共查询到20条相似文献,搜索用时 11 毫秒
1.
2.
S. Yu. Kukushkin P. Yu. Ivanov L. M. Alekseeva V. I. Levina K. I. Kobrakov N. B. Grigor'ev V. G. Granik 《Russian Chemical Bulletin》2005,54(8):1887-1891
The half-wave potentials of polarographic reduction of the carbonyl group in unsubstituted and N-methyl- and N-phenylsulfonyl-substituted 1- and 4-oxotetrahydrocarbazoles and their reactivities in reactions with nucleophilic (NaBH4, malonodinitrile, and cyanoacetamide) and electrophilic (DMF dimethyl acetal) reagents were compared. 4-Oxotetrahydrocarbazoles
are much less reactive than 1-oxotetrahydrocarbazoles.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1832–1836, August, 2005. 相似文献
3.
Malose J. Mphahlele Omankutty Gheevarghese Nkosinathi F. H. Makhubela 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):303-314
Abstract O-Mesyloximes derived from 2-aryl-1,2,3,4-tetrahydro-1-methylsulfonyl-4-quinolones react with sodium ethoxide in ethanol to afford the 4-amino-2-arylquinolines in high yield. No traces of the 3-amino-2-aryl-4-quinolones expected from the Neber rearrangement of the substrates were detected or isolated from the reaction mixture. The structures of the products were determined using a combination of 1H NMR, 13C NMR, IR and mass spectroscopic techniques. 相似文献
4.
The Pictet-Spengler reaction with N-protected α-amino aldehydes was found to be very sensitive to reaction conditions. The outcome of the reaction can be controlled mainly by choice of solvent. Tetrahydro-β-carbolines were obtained in apolar solvents, while in polar media octahydro-bipyrroloindoles were the main compounds. Temperature, amount of acid and reaction time also influenced the final results of the PS reaction. Depending on conditions, products with opposite configuration of stereogenic centre, descended from amino aldehydes, were formed as byproducts. 相似文献
5.
Yu. A. Khalilova A. R. Tagirov O. Yu. Doronina L. V. Spirikhin Sh. M. Salikhov F. A. Valeev 《Russian Journal of Organic Chemistry》2014,50(1):110-116
The reactions of levoglucosenone with 2-acetylcyclohexanone and 2-acetyldodecanone occurred as tandem Michael addition and 1: 1 aldol condensation to give the corresponding spiro derivatives. Conditions ensuring 1,2- and 1,4-additions of C5–7, 12-cycloalkanones and enamines derived therefrom to levoglucosenone were found. 相似文献
6.
Vanden Eynden MJ Kunchithapatham K Stambuli JP 《The Journal of organic chemistry》2010,75(24):8542-8549
Calcium bis-1,1,1,3,3,3-hexafluoroisopropoxide is shown to be an effective catalyst for Pictet-Spengler reactions of 3-hydroxyphenethylamine and 3-hydroxy-4-methoxyphenethylamine with various aldehydes and ketones. Previous Lewis acid catalyzed Pictet-Spengler reactions of unactivated ketones typically require two separate reactions (imine formation, cyclization) to obtain the same results. The reactions described within directly provide 1,1'-disubstituted tetrahydroisoquinolines from the corresponding amine and ketone. These rare examples of Pictet-Spengler reactions of unactivated ketones demonstrate the unique nature of calcium as a Lewis acid catalyst. 相似文献
7.
Romualdas Smicius Virginija Jakubkiene Milda M. Burbuliene Povilas Vainilavicius 《Monatshefte für Chemie / Chemical Monthly》2002,133(2):173-181
Summary. Treatment of 5-(6-methyl-2,4-dioxo-1,2,3,4-tetrahydro-3-pyrimidinyl)-methyl-1,3,4-oxadiazole-2-thione with haloalkanes yielded
oxadiazole S-alkyl derivatives, whereas its reaction with formaldehyde and amines resulted in formation of oxadiazole N(3)-aminomethyl
derivatives. The alkylation of 2-alkylsulfanyl-5-(6-methyl-2,4-dioxo-1,2,3,4-tetrahydro-3-pyrimidinyl)-methyl-1,3,4-oxadiazoles
with methyl bromoacetate proceeded at the N(1)-position of pyrimidine to give 2-alkylsulfanyl-5-(1-methoxycarbonylmethyl-6-methyl-2,4-dioxo-1,2,3,4-tetrahydro-3-pyrimidinyl)-methyl-1,3,4-oxadiazoles,
whereas aminomethylation, bromination, or nitration took place at position 5 of pyrimidine ring and afforded the corresponding
5-pyrimidine substituted derivatives.
