共查询到20条相似文献,搜索用时 46 毫秒
1.
2,2,4-Trichloro-6-phenyl-4,5-dipyrimidinyl, for which nucleophilic substitution with piperdine under various conditions was studied, was obtained from 2,2,4-trioxo-6-phenyl-1, 1,2,2,3,4-hexahydro-4,5-dipyrimidinyl. It is shown that there is an appreciable difference in the rates of substitution of the first, second, and third chlorine atoms, and this made it possible to obtain reaction products that contain one, two, and three piperidino groups. The chlorine atom in the 4 position is replaced initially, after which the chlorine atom in the 2 position undergoes substitution. The structures of the compounds were proved by chemical transformations and analysis of the PMR spectra.See [1] for communication 69.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 821–826, June, 1979. 相似文献
2.
Summary 1. The synthesis of L-(+)--oleoyl--linoleoyl--glycerylphosphorylethanolamine has been effected.2. During the investigations the following substances were isolated and characterized: L--oleoyl--glycerylphosphoryl-N-phthaloylethanolamine and L---linoleoyl--glycerylphosphoryl-N-phthanoylethanolamine.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 2, pp. 80–83, 1966 相似文献
3.
S. A. Medvedeva S. Z. Ivanova N. A. Tyukavkina G. G. Zapesochoya 《Chemistry of Natural Compounds》1978,13(5):539-541
Summary The new C-methylated flavonoid sylpin has been isolated from the needles of the Scotch pine, and the structure of 4,5,6-trihydroxy-3-methoxy-8-methylflavone has been established for it. During the study of the structure of sylpin two new compounds — 4,5,6-triacetoxy-3-methoxy-8-methylflavone and 3,4,5,6-tetrahydroxy-8-methylflavone — were obtained.Irkutsk Institute of Organic Chemistry, Siberian Branch of the Academy of Sciences of the USSR. All-Union Scientific-Research Institute of Medicinal Plants, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 650–653, September–October, 1977. 相似文献
4.
O. I. Gorbyleva T. Ya. Filipenko E. E. Mikhlina K. F. Turchin Yu. N. Sheinker L. N. Yakhontov 《Chemistry of Heterocyclic Compounds》1982,18(6):601-605
The reactions of 2-aryl(hetaryl)methylene-3-oxoquinuclidines with hydrazine hydrate, thiourea, and phenylhydrazine gave, respectively, 7-phenyl-7,7a,dihydropyrazolo[3,4-b]quinuclidine, 7-(4-methoxyphenyl)-7,7a-dihydropyrazolo[3,4-b]quinuclidine, 7-(2-thienyl)-7,7a-dihydropyrazolo-[3,4-b]quinuclidine, 3,3-azinobis (2-benzylidenequinuclidine), 3,3-azinobis[2-(4-methoxybenzylidene)quinuclidine], 6-thio-8-phenyl-5,6,7,8-tetrahydropyrimido[5,4-b]quinuclidine, 2-benzylidene -3-oxoquinuclidine phenylhydrazone, and 2-(4-methoxybenzylidene)-3-oxoquinuclidine phenylhydrazone. The structures of the compounds were confirmed by the IR and 1H and 13C NMR spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 793–797, June, 1982. 相似文献
5.
A. A. Ponomarev I. A. Markushina L. V. Popova 《Chemistry of Heterocyclic Compounds》1967,3(3):325-329
Research on synthesis of polycyclic spirans of the 1, 6-dioxaspiro-[4, 4]nonane group is continued. Electrolysis of methanol solutions of 2-furylcyclopentanol, 2-(5-methyl-furfuryl)cyclopentanol, and 2-furfuryl-1-indanol, gives, by intramolecular alkoxylation, spiro{perhydrocyclopenta[b]furan-2, 2-(5dihydrofuran)}, spiro{perhydrocyclopenta[b]furan-2, 2-(5-methoxy-5-methyl-2, 5-dihydrofuran)}, and spiro{2, 3, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-(5-methoxy-2, 5-dihydrofuran)}, hitherto undescribed in the literature. Depending on the conditions, catalytic hydrogenation of these gives: spiro{perhydiocyclopenta[b]furan-2, 2-(5-methoxytetrahydrofuran)}, spiro{2, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-(5-methoxytetrahydrofuran)}, spiro{perhydrocyclopenta[b]furan-2, 2-tetrahydrofuran}, and spiro{2, 3, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-tetrahydrofuran}.For Part XXXI see [1]. 相似文献
6.
