by
X-ray analysis and 1H and 13C NMR spectroscopy. Condensation of substituted [3-(2-hydroxyphenyl)-1H-1,2,4-triazol-1-yl]acetonitriles at the activated methylene group with acetone led to the formation of new 3-methyl-2-triazolylbut-2-enenitrile
derivatives. 相似文献
4.
Marina Cindric Tanja Kajfe Novak Krunoslav Uarevic 《Journal of Molecular Structure》2005,750(1-3):135-141
Two macrocyclic ligands, N,N′-propylene-diylbis[3-(1-aminoethyl)-6-methyl-2H-pyran-2,4(3H)-dione] I and N,N′-phenylene-diylbis[3-(1-aminoethyl)-6-methyl-2H-pyran-2,4(3H)-dione] II, have been prepared by the condensation of dehydroacetic acid (3-acetyl-4-hydroxy-6-methyl-2H-pyran-2-one) with 1,2-phenylenediamine and 1,3-propylenediamine. They have been characterized by means of elemental analysis, IR spectroscopy as well as by X-ray crystallography. The molecular structures of the compounds I and II can be described as consisting of two β-enaminone-2-pyrone rings interlaced with either alkyl chain in I or phenyl ring in II. The X-ray studies confirmed the existence of strong N–HO intramolecular hydrogen bonds in both structures. Their lengths are in accordance to lengths of RAHB intramolecular hydrogen bonds in 1,3-diketones, aryl-hydrazones, β-enaminones and related heterodienes (2.5–2.6 Å) [P. Gilli, V. Bertolasi, V. Ferretti and G. Gilli, J. Am. Chem. Soc., 122 (2000) 10405]. 相似文献
5.
Rakesh Kumar Gueijun Ji Leonard I. Wiebe Edward E. Knaus 《Journal of heterocyclic chemistry》1991,28(3):711-715
5-Iodo-3′-O-(1-methyl-1,4-dihydropyridyl-3-carbonyl)-2′-deoxyuridine (15a) , 5-vinyl-3′-O-(1-methyl-1,4-di-hydropyridyl-3-carbonyl)-2′-deoxyuridine (15b) and (E)-5-(2-iodovinyl)-3′-O-(1-methyl-1,4-dihydropyridyl-3-carbonyl)-2′-deoxyuridine (15c) were synthesized for future evaluation as lipophilic brain-selective antiviral agents for the treatment of herpes simplex encephalitis. Quaternization of the 3′-O-(3-pyridylcarbonyl) compounds 10–11 using iodomethane afforded the corresponding 1-methylpyridinium salts 12–13 which were reduced with sodium dithionite to yield the corresponding 3′-O-(1-methyl-1,4-dihydropyridyl-3-carbonyl) compounds 14–15. 相似文献
6.
Yu. O. Remizov L. M. Pevzner M. L. Petrov 《Russian Journal of General Chemistry》2018,88(7):1402-1410
By arylation of 2-methyl-3-acetylfuran via the Gomberg–Bachmann reaction 5-(4-ethoxycarbonylphenyl)-, 5-(2-nitrophenyl), and 5-(4-nitrophenyl)-2-methyl-3-acetylfurans were synthesized. Carboethoxyhydrazones of 2-methyl-5-phenyl-3-acetylfuran and its phenyl-substituted analogs when treated with thionyl chloride form 4-(5-aryl-2-methylfuran-3-yl)-1,2,3-thiadiazoles by the Hurd–Mori reaction. Thermal stability of obtained compounds increases with the increase in electron-acceptor action of substituent in phenyl ring. Opening of thidiazole ring in the compounds synthesized under the action of potassium tert-butylate in THF in the presence of alkyl iodides leads to the corresponding alkylthioethynylfurans. Performing the reaction with potassium carbonate in DMF in the presence of excess morpholine permits the preparation of (2-methyl-5- arylfuran-3-yl)thioacetylmorpholides. 相似文献
7.