Received May 9, 2001. Accepted (revised) August 17, 2001 相似文献
8.
以2-溴代-3-甲基环己酮和2-溴代-5-甲基环己酮混合物及2-甲基苯硫酚为原料,经耦合、环化及纯化制得1,2,3,4-四氢-2,6-二甲基二苯并噻吩(3);3在三氟乙酸中经锌粉还原合成了1,2,3,4,4a,9b-六氢-2,6-二甲基二苯并噻吩(4).3和4的结构经1H NMR,13C NMR和GC-MS确证. 相似文献
9.
Z. U. Samarov Z. M. Khakimova R. Okmanov B. Tashkhodzhaev Kh. M. Shakhidoyatov 《Chemistry of Natural Compounds》2008,44(4):480-488
Nitration of deoxypeganine (DOP), deoxyvasicinone (DOV), 2,3-tetramethylene-, 2,3-pentamethylene-, and 3,4-dihydroquinazol-4-ones
and their 1,2-dihydro derivatives was studied. It was shown that the reaction pathway changed depending on the presence of
a carbonyl on C-4 and an N=C bond in these compounds. Only the H atom on C-6 was subject to nitration if both functional groups
were present, for example DOV and its homologs. Substitution of the H atom of either the 6-position (DOP, 1,2-dihydro-DOV,
and their homologs) or the 6- and 8-positions simultaneously (DOP and its homologs) was enhanced if one of these functional
groups was missing depending on the substrate:nitrating agent ratio. The bromination and nitration reactions of 1,2-dihydro-DOV
and its analogs in a 1:2 ratio were accompanied by oxidation of the N1H-CH bond with formation of 6,8-dibromo- and 6,8-nitro-DOV and their homologs. The difference in the behavior of these compounds
was due to the different nucleophilicity of the benzene rings in them. The reaction of 1,2-dihydro-DOV and its homologs with
isocyanates and p-nitro- and p-methylbenzoic acid chlorides was studied. 6-Nitro- and 6,8-dinitro-DOP and 6,8-dibromo- and 6,8-dinitro-DOV and their homologs
and 6-bromo- and 6-nitro-1,2,3,4-tetrahydro-2,3-polymethylenequinazol-4-ones and their 1-alkyl(aryl)-carbamoyl and p-nitro(methyl)-benzoyl derivatives were synthesized. The molecular structures of 1-ethyl-and 1-(o-chlorophenyl)-carbamoyl-1,2-dihydrodeoxyvasicinones and 6,8-dinitro-2,3pentamethylene-3,4-dihydroquinazol-4-one were established.
UDC 547.944/945 547.856.1
Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 387-393, July-August, 2008. Original article submitted May 5, 2008. 相似文献
10.
11.
Several Pd-catalyzed reactions were explored to further functionalize the bromo-substituted 4-amino-1,2,4,5-tetrahydro-2-benzazepin-3-one scaffold (Aba). We report in this paper suitable reaction conditions for Suzuki, Buchwald-Hartwig, and Heck reactions. The substitution pattern of the starting aminobenzazepinone turned out to be crucial for the success of these transition metal-catalyzed reactions, which often required modifications of standard literature procedures. The Pd-catalyzed methods provide access to novel substitution patterns of the Aba scaffold. 相似文献
12.
The Pictet-Spengler reaction of Trp with α-amino aldehydes derived from l and d-amino acids was studied in terms of double stereodifferentiation. The results observed for d-amino aldehydes represent ‘matched’ situation (one diastereoisomer was formed) whereas with l-amino aldehydes ‘mismatched’ (two diastereoisomers were formed). The conformation of newly formed six-membered ring was analyzed. It was found that stable conformers were different for cis and trans isomers. 相似文献
13.
14.
A New Benzylisoquinoline Alkaloid from Sabia parviflora 总被引:1,自引:0,他引:1
A new benzylisoquinoline alkaloid,1,2,3,4-tetrahydro-5-hydroxyl-8-methoxyl-2-methyl-4′-methoxyl-benzylisoquinoline,was isolated from the arial parts of Sabia parviflora. Its structure was established on the basis of spectral analysis. 相似文献
15.
