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1.
Reaction of open-chain and cyclic sym-1,3-diones with N,N-dimethylformamide dimethyl acetal gave, generally in high yield, a series of sym-2-dimethylaminomethylene-1,3-diones which reacted with phenylhydrazine and methylhydrazine to afford, generally in satisfactory yield, a number of 1,5-disubstituted 4-acylpyrazoles. The applications and limits of this new pyrazole synthesis are presented and discussed.  相似文献   

2.
Reaction of ethyl or methyl 2-dimethylaminomethylene-3-oxoalkanoates with N-C-N dinucleophiles such as guanidine, acetamidine or benzamidine afforded in high yields the relative esters of 4-substituted 2-amino-, 2-methyl- or 2-phenyl-5-pyrimidinecarboxylic acids, respectively. These esters were hydrolyzed to the corresponding carboxylic acids, which were converted by heating to 4-substituted 2-pyrimidinamines, 2-methyl or 2-phenylpyrimidines, respectively, generally in excellent yields. The 4-unsubstituted ethyl 2-amino-, 2-methyl- and 2-phenyl-5-pyrimidinecarboxylates were obtained in moderate yields by reaction of the above dinucleophiles with ethyl 2,2-diformylacetate. These esters were hydrolyzed and the corresponding acids (with the exception of the 2-methyl derivative) were decarboxylated to give 2-pyrimidinamine and 2-phenylpyrimidine in satisfactory yields.  相似文献   

3.
The reaction of open-chain and cyclohexane sym-2-dimethylaminomethylene-1,3-diones with amidines and guanidine in refluxing ethanol gave, generally in good yields, a series of 5-acylpyrimidines and 7,8-dihydroquinazolin-5(6H)-ones, respectively. With formamidine (and in part acetamidine), 2-formylimino-1,3-diones were formed in general, as sole products or mixtures with the corresponding pyrimidines or dihydroquinazolinones.  相似文献   

4.
The reaction of open-chain and cyclohexane sym-2-dimethylaminomethylene-1,3-diones with hydroxylamine hydrochloride in refluxing methanol gave in good to moderate yields a series of 5-(alkyl)(phenyl)-4-acylisoxazoles and 6,7-dihydro-1,2-benzisoxazol-4(5H)-ones, respectively. As 3-unsubstituted isoxazoles, all these compounds easily isomerized with sodium methoxide to the corresponding 2-cyano-1,3-diones in high yields.  相似文献   

5.
Reaction of ethyl or methyl 3-oxoalkanoates with N,N-dimethylformamide dimethyl acetal gave, generally in excellent yields, a series of ethyl or methyl 2-dimethylaminomethylene-3-oxoalkanoates II which reacted with phenylhydrazine to afford the esters of 5-substituted 1-phenyl-1H-pyrazole-4-carboxylic acids III in high yields. Esters III were hydrolyzed to the relative 5-substituted 1-phenyl-1H-pyrazole-4-carboxylic acids which were converted by heating to 5-substituted 1-phenyl-1H-pyrazoles in excellent yields. Reaction of II with methylhydrazine afforded in general a mixture of 3- and 5-substituted ethyl 1-methyl-1H-pyrazole-4-carboxylates with the exception of IIg , which gave in high yield methyl 5-benzyl-1-methyl-1H-pyrazole-4-carboxylate, which was hydrolyzed to the relative pyrazolecarboxylic acid. This afforded by heating 5-benzyl-1-methyl-1H-pyrazole in quantitative yield.  相似文献   

6.
The reaction of dimedone, N-aryl-substituted acetoacetic acid amides, aryl aldehydes, and ammonium acetate gives 4,N-diaryl-2,7,7-trimethyl-5-oxo-1,4,5,6,7,8-hexahydro-3-quinoline carboxamides.  相似文献   

7.
Heating anilides (hydrazides) of 5-cyano-6-oxo-2-styrylnicotinic acids in polyphosphoric acid (PPA) leads to amides of 7-aryl-2,5-dioxo-6-phenyl(amino)-1,2,5,6,7,8-hexahydro-1,6-naphthyridine-3-carboxylic acids, which on heating with perchloric acid in acetic acid give the corresponding acids.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1809–1812, December, 2004.For Part 15 see [1].  相似文献   