Reaction of 2-(2-bromophenyl)-2-methyl-1,3-dioxolane with lithium (1,1-dimethylethyl)amide, lithium (2,2-dimethylpropyl)amide, lithium (1,1-dimethylpropyl)amide gave the corresponding N-(alkyl)-3-(2-methyl-1,3-dioxolan-2-yl)benzenamines in moderate yields. 1-[3-[(1,1-Dimethylethyl)amino]phenyl]ethanone ( 4 ) was prepared in over 80% yield from 2-(2-bromophenyl)-2-methyl-1,3-dioxolane ( 2 ). 相似文献
8.
A. S. Amarasekara O. S. Owereh K. A. Lyssenko T. V. Timofeeva 《Journal of Structural Chemistry》2009,50(6):1159-1165
The Schiff base derivatives prepared from 4-acetyl-5-methyl-2-phenyl-2,4-dihydro-pyrazol-3-one and alkyl amines are shown
to remain exclusively in the amine-one(I) tautomeric form in chloroform solutions at room temperature using a combination
of 1H, 13C, APT, COSY, HMQC, and HMBC NMR spectroscopic methods. The crystal structure of 5-methyl-2-phenyl-4-{1-[(pyridin-2-ylmethyl)-amino]-ethylidene}-2,4-dihydro-pyrazol-3-one
showed that this 4-acylpyrazolone Schiff base stays in the amine-one(I) form in the solid state as well, and the solid state
structure supports the fact that strong hydrogen bonding between amine hydrogen and the pyrazolone C3 carbonyl oxygen helps to stabilize the amine-one(I) tautomer. 相似文献
9.
The title compounds, bearing an alkyl and/or bromine substituent on nitrogen, were synthesized. Unlike 5-bromo-6-methyluracil, 4-bromo-5-methyl-(2H)-1,2,6-thiadiazin-3-(6H)one 1,1-dioxides have the ability to act as a bromonium ion source. 相似文献
10.
Reactions of 6-Amino-5-Cyano-3-Methyl-1,4-Diphenyl-1H 4H-Pyrano[2,3-C]Pyrazole and its Methanimidate
Reaction of 6-amino-5-cyano-3-methyl-1,4-diphenyl- 1H,4H-pyrano[2,3-c]pyrazole 1 with triethyl orthoformate in acetic anhydride gave its methanimidate 2, which reacts with primary aliphatic and aromatic amines to give 4,6-dihydro-3-methyl-1,4-diphenyl-6- (alkyl)pyrazolo[4′,3′:5,6]pyrano[2,3-d]pyrimidine-5(lH)- imine 3 and the starting compound 1 , respectively. Treatment of 1 with o-aminophenol gave 5-(2-benzoxalyl)- 1,4-dihydro-3-methyl-1,4-diphenylpyrano[2,3-c]pyrazol- 6-amine 9. 相似文献
11.
Mohamed Salah K. Youssef Ahmed A. Omar 《Monatshefte für Chemie / Chemical Monthly》2007,138(10):989-995
Summary. 5-Amino-3-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-7-phenyl-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile was synthesized via the reaction of 4-(2-aminothiazol-4-yl)-3-methyl-1-phenyl-2-pyrazolin-5-one with benzylidene malononitrile and was then transformed
to related fused heterocyclic systems. The antifungal and antibacterial studies revealed in some cases excellent biocidal
properties. 相似文献
12.
V. S. Matiichuk M. A. Potopnyk N. D. Obushak 《Russian Journal of Organic Chemistry》2010,46(10):1550-1557
Bromination of ethyl 1-aryl-4-acetyl-5-methyl-1H-pyrazole-3-carboxylates gave ethyl 1-aryl-4-(bromoacetyl)-5-methyl-1H-pyrazol-3-carboxylates which were used to alkylate benzenethiol and heterocyclic thiones at the sulfur atom. Reactions of
the resulting S-alkylation products with hydrazine or methylhydrazine involved closure of pyridazine ring to afford 2-aryl-3-methyl-4-[phenyl(or
hetaryl)sulfanylmethyl]-6,7-dihydro-2H-pyrazolo[3,4-d]pyridazin-7-ones. 相似文献
13.
