Trifluoroacetylation of ethyl 2,4-dioxopentanoate. The first synthesis of 4-oxo-6-(trifluoromethyl)-4<Emphasis Type="Italic">H</Emphasis>-pyran-2-carboxylic acid and its derivatives

Condensation of ethyl 2,4-dioxopentanoate with ethyl trifluoroacetate in the presence of NaOEt leads to ethyl 4-oxo-6-(trifluoromethyl)-4H-pyran-2-carboxylate, from which the corresponding acid and its amide, as well as 4-hydroxy-6-(trifluoromethyl)pyridine-2-carboxamide were obtained. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 537–538, March, 2007.     

The synthesis of 4-(2,6,10-trimethyl-1,3,5,9-undecatetraenyl)benzoic acid based on alkoxy alkene-acetal condensation

4-(2,6,10-Trimethyl-1,3,5,9-undecatetraenyl)benzoic acid (1) was synthesized starting from ethyl 4-formylbenzoate (2) and linalool. The key intermediate, ethyl 4-(2-methyl-3-oxo-1-propenyl)benzoate (5), was obtained by the addition of diethyl acetal (3), prepared from2, to ethyl 1-propenyl ether (EPE) followed by the hydrolysis of the resulting adduct.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 914–915, May, 1993.     

4-Oxo-3,4-dihydroquinazolinyl- and Benzimidazolylacetonitriles in Annelation Reactions of a Haloquinoline Ring

The interaction of 4-oxo-3,4-dihydroquinazolinyl- and benzimidazolylacetonitriles with 2,6-dihalobenzaldehydes leads to 3-(2,6-dihalophenyl)-2-(4-oxo-3,4-dihydro-2-quinazolinyl)acrylonitriles and 2-(1H-benzo[d]imidazol-2-yl)-3-(2,6-dihalophenyl)acrylonitriles respectively. As a result of intramolecular cyclization of these nitriles 4-halo-12-oxo-12H-quino[2,1-b]quinazoline-6-carbonitriles and 4-halobenzo[4,5]imidazo[1,2-a]quinoline-6-carbonitriles respectively are formed.     

Condensation of Ethyl 2-Oxoindoline-3-glyoxylate with o-Aminophenol and o-Phenylenediamine

A method is presented for the synthesis of 3-(2-oxo-1,2-dihydro-3H-indol-3-ylidene)-1,4-dihydroquinoxalin-2-one and 2-(2-oxo-1,2-dihydro-3H-indol-3-ylidene)-2H-1,4-benzoxazin-3(4H)-one by the reaction of ethyl 2-oxoindoline-2-glyoxylate with o-aminophenol and o-phenylenediamine. Proposed reaction mechanisms are presented.     

An unexpected reaction of 2-vinyloxyethyl isothiocyanate with halocarboxylic acids

Reactions of 2-vinyloxyethyl isothiocyanate with aliphatic halocarboxylic acids give rise to their 1-(2-isothiocyanatoethoxy)ethyl esters in quantitative yields. An unusual rearrangement of 1-(2-isothiocyanatoethoxy)ethyl chloro(bromo)acetate and 3-bromopropanoate to 5-aza-7-chloro(bromo)-4-oxo-3-thiaheptanoic and to 6-aza-8-bromo-5-oxo-4-thiaoctanoic acids, respectively, was observed. Monohalocarboxylic acids and their esters were shown to readily alkylate l,3-oxazolidine-2-thione to form the same thiaheptanoic and thiaoctanoic acids and their esters.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 350–354, February, 1993.     

A Facile Synthesis of Functionalized 1,2,6,7-Tetrahydroimidazo[1,5-c]pyrimidine-3,5-diones

A Pd-mediated hydrogenation of ethyl 6-azidomethyl-1,2,3,4-tetrahydro-4-R-2-oxo-5-pyrimidinecarboxylates leads to the corresponding ethyl 6-aminomethyl1,2,3,4-tetrahydro-4-R-2-oxo-5-pyrimidinecarboxylates. The latter react with bis(trichloromethyl)carbonate, yielding the title ethyl 1,2,3,5,6,7-hexahydro-7-R-3,5-dioxoimidazo[1,5-c]pyrimidine-8-carboxylates.

