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111.
A study was carried out on the nucleophilic cyclotransformation of pyrrolo[1,2-a]pyrazinium salts and isoquinolinium salts
containing a methyl group in the α-position. A method for the preparation of alkylaminotetrahydroindolizinones and tetralones
was proposed.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1551–1557, October, 2005. 相似文献
112.
113.
Zhang Z Leitch DC Lu M Patrick BO Schafer LL 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(7):2012-2022
Amidate-supported titanium amido complexes are efficient and regioselective precatalysts for intermolecular hydroamination of terminal alkynes with primary amines. The synthesis and characterization of the first bis(amidate)-supported titanium-imido complex is reported. Its role as the active catalytic species is suggested in the course of product distribution studies using deuterated substrates. The bis(amidate)-supported precatalysts exhibit good functional-group tolerance, even performing hydroaminations in the presence of ester and amide groups. This functional-group tolerance was exploited in the synthesis of a variety of 1-substituted tetrahydroisoquinoline alkaloids and a one-pot hydroaminative procedure for the high yielding preparation of the benzo[a]quinolizine skeleton. 相似文献
114.
V. A. Glushkov Yu. V. Shklyaev O. A. Maiorova G. A. Postanogova E. V. Feshina 《Chemistry of Heterocyclic Compounds》2000,36(3):319-325
Substituted 3-trifluoromethyl-5,6-dihydro-1,2,4-triazolo[3,4-a]isoquinolines were obtained by the reaction of substituted 1-methylthio-3,4-dihydroisoquinolines with hydrazine hydrate and trifluoroacetic acid. The corresponding 3-perfluoroalkyl derivatives are formed in the course of dehydration of 2-(3,3-dimethyl-3,4-dihydro-1-isoquinolyl)hydrazides of perfluorocarboxylic acids.Institute of Technical Chemistry, Ural Branch, Russian Academy of Sciences, Perm. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 380–386, March, 2000. 相似文献
115.
《Magnetic resonance in chemistry : MRC》2002,40(11):687-692
Continuing our systematic 15N NMR study of isoquinoline alkaloids, we report a contribution extending our previous paper. The 15N NMR chemical shifts and 15N,1H long‐range coupling pathways of tertiary and quaternary isoquinoline alkaloids of several constitutional types are presented. The selected compounds belong to the protoberberine, proaporphine, pavinane, rhoeadine and phtalideisoquinoline classes of alkaloids and were investigated by gradient‐selected inverse‐detected multiple bond correlation experiments (GHMBC and GSQMBC). In addition, x‐ray data and the principal geometric parameters of stylopine, mecambridine, norchelerythrine, isothebaine and mecambrine are reported and discussed. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
116.
The anisotropic effects of the phenyl, α- and β-naphthyl moieties in four series of 1,3-oxazino[4,3-a]isoquinolines on the 1H chemical shifts of the isoquinoline protons were calculated by employing the Nucleus Independent Chemical Shift (NICS) concept and visualized as anisotropic cones by a through-space NMR shielding grid. The signs and extents of these spatial effects on the 1H chemical shifts of the isoquinoline protons were compared with the experimental 1H NMR spectra. The differences between the experimental δ (1H)/ppm values and the calculated anisotropic effects of the aromatic moieties are discussed in terms of the steric compression that occurs in the compounds studied. 相似文献
117.
Benzo[a]quinolizines (pyrido[2,1-a]isoquinolines) were synthesized via heterocyclization of 1-alkyldihydroisoquinoline Schiff bases with -ketoesters. 相似文献
118.
119.
S. L. Bogza S. Yu. Suikov N. M. Bogdan Yu. A. Nikolyukin V. I. Dulenko 《Chemistry of Heterocyclic Compounds》2004,40(11):1421-1426
The recyclization reactions of 4-cyanobenzo[c]pyrylium salts with ammonia, primary amines, and hydrazines have been studied. New derivatives of isoquinoline, benzo-2,3-diazepine, and pyrazolo-[ 5,4-c]isoquinoline have been obtained.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1645–1651, November, 2004. 相似文献
120.
X. J. Liu H. L. Zhang Z. -C. Tan K. L. Han L. X. Sun 《Journal of Thermal Analysis and Calorimetry》2007,89(3):907-911
The isoquinoline alkaloids were isolated from traditional Chinese drugs of Phellodendri Cortex, Radix Stephaniae Tetrandrae,
Corydalis Yanhusuo and Corydalis Bungeana. The power-time curves of growth of E. coli at different concentrations of isoquinoline alkaloid at 37°C were determined by a 2277 Thermal Activity Monitor. The rate
constant of bacteriostastic activity was calculated. The relationship between growth rate constant and concentration was established.
The optimum bacteriostastic concentration was determined. Experimental results have indicated that all the isoquinoline alkaloids
isolated from the four kinds of traditional Chinese drugs have bacteriostastic activity and the order is Phellodendri Cortex>Radix
Stephaniae Tetrandrae>Corydalis Yanhusuo>Corydalis Bungeana. 相似文献