E. A. Kaigorodova L. D. Konyushkin M. E. Niyazymbetov S. N. Kvak V. N. Zaplishny V. P. Litvinov 《Russian Chemical Bulletin》1994,43(12):2095-2099
A series of substituted 2-alkyl(aryl-, hetaryl-)thiopyridines was prepared by cathodic electrolysis of thiols in the presence of 2-chloro-3-cyano-4-methoxymethyl-6-methylpyridine or 4-chloro-6-methyl-3-oxo-1H-furo[3,4-c]pyridine. The reaction of 3-cyano-4-methoxymethyl-6-methyl-2(1H)-thiopyridone with alkyl halides in the presence of KOH is regioselective and leads toS-alkyl derivatives. The advantages of electrosynthesis for the preparation of 2-alkylthiopyridines fused with 2(5H)-furanone and of 3-aminothieno [2,3-b]pyridines is demonstrated.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2215–2219, December, 1994. 相似文献
14.
Alkylation and aldol reactions carried out on axially chiral, diastereoenriched oxazolidinedione derivatives were found to be highly stereoselective with respect to substitution at the 5-position of the oxazolidindione ring. Thus, diastereoenriched 5-methyl-3-(o-iodophenyl)-2-thioxo-4-oxazolidinone and 5-methyl-3-(o-aryl)-2,4-oxazolidinediones were prepared and lithiated at C-5 of the oxazolidine ring and the subsequent electrophilic quench with alkyl halides or benzaldehyde yielded products with the same diastereomer ratios as the starting materials. 相似文献
15.
Conclusions The oxidation of 2,4-dioxo-3-(3-hydroxybutyl)-1,2,3,4,6,7-hexahydro-11bH-benzo[a]quinolizine with either the Sarett complex or Jones reagent gives predominantly 5-oxo-2-methyl-2,3,7,8-tetrahydro-4H,5H-benzo[a]pyrano[2,3-g]quinolizine, while oxidation with CrO3 in AcOH solution gives 8,9,14-trioxo-12-methyl-5,6,8,9,10,11,15,15a-octahydro-13-oxa-12H,14H-azepino[2,1-a]isoquinoline.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1611–1614, July, 1973. 相似文献
16.
E. A. Lashmanova V. S. Larina A. K. Shiryaev 《Russian Journal of Organic Chemistry》2017,53(8):1249-1252
Alkylation products were obtained from ethyl 2-(hydroxyimino)-7-methyl-3-oxo-5-aryl-2,3- dihydro-5H-[1,3]thiazolo[3,2-a]pyrimidin-6-carboxylates at the treatment with alkyl halides, dimethyl sulfate, and diazomethane. Diazomethane alkylated the initial substrate at the oxygen atom of the carbonyl group of the thiazolidine fragment, the other reagents, at the oxygen atom of the hydroxyimino group. 相似文献
17.
Kakehi A Suga H Yamauchi Y Yasuraoka K Kobayashi T Ohta A 《Chemical & pharmaceutical bulletin》2004,52(11):1316-1321
The title compounds, readily available from the S-alkylation of pyridinium 1-[alkylthio(thiocarbonyl)](ethoxycarbonylacetyl)methylides with alkyl halides or alkyl bromoacetates, were treated with a base and then a dehydrogenating agent to provide some unique products such as 3-[bis(alkylthio)methylene]-2(3H)-indolizinones and dialkyl 7-methyl-4-oxo-1,4,8,8a-tetrahydro-1,4-thiazino[3,4,5-cd]indolizine-1,5-dicarboxylates. On the other hand, similar reaction of these pyridinium salts in the absence of the dehydrogenating agent afforded alkyl 2-hydroxyindlizine-3-carboxythiolates, whose yields were increased by adding trifluoroacetic acid to the reaction mixture. The structures of some products were confirmed by the X-ray analyses. 相似文献
18.