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Three-component condensation in the synthesis of substituted tetrahydropyridinethiolates

Multicomponent cyclocondensation of Meldrum's acid, 2-chlorobenzaldehyde, and N-(4-bromophenyl)-3-amino-3-thioxopropanamide in the presence of N-methylmorpholine afforded N-methylmorpholinium 3-[N-(4-bromophenyl)carbamoyl]-4-(2-chlorophenyl)-6-oxo-1,4,5,6-tetrahydropyridine-2-thiolate in 65% yield. When treated with dilute HCl, the thiolate easily transformed into N-(4-bromophenyl)-4-(2-chlorophenyl)-2-oxo-6-thioxopiperidine-5-carboxamide, which reacted with alkyl halides to give products of regioselective S-alkylation in high yields. Dedicated to Academician N. K. Kochetkov on the occasion of his 90th birthday. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1297–1298, May, 2005.     

Synthesis and Crystal Structure of Ethyl 2-(6-(1,3-Dioxo-4,5,6,7-tetrahydro-1H-isoindol-2(3H)-yl)-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) Butanoate

The title compound ethyl 2-(6-(1,3-dioxo-4,5,6,7-tetrahydro-1H-isoindol-2(3H)-yl)-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) butanoate 3 was synthesized by the reaction of ethyl 2-(6-amino-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) butanoate with 4,5,6,7-tetraydrophthalic anhydride,and its structure was determined by X-ray single-crystal diffraction.The crystal belongs to the monoclinic system,space group P21/n with a = 9.3469(2),b = 16.7715(5),c = 13.7153(4) ,β = 104.9680(10)°,μ = 0.107 mm-1,Mr = 430.42,V = 2077.08(10) 3,Z = 4,Dc = 1.376 g/cm3,F(000) = 904,T = 296(2) K,R = 0.0508 and wR = 0.1478.     

Synthesis and Crystal Structure of Ethyl 3-（4-Chlorophenyl）-3,4-dihydro-6-methyl-4-oxo-2- （pyrrolidin-1-yl）furo[2,3-d]pyrimidine-5-carboxylate

The crystal structure of the title compound ethyl 3-（4-chlorophenyl）-3,4-dihydro-6- methyl-4-oxo-2-（pyrrolidin-1-yl）furo[2,3-d]pyrimidine-5-carboxylate （C20H20ClN3O4, Mr= 401.84） has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 20.6215（9）, b = 8.5311（4）, c = 21.6886（9） A^°, β = 91.607（1）°, V = 3814.0（3）A^°^3, Z = 8, Dc = 1.400 g/cm^3, F（000） = 1680, μ = 0.233 mm^-1, R = 0.0718 and wR = 0.1545 for 6717 observed reflections with I 〉 2σ（I）. X-ray diffraction analysis reveals two crystallographically independent molecules in the asymmetric unit.     

Synthesis of 2(3)-ethoxycarbonyl-5,6,7,8-tetrafluorochromones

The hitherto unknown ethyl pentafluorobenzoylpiruvate was prepared by condensing pentafluoroacetophenone with diethyl oxalate. Intramolecular cyclization of this ester or of its copper(II) chelate, as well as of ethyl 2-(ethoxymethylene)pentafluorobenzoylacetate affords 2- and 3-ethoxycarbonyl-5,6,7,8-tetrafluorochromones. Hydrolysis of the latter followed by decarboxylation gives 5,6,7,8-tetrafluorochromone.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 362–364, February, 1993.     