Ya. P. Stradyn L. Ya. Kruminya M. V. Shimanskaya 《Chemistry of Heterocyclic Compounds》1969,5(2):151-155
In aqueous and aqueous-ethanolic buffer solutions at pH<9, 2, 2-bifuryl and 2, 2-furoin give two-electron polarographic electroreduction waves, the half-wave potentials of which depend on the pH. The primary product of the electroreduction of 2, 2-bifuryl is trans-1,2-dihydroxy-1,2-bis(, -furyl)ethylene, which then rearranges into 2, 2-furoin. The anode-cathode wave of 2,2-bifuryl has been studied by means of a Kalousek commutator. It has been shown that the polarographic behavior of 2,2-bifuryl and 2, 2-furoin is similar to that of benzil and benzoin, but differs from the behavior of analogs of the pyridine series. 相似文献
7.
Conclusions A new coumarin, which has been called smyrniodidin, has been isolated from the roots ofSmyrniopsis aucheri acetoxy-1-methylethyl)-4-angeloyloxy-4,5dihydrofuro-2, 3: 7, 6-coumarin. Boiss. The NMR spectrum and a study of the saponification products of smyrnioridin have shown that it is 5-(1- 相似文献
8.
N. E. Ermatov A. I. Ban'kovskii M. E. Perel'son G. P. Syrova Yu. N. Sheinker 《Chemistry of Natural Compounds》1971,4(3):125-128
Conclusions From the roots ofLibanotis buchtormensis (Fisch.) D.C. have been isolated the furocoumarins bergapten, isoimperatorin, a pyranocoumarin, xanthogallol, and a new coumarin buchtormin C19H20O5, for which the structure (+)-3-(,-dimethylacryloxy)-2,2-dimethyl-3, 4-dihydropyrano-5, 6:8, 7-coumarin has been proposed and confirmed by synthesis.Khimiya Prirodnykh Soedinenii, Vol. 4, No. 3, pp. 145–149, 1968 相似文献
9.
Yoshihiro Sugi Yoshihiro Kubota Taka-aki Hanaoka Takehiko Matsuzaki 《Catalysis Surveys from Japan》2001,5(1):43-56
Liquid-phase alkylation of biphenyl (BP) was studied over large-pore zeolites. Selective formation of the least bulky products, 4,4-diisopropylbiphenyl (4,4-DIPB) occurred only in the isopropylation of BP over one- or two-dimensional zeolites, H-mordenite (HM), ZSM-12, SSZ-24, SAPO-5, SSZ-31, and CIT-5. These shape-selective catalyses are ascribed to steric restriction of transition state and to easiness of the substrates to enter into the pores. HM gave the highest selectivity among them. The dealumination of HM enhanced catalytic activity and the selectivity for 4,4-DIPB because of the decrease of coke deposition. Non-regioselective catalysis occurs on external acid sites over HM with the low SiO2/Al2O3 ratio because severe coke deposition deactivates the acid sites inside the pores by blocking pore openings. The selectivity of DIPB isomers was changed with propylene pressure and/or with reaction temperature. Selective formation of 4,4-DIPB was observed at moderate temperatures such as 250°C, whereas the decrease of the selectivity of 4,4-DIPB occurred at higher temperatures as 300°C. 4,4-DIPB yielded selectively under high propylene pressure (<0.3 MPa) at 250°C, while the selectivity of 4,4-DIPB decreased under low propylene pressure as 0.2 MPa. However, 4,4-DIPB was almost exclusive isomer in the encapsulated DIPB isomers inside the pores under every temperature and pressure. The decrease of the selectivity of 4,4-DIPB is due to the isomerization of 4,4-DIPB on the external acid sites. The deactivation of external acid sites of HM was examined by the modification with cerium and other rare earth metal oxide on HM. Selectivities of 4,4-DIPB were improved over modified HM even at high temperatures because of the suppression of non-regioselective alkylation and isomerization at the external acid sites. The ethylation of BP to ethylbiphenyls (EBPs) and diethylbiphenyls (DEBPs) was non-regioselective. The ethylation of BP to EBPs was controlled kinetically. However, there was difference in reactivities of EBPs and DEBPs for their further ethylation. 4-EBP was ethylated preferentially among the isomers, although the formation of 4,4-DEBP was less selective. 4-EBP and 4,4-DEBP have the highest reactivities among EBPs and DEBPs for the ethylation to polyethylbiphenyls (PEBPs). These results show that the environments of HM pores are too loose for shape-selective formation of the least bulky isomers, 4-EBP and 4,4-DEBP, in the ethylation of BP, and that HM pores have enough space for the further ethylation of 4,4-DEBP. 相似文献
10.