F. Firoozi K. Javidnia M. Kamali A. Fooladi A. Foroumadi A. Shafiee 《Journal of heterocyclic chemistry》1995,32(1):123-128
Starting from readily available ethyl-4-nitropyrrole-2-carboxylate ( 1 ), substituted 1-methyl-2-(1,3,4-thiadiazol-2-yl)-4-nitropyrroles and 1-methyl-2-(1,3,4-oxadiazol-2-yl)-4-nitropyrroles were prepared. The reaction of 1 with diazomethane gave ethyl 1-methyl-4-nitropyrrole-2-carboxylate ( 2 ). Reaction of compound 2 with hydrazine hydrate afforded the corresponding hydrazide 3 . The reaction of 3 with formic acid yielded 1-(1-methyl-4-nitropyrrole-2-carboxyl)-2-(formyl)hydrazine ( 7 ). Refluxing of the latter with phosphorus pentasulfide in xylene yielded compound 6 in 40% yield. Reaction of compound 7 with phosphorus pentoxide afforded compound 9 . Reaction of compound 3 with 1,1′-carboxyldiimidazole in the presence of triethylamine yielded 2-(1-methyl-4-nitro-2-pyrrolyl)-1,3,4-oxadiazoline-4(H)-5-one ( 11 ). Refluxing compound 3 with cyanogen bromide in methanol gave compound 12 . Compound 13 could be obtained through the reaction of compound 3 with carbon disulfide in basic medium. Alkylation of compound 13 afforded the correspanding alkylthio derivative 14 . Reaction of 1-methyl-4-nitropyrrole-2-carboxylic acid ( 15 ) with thiosemicarbazide and phosphorus oxychloride gave 2-amino-5-(1-methyl-4-nitro-2-pyrrolyl)-1,3,4-thiadiazole ( 16 ). Sandmeyer reaction of compound 16 yielded 2-chloro-5-(1-methyl-4-nitro-2-pyrrolyl)-1,3,4-thiadiazole ( 17 ). Refluxing of the latter with thiourea afforded 2-(1-methyl-4-nitro-2-pyrrolyl)-1,3,4-thiadiazoline-4(H)-5-thione ( 18 ). Alkylation of compound 18 gave the corresponding alkylthio derivative 19 . Oxidation of the latter with hydrogen peroxide in acetic acid yielded 2-(1-methyl-4-nitro-2-pyrrolyl)-5-methylsulfonyl-1,3,4-thiadiazole ( 20 ). 相似文献
19.
Reaction of 4-imino-1-methyl-5-phenyl-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-d]pyrimidine-6-thione with unsaturated alkyl halides gives 4-imino-6-methallylthio(cinnamylthio, allylthio)-1-methyl-5-phenyl-4,5-dihydro-1H-pyrazolo[3,4-d]pyrimidines. 相似文献
20.
Yasutaka Kayama Takeshi Hara Kazuhiko Itoh Tamiko Sunami 《Journal of heterocyclic chemistry》1977,14(1):171-172
A convenient synthesis of a 4H-pyrroIo[1,2-α][1,4 ]benzodiazepine is described. 2,5-Di-methoxy-2-melhyl-5-phthalimidomethyltetrahydrofuran ( 3 ) was prepared starting from 2-methyl-5-phthalimidomelhylfuran ( 1 ). The condensation of 2-amino-5-chlorobenzophcnone with 3 to give 5-chloro-2-(2-methyl-5-phthalimidomethylpyrro]-1-yl)benzophenone ( 4 ), the treatment of which with hydrazine hydrate afforded 8-chloro-1-methyl-4H-pyrrolo[1,2-α] [1,4]benzodiazepine ( 5 ). 相似文献