4,5-Dihydropyrazolo[3,4-f]quinazolines

By reaction of 6-dimethylamino-5-oxo-2-phenyl-5,6,7,8-tetrahydroquinazoline with hydrazine, phenylhydrazine, 4-bromo-, 4-chlorophenylhydrazines, and also reaction of 6-dimethylaminomethylene-5-oxo-2-(4-pyridyl)-5,6,7,8-tetrahydroquinazoline with hydrazine, 4-methoxy- and 2-carboxyphenylhydrazines, we have obtained the corresponding 7-phenyl(4-pyridyl)-substituted 1H(2H)- or 1-aryl-4,5-dihydropyrazolo[3,4-f]quinazolines. Methylation of 7-phenyl-4,5-dihydro-1(2H)-pyrazolo[3,4-f]quinazoline by methyl iodide led to its 2-methyl derivative.     

A facile synthesis of novel unsymmetrical N-(4-oxo-2-phenyl-3(4H)-quinazolinoyl)-N-(aryl)acetamidines

<正>A series of novel unsymmetrical N-(4-oxo-2-phenyl-3(4H)-quinazolinoyl)-N-(aryl) acetamidines was synthesized by reacting ethyl(1H)-N-(4-oxo-2-phenylquinazolin-3(4H)-y1)ethanimidoate(2) and suitable reactive aromatic amines.Structures' determination of the synthesized compounds was carried out using spectroscopic techniques including IR,~1H NMR,and mass spectrometry. Structural effects on reactivity were also studied.     

3,6,6-trimethyl-4-oxo-1-(2-pyridyl)-4,5,6,7-tetrahydroindazole in Schmidt reaction and Beckmann rearrangement conditions for the 4-hydroxyimino derivative

Treatment of 3,6,6-trimethyl-4-oxo-1-(2-pyridyl)-4,5,6,7-tetrahydroindazole with sodium azide in acids gives 3,7,7-trimethyl-5-oxo-1-(2-pyridyl)-5,6,7,8-tetrahydro(4H)pyrazolo[4,3-b]azepine. Heating 1-(2-pyridyl)-3,6,6-trimethyl- and 1-phenyl-6,6-dimethyl-4-hydroxyimino-4,5,6,7-tetrahydroindazoles in polyphosphoric acid gives 1-phenyl-5,6-dimethyl- and 1-(2-pyridyl)-3,5,6-trimethyl-4-aminoindazole respectively: The reactions of the latter with 4-dimethylaminobenzaldehyde gave the 4-(4-dimethylaminobenzalamino) derivative and with 2-formyldimedone the 4-(4,4-dimethyl-2,6-dioxocyclohexylidenemethylamino) derivative.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 830–834, June, 2000.     

Synthesis of 5-[2-(Phenoxy)ethyl] Derivatives of 6-Methyluracil, 6-Methyl-2-thioxo-2,3-dihydro-1H-pyrimidin-4-one,and 2-Imino-6-methyl-2,3-dihydro-1H-pyrimidin-4-one

A synthesis of novel derivatives of 6-methyluracil, 6-methyl-2-thioxo-, and 2-imino-6-methyl-2,3-dihydro-1H-pyrimidin-4-one containing a 2-(phenoxy)ethyl substituent at position 5 of the pyrimidine ring has been carried out. It was found that 5-[2-(phenoxy)ethyl] derivatives of 6-methyl-2-thioxo- and 2-imino-6-methyl-2,3-dihydro-1H-pyrimidin-4-one are obtained by the condensation of the corresponding ethyl 3-oxo-2-(2-phenoxyethyl)butanoates with thiourea or guanidine. 6-Methyl-5-[2-(phenoxy)ethyl]uracils can be prepared by treating 6-methyl-5-[2-(phenoxy)ethyl]-2-thioxo-2,3-dihydro-1H-pyrimidin-4-ones with an excess of aqueous monochloroacetic acid solution. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1213–1217, August, 2005.     

2-Substituted 5-oxo-5,6,7,8-tetrahydroquinazolines

Twenty novel 2-substituted 5-oxo-5,6,7,8-tetrahydroquinazolines in reactions of 2-formyl-1,3-cyclohexanedione and its 5,5-dimethyl- and 5-phenyl derivatives with 4-chloro- and 4-carbonylaminobenzamidines, 3- and 4-carbamidinopyridines, 2-carbamidinopyrazine, 2-carbamidino-5-trifluoromethylpyridine, 1-carbamidinopyrrolidine, 4-carbamidinomorpholine, and 1-carbamidino-3,5-dimethylpyrazole have been obtained.Riga Technical University, Riga LV-1658, Latvia; e-mail: marina@osi.lv. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 212–26, February, 2000.     