8.
Reaction of ethyl or methyl 2-dimethylaminomethylene-3-oxoalkanoates with hydroxylamine hydrochloride in methanol solution afforded in high yields the relative esters of 5-substituted 4-isoxazolecarboxylic acids II . These esters were hydrolyzed generally with concentrated hydrochloric acid-acetic acid mixtures to the corresponding carboxylic acids in satisfactory yields. Ethyl or methyl esters II isomerized with sodium ethoxide or methoxide, respectively, to the corresponding esters or hemiesters of 2-cyano-3-oxoalkanoic acids generally in excellent to satisfactory yields. Reaction of methyl 5,5-dimethyl-3-dimethylaminomethylene-2,4-dioxohexanoate with hydroxylamine hydrochloride afforded in moderate yield methyl 4-(2,2-dimethyl-1-oxopropyl)-5-isoxazolecarboxylate, which was converted by acid hydrolysis as above to 4-t-butyl-4-hydroxyfuro[3,4-d]isoxazol-6-(4H)-one.  相似文献   

9.
《合成通讯》2013,43(12):2109-2117
Abstract

The 5-carboxy-1,3-dihydro-1,3-dioxo-2H-isoindole-2-propanoic acid benzyl ester (I), obtained from condensation of 1,3-dihydro-1,3-dioxo-5-isobenzofurancarboxylic acid with β-alanine benzyl ester p-toluenesulfonate, reacted with an appropriate amine (II) to afford the corresponding amide (IIIa–e), which then hydrogenolyzed by 5% palladium-on-carbon to give target compounds (IVa–e).  相似文献   

10.
Conclusions The reaction of substituted 2,5-dioxo-1,2-oxaphospholanes with mercaptans goes to a large degree contrary to the principle of hard and soft acids and bases, with attack of the mercaptan on the carbonyl group.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1722–1726, August, 1971.  相似文献   

11.
A reaction was studied of newly synthesized 1,3-bis(2-hydroxy-3-chloropropyl)uracil and 1,3-bis(2-hydroxy-3-chloropropyl)-6-methyluracil with hydrazine hydrate followed by treating the compounds formed with ethyl acetoacetate. The hydrazones obtained cyclized into pyrazolones in the presence of sodium methylate.  相似文献   

12.
Condensation of several arylhydrazones with chlorocarbonyl phenyl ketene gave 2-(arylmethylidene)-5-oxo-1,4-diphenyl-2,5-dihydro-1H-pyrazol-2-ium-3-olates in high yields.  相似文献   

13.
Based on the structure-activity relationships and antiangiogenic mechanism of RGD-containing peptides,a series of 5-amino- 1,3-dihydro-1,3-dioxo-2H-isoindole derivatives were synthesized.The structures were characterized by ~1H NMR,MS and elementary analysis.There ability to inhibit angiogenesis were evaluated by chick embryo chorioallantoic membrane assay at 10~(-5) mol/L.Compounds 7a and 7b displayed obvious antiangiogenic activity.  相似文献   

14.
15.
Russian Journal of Organic Chemistry - Three-component reaction of methyl 4-aryl-2,4-dioxobutanoates with aromatic aldehyde and 2-aminoacetonitrile sulfate in glacial acetic acid in the presence of...  相似文献   

16.
17.
A synthesis of methyl 2-oxo-5-vinyl-tetrahydrofuran-3-carboxylate involving five synthetic steps from commercially available 3,4-dihydroxybutene is reported.  相似文献   

18.
19.
The title compounds 3a-j together with the N-alkylacylketene S,N-acetals 12a-j were obtained by reaction of N,N'-dialkyldithiodianilines with β-ketoesters compounds. A possible reaction pathway is suggested.  相似文献   

20.
A microscale synthesis (500 mg) of the product 3-[5-anilino-(2,3-d)-dioxole-1,3]-1-oxo-1, 3-dihydro-2-benzofurane (COR.01.126) is described. This method, which requires only four steps, is principally available for the 14C-labeled synthesis with labeled phthalic anhydride as starting material.  相似文献   

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