M. E. Perel'son V. V. Bandyshev Yu. E. Sklyar K. Vezhkhovska-Renke N. V. Veselovskaya M. G. Pimenov 《Chemistry of Natural Compounds》1977,12(5):533-537
Summary Two new terpenoid coumarins — tadzhiferin (I) and tadzhikorin (II) — have been isolated from the fruit ofFerula tadshikorum M. Pimen.On the basis of physicochemical and spectral investigations, the structure of 7-(9-hydroxy-3,7,11-trimethyldodeca-2,6,10-trienyloxy)coumarin is proposed for (I) and that of 7-(4-acetoxy-9-hydroxy-3,7,11-trimethyldodeca-2,6,10-trienyloxy)coumarin for (II).All-Union Scientific-Research Institute of Medicinal Plants, Moscow. M. V. Lomonosov State University. Botanical Garden, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 593–599, September–October, 1976. 相似文献
11.
Yu. M. Lugovoi N. P. Tarasova G. Bourgeois N. V. Bryantseva V. V. Kostikov C. Filliatre A. G. Shostenko 《Reaction Kinetics and Catalysis Letters》1991,43(1):177-182
The GC-MS method was used to identify the addition products of methyldichlorosilane to vinyl acetate. Radiation-induced addition of methyldichlorosilane to vinyl acetate produces 2-methyldichlorosilylethyl ethyl ether. The reaction follows a radical-chain mechanism. The ratio of the rate constants of methyldichlorosilyl radical addition to C=C and C=O to vinyl acetate amounts to 0.4±0.1 (303 K).
- . , - 2- . , C=C C=O 0,4±0,1.相似文献
12.
Jean-Philippe Demaret Jean-Pierre Ballini Paul Vigny 《Journal of computer-aided molecular design》1993,7(6):683-698
Summary Results of molecular mechanics calculations on intercalation complexes between DNA and angelicin derivatives: angelicin, 4-methylangelicin, 5-methylangllicin, 4,4-dimethylangelicin, 4,5-dimethylangelicin, 4,6,4-trimethylangelicin and 4,6,5-trimethylangelicin, are presented. The correlation between the presence of methyl groups and an increase in DNA photobinding affinity is discussed on the basis of the molecular structures. The influence of the orientation of the angelicins within the intercalation cavity is also discussed. Finally, the consequences of the dynamical behaviour of angelicin in the intercalation cite are studied.Abbreviations CNDO
complete neglect of differential overlap
- NMR
nuclear magnetic resonance
- rms
root mean square
- UV-A
ultraviolet light of class A (320<<400 nm) 相似文献
13.
J. M. Quintela M. C. Veiga R. Alvarez-Sarandés L. González C. Peinador 《Monatshefte für Chemie / Chemical Monthly》1996,127(10):1037-1043
Summary 8,9-Diphenylpyridazino[4,3:4,5]thieno[3,2-d]-1,2,3-triazin-4(3H)-one (2), 3-substituted 8,9-diphenylpyridazino[4,3:4,5]thieno[3,2-d]-1,2,3-triazin-4(3H)-ones (3a–c), 3,4-diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazin-8(7H)-one (4), 8-chloro-3,4-diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazine (5), 8-substituted 3,4-diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazines (6a–h) and 7-substituted 3,4-diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazin-8(7H)-ones(7a–c) were synthesized from 5-amino-3,4-diphenylthieno[2,3-c]pyridazine-6-carboxamide (1).
Synthese neuer Pyridazino[4,3:4,5]thieno[3,2-d]-1,2,3-triazin-und Pyrimido[4,5:4,5]thieno[2,3-c]pyridazin-Derivate
Zusammenfassung Folgende Verbindungen wurden ausgehend von 5-Amino-3,4-diphenylthieno[2,3-c]pyridazin-6-carboxamid (1) synthetisiert: 8,9-Diphenylpyridazino[4,3:4,5]thieno[3,2-d]-1,2,3-triazin-4(3H)-on (2), 3-substituierte 8,9-Diphenylpyridazino[4,3:4,5]thieno[3,2-d]-1,2,3-triazin-4(3H)-one (3a–c), 3,4-Diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazin-8[7H]-on (4), 8-Chlor-3,4-diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazin (5), 8-substituierte 3,4-Diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazine (6a–h) und 7-substituierte 3,4-Diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazin-8(7H)-one (7a–c).相似文献
14.
Convenient methods for the synthesis of chiral 2,3-seco-2-deoxynucleosides were developed. An isopropylidene protective group was used to block the 3,5-hydroxy groups in 2,3-seco-uridine. Conversion of the hydroxymethyl group to a methyl group was accomplished by chlorination with a mixture of CCl4 and Ph3P with subsequent reduction with n-Bu3SnH. 2,3-seco-2-Deoxyuridine was obtained after deacetonation. The (S) enantiomer was similarly synthesized starting from 1-(-D-arabinofuranosyl)uracil. 3-O-tert-Butyldimethylsilyl-5-O-(p-monomethoxytrityl)-2,3-seco-2-deoxyuridine, which has optically active centers at C(1) and C(4), was also synthesized.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 822–826, June, 1988.The authors thank Professor M. Ya. Karpeiskii for his constant interest in this research. 相似文献
15.