Pyrimido[4,5-f]quinazolines

The corresponding 6-dimethylaminomethylen-5-oxo-5,6,7,8-tetrahydroquinazolines were obtained from reactions of 2-substituted and 2,7-disubstituted 5-oxo-5,6,7,8-tetrahydroquinazolines with the dimethylacetal of DMF. Sixteen 2,8-disubstituted 5,6-dihydropyrimido[4,5-f]quinazolines were obtained from the reaction of 2-phenyl- and 6-(dimethylamino)methylen-5-oxo-2-(4-pyridyl)-5,6,7,8-tetrahydroquinazolines with guanidine and eight amidines. The corresponding 6-hydroxymethylene derivative was obtained by hydrolysis of 6-(dimethylamino)methylen-5-oxo-1-phenyl-5,6,7,8-tetrahydroquinazoline.     

4-甲基-苯磺酸-2-氧-2-[3-(5-芳基-[1,3,4]噁二唑-2-基)-硫脲]-乙基酯的合成及生物活性研究

合成了12个未见文献报道的4-甲基-苯磺酸2-氧-2-[3-(5-芳基-[1,3,4]噁二唑-2-基)-硫脲]-乙基酯, 其结构经元素分析、¹H NMR和IR确证. 初步活性测试结果表明: 部分化合物有较好的杀菌活性.     

Condensations of Ethyl 3-Ethoxy-4-(triphenylphosphoranylidene)-2-butenoate with α,β-Unsaturated Carbonyl Compounds

Summary.  Wittig condensations of α,β-unsaturated carbonyl compounds with ethyl 3-ethoxy-4-(triphenylphosphoranylidene)-2-butenoate gave good to high yields of (2E,4E,6E)-ethyl 3-ethoxy-2,4,6-alkatrienoates. Some of last mentioned compounds were almost quatitatively hydrolysed to (4E,6E)-ethyl 3-oxo-4,6-alkadienoates. This method can therefore be used as an attractive alternative for the preparation of unsaturated conjugated β-keto esters previously prepared in very low yields from α,β-unsaturated carbonyl compounds and ethyl 3-oxo-4-(triphenylphosphoranylidene)butanoate. Present address: Boron Molecular Pty. Ltd., PO Box 756, Noble Park, VIC 3174, Australia. E-mail: cmoorhoff@boronmolecular.com Received June 17, 2002; accepted June 21, 2002     

Synthesis and crystal structure of ethyl 1-benzyl-2-hydroxy-5-methyl-3-oxo-2-phenacyl-2,3-dihydropyrrole-4-carboxylate

Reaction of 5-phenyl-2,3-dihydro-2,3-furandione with ethyl 3-benzylamino-2-butenoate, resulting in ethyl 1-benzyl-2-hydroxy-5-methyl-3-oxo-2-phenacyl-2,3-dihydropyrrole-4-carboxylate and benzylamide ofN-benzoylpyruvic acid, was studied. The structure of the pyrrole derivative was confirmed by X-ray analysis.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1552–1555, August, 1995.     

Synthesis and Crystal Structure of N—tert—butyl—N′—（2，4—dichlorobenzoyl）—N—[1—（4—chlorophenyl）—1,4—dihydro—6—methylpyridazine—4—oxo—3—carbonyl]hydrazine

1 INTRODUCTIONPyridazinone derivatives represent one of the most active classes of compounds possessing a wide spectra of biological activity. They are widely used in pharmaceuticals and agrochemicals[1,2]. Rohm- Haas Company had reported that N-tert-butyl- dibenzoylhydrazine exhibits excellent insecti- cides[3, 4] and t-butyl plays an important role in the insecticide activity [5]. In the previous paper, we had reported that 1-aryl-1,4-dihydro-3- acylhydrazino- carbonyl-4-one-6-methylpy…