N. Koprivanac Z. Grabarić S. Papić B. S. Grabarić G. Aćamović-Doković 《Monatshefte für Chemie / Chemical Monthly》1995,126(1):23-34
Summary The solution properties ofPPP,QPP, and their complexes with copper and nickel were investigated. The composition and stability of the complexes have been determined using the spectrophotometric method atT=25±1 °C, constant ionic strength (I=0.5M, adjusted with KNO3) and a volume ratio of methanol/water of =0.10 and 0.16 forPPP andQPP, respectively, due to lower solubility ofQPP. The experimental results have been fitted to the theoretical equations using the computerized iterative method of successive approximation. The influence ofpH and addition of another benzene ring to the ligand molecule has been studied. The structures of isolated solid metal complexes withQPP were investigated by infrared and mass spectroscopy. The use ofPPP andQPP as analytical reagents for spectrophotometric determinations of copper and nickel is discussed.
Komplexbildende Eigenschaften vonSchiffschen Basen mit Kupfer- und Nickelionen
Zusammenfassung Die Eigenschaften vonPPP,QPP und ihrer Komplexe mit Kupfer und Nickel in Lösung wurden untersucht. Zusammensetzung und Stabilität der Komplexe wurde bei 25±1 °C, konstanter Ionenstärke (I=0.5M, eingestellt mit KNO3) und einem. Methanol/Wasser-Volumenverhältnis von =0.10 und 0.16 fürPPP bzw.QPP (bedingt durch die geringere Löslichkeit vonQPP) bestimmt. Die experimentellen Ergebnisse wurden mittels eines Algorithmus zur sukzessiven Approximation an die theoretischen Gleichungen angepaßt. Der Einfluß despH-Werts und eines weiteren aromatischen Rings am Liganden wurden studiert. Die Strukturen der isolierten festen Komplexe mitQPP wurden mittels IR- und Massenspektroskopie untersucht. Die Verwendung vonPPP undQPP als analytische Reagenzien zur spektrophotometrischen Bestimmung von Kupfer und Nickel wird diskutiert.相似文献
16.
V. V. Lipson S. M. Desenko V. V. Borodina M. G. Shirobokova O. V. Shishkin R. I. Zubatyuk 《Russian Chemical Bulletin》2006,55(7):1224-1228
A three-component condensation of 3,4,5-triamino-1,2,4-triazole (1) with aromatic aldehydes 2a–f and dimedone (3) or cyclohexanone (8) afforded partially hydrogenated 9-aryl-[1,2,4]triazolo[5,1-b]quinazolin-8-ones. The structure of 2-amino-6,6-dimethyl-3-(4-nitrobenzylidene)amino-9-(4-nitrophenyl)-5,6,7,9-tetrahydro[1,2,4]triazolo[5,1-b]quinazolin-8-one (4e) was confirmed by X-ray diffraction data.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1178–1182, July, 2006. 相似文献
17.
18.
N. N. Tonkikh M. V. Petrova A. F. Mishnev K. V. Ryzhanova F. M. Avotin'sh A. Ya. Strakov 《Chemistry of Heterocyclic Compounds》2000,36(7):822-829
The corresponding 2,3-substituted 4(3H)-quinazolinones were obtained in the reactions of 2-methyl- and 2-phenyl-4-oxo-3,1-benzoxazines with 1-amino-1,2,4-triazole, 4-amino-2,3-dimethyl-1-phenyl-5-pyrazolone, 2-amino-5-ethyl-1,3,4-thiadiazole, 3-amino-6,6-dimethyl-4-oxo-4,5,6,7-tetrahydroindazole, 1-amino-3-cyano-4,6-dimethyl-2-pyridone, and 1-amino-3-cyano-6-phenyl-4-trifluoromethyl-2-pyridone. The formation of N-benzolyanthranilamides in the reactions of 2-phenyl-4-oxo-3,1-benzoxazine with 2-amino-5-ethyl-1,3,4-thiadiazole and 1-amino-3-cyano-6-phenyl-4-trifluoromethyl-2-pyridones was exceptional. The structures of two of the products have been confirmed by X-ray crystallography.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 936–943, July, 2000. 相似文献
19.
20.
S. Z. Vatsadze M. L. Kostochka V. P. Lezina V. G. Vinokurov N. V. Zyk 《Russian Chemical Bulletin》2004,53(12):2805-2809
The reactions of N-substituted piperidin-4-ones with benzylideneacetophenone, resulting in the synthesis of a number of heterocyclic 1,5-dicarbonyl compounds, were studied. 1,2,5-Trimethylpiperidin-4-one enters into cascade-type chalcone addition accompanied by intramolecular aldol condensation giving rise to the 3-azabicyclo[3.3.1]nonane system. The conformations of the 1,5-dicarbonyl compounds and azabicyclononanes synthesized were determined; the regio- and stereochemical features of the reactions of 1,2,5-trimethylpiperidin-4-one with chalcone were studied.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2693–2697, December, 2004. 相似文献