N. N. Tonkikh
Riga Technical University
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Featured researches published by N. N. Tonkikh.
Chemistry of Heterocyclic Compounds | 2004
N. N. Tonkikh; Andris Strakovs; K. V. Rizhanova; M. V. Petrova
In reactions of 3-(5- and 5,6-substituted 2-aminophenylamino)-5,5-dimethylcyclohex-2-en-ones with carbaldehydes of pyridine, thiophene, and furan and substituted benzaldehydes, we have obtained 21 novel 7H-7-methoxycarbonyl-, 7-benzoyl-, 7-trifluoromethyl-, 7-nitro- and 7,8-dichloro-11-aryl-3,3-dimethyl-1,2,3,4,10,11-hexahydro-5H-dibenzo[b,e]-1,4-diazepin-1-one.
Chemistry of Heterocyclic Compounds | 2004
N. N. Tonkikh; Andris Strakovs; M. V. Petrova
Ten 2,5-dioxo- and 4-aryl-5-oxo-2-thioxo-1,2,3,4,5,6,7,8-octahydroquinazolines have been synthesized in three-component interactions of 1,3-cyclohexanedione or dimedone, urea or thiourea, and substituted benzaldehydes (3-bromo-, 4-bromo-, 4-fluoro-, 4-methoxy-, 3,4-methylenedioxy-, and 3-nitro-). 9-Aryl-4,5-dioxo-1,2,3,4,5,6,7,8-octahydro-9H-xanthenes were also formed in these reactions.
ChemInform | 2002
N. N. Tonkikh; Andris Strakovs; M. V. Petrova; V. V. Chernyshev; H. Schenk
The reaction of 2-aminocarbonyl-5,5-dimethyl-1,3-cyclohexanedione with 2,3-diaminopyridine, 1,2-phenylenediamine (and its 4-methyl, 4-nitro, 4-carboxy, and 4-benzoyl derivatives), and 3,3-diaminobenzidine gave the corresponding 2-[2-(2,3-dihydrobenzimidazolylidene)]- and 2-[2-(2,3-dihydropyrido[2,3-d]imidazolylidene)]-5,5-dimethyl-1,3-cyclohexanediones. Their structure was confirmed by 1H NMR spectroscopic data and X-ray analysis.
Chemistry of Heterocyclic Compounds | 1999
A. I. Gurkovskii; N. N. Tonkikh; M. V. Petrova; A. Ya. Strakov
Reaction of 5,5-dimethyl-2-formylcyclohexane-1,3-dione with 4-methyl-, 4-benzoyl-, and 4-nitro-1,2-diaminobenzenes gave the corresponding 2-(2-amino-4-methylphenylaminomethylene)-, 2-(2-amino-5-benzoylphenylaminomethylene)-, and 2-(2-amino-5-nitrophenylaminomethylene)-5,5-dimethylcyclohexane-1,3-diones. When treated with hydrochloric acid, they cyclize to 7-methyl-, 8-benzoyl-, and 8-nitro-3,3-dimethyl-2,3,4,5-tetrahydro-1H-dibenzo[b,e][1,4]diazepinon hydrochlorides. Under hydrolytic conditions the salts of 3,3,7-trimethyl-2,3,4,5-tetrahydro-1H-dibenzo[b,e][1,4]diazepinone and 3,3-dimethyl-2,3,4,5-tetrahydro-1H-dibenzo[b,e][1,4]diazepinone undergo the C11−N10 bond cleavage to give N-(2-aminophenyl)- and N-(2-amino-5-methylphenyl)-substituted 3-amino-2-formyl-5,5-dimethylcyclohex-2-enones. Ring opening of the hydrochlorides of 8-benzoyl-, and 3,3-dimethyl-8-nitro-2,3,4,5-tetrahydro-1H-dibenzo[b,e][1,4]diazepinones occurs at the C−N5 bond and gives the starting enamines.