A universal key component is proposed for the preparation of oligonucleotides with 3- and 5-terminal phosphate groups — 2,3-dibenzoyluridin-5-yl (4-chlorophenylphosphate) (pU(Bz)2), which is a potential source of the phosphate group. The condensation ofpU(Bz)2 with the 5-OH or the 3-OH group of a protected oligonucleotide leads to the formation of oligodeoxyribonucleotides with 5- or 3-terminal uridine, respectively. The oxidation of the 2,3-cis-glycol group of the terminal uridine unit followed by -elimination forms oligodeoxyribonucleotides with terminal phosphate groups.M. V. Lomonosov Moscow State University. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 731–734, September–October, 1987. 相似文献
16.
E. S. Krongauz V. V. Korshak A. M. Berlin A. P. Travnikova 《Chemistry of Heterocyclic Compounds》1967,3(5):695-698
Heating equimolecular amounts of 1, 1, 2, 2, -tetraacetylethane, 1, 1, 3, 3-tetraacetylpropane, 4, 4-bis(acetoacetyl)diphenyloxide, by and 1, 4-bis(2, 2-diacetoethyl)benzene with 4, 4-dihydrazino-diphenyl gives new thermostable polymers. Some of their characteristics are reported.For Part VII see [2]. 相似文献
17.
Tran Bich Nga V. V. Berentsveig A. P. Rudenko 《Reaction Kinetics and Catalysis Letters》1987,33(2):351-356
Catalytic properties of a mechanical mixture of SiO2-iminodiacetatechromium(III)+V2O5/SiO2 have been studied. A synergetic effect in the combined catalytic oxidation-epoxidation of cyclohexene, observed at about 40 wt.% V2O5, is due to the autocatalytic character of the combined process.
Cr(III), - . 40% . - . , .相似文献
18.
A. Z. Abyshev 《Chemistry of Natural Compounds》1976,10(5):581-585
Summary From a methanolic extract of the roots ofPrangos ferulacea (L) Lindl., growing in the Nakhichevan ASSR, in addition to the compounds found previously, another six substances (I–VI) have been isolated, of which (I) and (VI) have been identified as, respectively, meransin hydrate monoacetate, found for the first time in nature, and umbelliferone: and in the study of a crystalline mixture obtained from the resin of the roots of the plant under investigation collected in Armenia, two coumarins — (VII) and (VIII) — have been isolated.On the basis of a study of IR, NMR, and mass spectra and chemical properties, the structures of the six new cumarin derivatives (II–V, VII, and VIII) have been established. Compound (II) has the structure of 8-(3-methylbutenyloxy)furo-2,3:7,6-coumarin and has been called feruliden; (III) is 7-hydroxy-8-(3-hydroxy-2-senecioyloxyisopentyl) coumarin and has been called ferudiol; (IV) is 7-hydroxy-8-(3-methoxy-2-senecioyloxyisopentyl) coumarin; (V) is 5-[1-(2,3-dihydroxy-3-methylbutyroyloxy)-1-methylethyl]-4,5-dihydrofuro-2,3:7,6-coumarin and has been called lindiol; (VII) is 8-(2-hydroxy-3-methylbut-3-enyloxy)-7-methoxycoumarin and has been called ferudenol; (VIII) is 7-methoxy-8-(3-methyl-2-oxobut-3-enyl)coumarin and has been called prangone.Leningrad Sanitary-Hygenic Medical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 568–574, September–October, 1974. 相似文献
19.
Reactions in solution can be heterogeneously catalyzed not only by conductance or e. m. f. electrodes but also by precipitates formed during the titration of qliquots. Attempts to follow a Menschutkin reaction by Volhard titrations revealed serious errors caused by the catalysis of a side reaction by insoluble silver salts.
, . , .相似文献
20.
V. V. Davydov V. L. Sokol E. V. Balebanova Yu. V. Shklyaev S. V. Sergeev V. A. Nikanorov B. E. Zaitsev M. A. Porai-Koshits 《Russian Chemical Bulletin》1993,42(2):288-294
3,3-Dimethyl- and 3-methyl-1-(4,4-dimethyl-2,6-dioxocyclohex-1-yl)-3,4-dihydroisoquinolines have been synthesized. Crystal and molecular structures of the 3,3-dimethyl derivative have been determined. In the crystalline state this compound exists as a tautomeric form where a hydrogen atom is located at the N atom of the dihydroisoquinoline fragment of the molecule. The tautomeric equilibrium does not shift noticeably in solutions, as shown by IR, UV, and NMR spectroscopy.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 331–336, February, 1993. 相似文献