Chemistry of Heterocyclic Compounds | 1997
A. Ya. Strakov; M. V. Petrova; N. N. Tonkikh; A. I. Gurkovskii; Yu. Yu. Popelis; G. P. Kreishman; Sergey Belyakov
The reactions of 2-acetyldimedone and 2-acetyl-3-methoxy-5,5-dimethylcyclohex-2-en-1-one with 3,4-diaminobenzophenoneproduce2-[1-(2-amino-5-benzoylphenyl)amino]ethylidene-5,5-dimethyl-1,3-cyclohexanedioneand 2-acetyl-3-(2-amino-5-benzoylphenyl)amino-5,5-dimethylcyclohex-2-en-1-one, which are cyclized by the action of hydrochloric acid, yielding the respective hydrochlorides of 8-benzoyl- and 7-benzoyl-3,3,11-trimethyl-2,3,4,5-tetrahydro-1H-dibenzo[b,e][1,4]diazepin-2-ones. Hydrolytic cleavage of the 8-benzoyl derivative leads to 2-acetyl-3-(2-amino-4-benzoylphenyl)amino-5,5-dimethylcyclohex-2-en-1-one. A similar cleavage to form 2-acetyl-3-(2-aminophenyl)amino-5,5-dimethylcyclohex-2-en-1-one is observed for the known hydrochloride of 3,3,11-trimethyl-2,3,4,5-tetrahydro-1H-dibenzo[b,e][1,4]diazepin-2-one. The structures of the products were confirmed by PMR spectra and x-ray diffraction data.
Chemistry of Heterocyclic Compounds | 2002
Andris Strakovs; N. N. Tonkikh; M. V. Petrova; K. V. Ryzhanova; E. Palitis
The reaction of 2-formyl-1,3-cyclohexanedione, its 5,5-dimethyl, 5-phenyl and 5-(2-furyl) derivatives and of 2-formyl-1,3-indanedione and dehydroacetic acid with histamine, 3-(1-imidazolyl)propylamine, 3-(4-morpholyl)propylamine, 3-(2-pyrrolidon-1-yl)propylamine, 2-(1-piperazinyl)ethylamine, tryptamine, and 2-(aminomethyl)pyridine gave fifteen 2-aminomethylene derivatives. The reaction of these amines with 2-methyl-4-oxo-3,1-benzoxazine gave the 3-substituted 2-methyl-4(3H)-quinazolinones and with 4-oxo-2-phenyl-3,1-benzoxazine the monosubstituted N-benzoylanthranilic acid amides.
Chemistry of Heterocyclic Compounds | 2000
L. G. Delyatitskaya; M. V. Petrova; S. Grinberga; N. N. Tonkikh; A. Ya. Strakov
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.
Chemistry of Heterocyclic Compounds | 2004
N. N. Tonkikh; Andris Strakovs; M. V. Petrova
In reactions of 3-(2-amino-3-pyridyl)amino-5,5-dimethylcyclohex-2-en-1-one with aromatic aldehydes (2- and 4-hydroxy-, 2-hydroxy-3-methoxy-, 4-dimethylamino-, 4-methoxy-, 2,4- and 3,4-dimethoxy-, 3,4-methylenedioxy-, 4-bromo-, 4-fluoro-, 4-chloro-, 2-nitro- and 3-nitrobenzaldehydes, furfural, and 2-thiophenecarbaldehyde), we have obtained the corresponding 10-aryl-7,7-dimethyl-5,6,7,8,9,10-hexahydro-11H-pyrido[3,2-b][1,4]benzodiazepin-9-ones.
Chemistry of Heterocyclic Compounds | 2003
N. N. Tonkikh; K. V. Ryzhanova; M. V. Petrova; Andris Strakovs
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.
Chemistry of Heterocyclic Compounds | 2000
N. N. Tonkikh; A. Ya. Strakov; M. V. Petrova
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.