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1.
Phytochemical investigation of the galls of Pistacia integerrima Stewart (Pistaceaceae) yielded three new phytoconstituents characterized as n-decan-3′-ol-yl-n-eicosanoate, n-octadecan-9,11-diol-7-one and 3-oxo-9β-lanost-1,20(22)-dien-26-oic acid along with the known compound β-sitosterol. The structures of these phytoconstituents have been elucidated on the basis of spectral data analysis and chemical reactions.  相似文献   

2.
Molar excess volumes, VE, molar excess enthalpies, HE, and speeds of sound data, u, of pyrrolidin-2-one (i) + ethanol or propan-1-ol or propan-2-ol or butan-1-ol (j) binary mixtures have been determined over entire composition range at 308.15 K. The observed speeds of sound data have been utilized to predict excess isentropic compressibilities, of the investigated binary mixtures. The observed excess thermodynamic properties VE, HE and have been analyzed in terms of Graph theory. The analysis of VE data by the Graph theory suggests that pyrrolidin-2-one exists mainly as a mixture of cyclic and open dimer; ethanol as a mixture of dimer and trimer; butan-1-ol and propan-2-ol as mixture of monomer and dimer and propan-1-ol as a dimer in the pure state, and their mixtures contain 1:1 molecular complex. The IR studies lend additional credence to the nature and extent of interactions for the proposed molecular entities in the mixtures. Also, it has been observed that VE, HE and values predicted by the Graph theory compare well to with their corresponding experimental values.  相似文献   

3.
Phytochemical investigation of the aerial parts of Evolvulus alsinoides Linn. (Convolvulacae) resulted in the isolation of a new chromone characterized as 6-hydroxy-5-nonadecanoxychroman-2-one (alsinoideschromone) along with hexatriacontane, octyl octadec-9-enoate, nonyl octadec-9-enoate, dodecanyl-octadec-9,12-dienoate, tetracosanyl hexadec-9-enoate, heptacosan-14-β-ol, stigmast-5, 22-dien-3β-ol and stigmata-5-en-3β-ol. The structure of all these phytoconstituents have been established on the basis of spectral data analysis and chemical reactions.  相似文献   

4.
2-Trifluoromethyl-4H-thiochromene-4-thione obtained from 2-trifluoromethyl-4H-thiochromen-4-one and P2S5 reacts with aromatic amines, hydrazine hydrate, phenylhydrazine, and hydroxylamine at the C(4) atom of the chromene ring to give the corresponding anils, azine, hydrazones, and oxime of thiochromone. 2-Trifluoromethyl-4H-thiochromen-4-one is oxidized by hydrogen peroxide in AcOH into 4-oxo-2-trifluoromethyl-4H-thiochromene 1,1-dioxide and reduced by NaBH4 to 2-trifluoromethyl-4H-thiochromen-4-ol or cis-2-(trifluoromethyl)thiochroman-4-ol. When treated with hydrazine hydrate, thiochromen-4-one gives 3(5)-(2-mercaptophenyl)-5(3)-trifluoromethylpyrazole. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 504–509, March, 2006.  相似文献   

5.
上新世华山松化石中的甾体化合物   总被引:3,自引:0,他引:3  
从上新世华山松(Pliocene Pinus armandii)化石木中分离鉴定了5个甾体成分: 24ξ-n-丙基-胆甾烷-3-酮(1), 豆甾 烷-3-酮(2), 24α-乙基-3α-胆甾醇(3), 4-豆甾烯-3-酮(4)和3β-谷甾醇(5). 化合物1为一个新的C30甾体. 它们的结构由波谱方法鉴定.  相似文献   

6.
Twelve novel constituents isolated from Burley tobacco condensate by semi-preparative GLC. have been identified as (E)-3,4-epoxy-5-isopropyl-nonane-2,8-dione ( A ), exo-(1-methyl-4-isopropyl-7,8-dioxabicyclo[3.2.1]oct-6-yl)methyl ketone ( B ), exo-1-(1-methyl-4-isopropyl-7,8-dioxabicyclo[3.2.1]oct-6-yl)-ethanol ( C ), (E)-5-isopropyl-8-hydroxy-8-methyl-non-6-en-2-one ( D ), (E)-5-isopropyl-6,7-epoxy-8-hydroxy-8-methyl-nonan-2-one ( E ), endo-2-(1-methyl-4-isopropyl-7,8-dioxabicyclo[3.2.1]oct-6-yl)-propan-2-ol ( F ), 3,3,5-trimethyl-8-isopropyl-4,9-dioxabicyclo[3.3.1]nonan-2-ol ( G ), (E)-5-isopropyl-non-3-ene-2,8-diol ( H ), 5-isopropyl-nonane-2,8-diol ( I ), (E)-5-isopropyl-8-hydroxy-non-6-en-2-one ( J ), 5-isopropyl-8-hydroxy-nonan-2-one ( K ), and (E)-3-isopropyl-6-methyl-hepta-4,6-dien-1-ol ( L ). Compounds A–K were synthesized from norsolanadione ( 2 ), and compound L from 2-isopropyl-5-oxo-hexanal ( 15 ). The relative configuration of the bicyclic internal acetals B, C, F, G and their δ-keto-epoxide precursors A and E is discussed. All these Burley tobacco flavour components belong to a growing family of metabolites structurally related to solanone ( 1 ). They are believed to arise from the breakdown of cembrene-type precursors.  相似文献   

7.
Tricyclo[3.2.1.02,7]octan-3-ol ( 1 ) and its 4-isomer 7 were obtained by hydroboration of tricyclo[3.2.1.02,7]oct-3-ene ( 5 ). The former alcohol 1 is quantitatively converted to the isomeric alcohol exo-bicyclo[3.2.1]oct-2-en-7-ol ( 3 ) by treatment with aqueous acid. Photolysis of 1-diazo-3-(cyclopent-3-enyl)-propan-2-one ( 12c ) gave a high yield of tricyclo[3.2.1.03,6]octan-4-one ( 10a ). Reduction of the latter ketone produced a mixture of endo- and exo-tricyclo[3.2.1.03,6]octan-4-ol 2 and 9 , respectively. Oxidation of these secondary alcohols with silver carbonate in benzene furnished a mixture of the ketone 10a and the lactone 14 of 6-hydroxy-bicyclo[2.1.1]heptane-2-carboxylic acid. The latter is thought to be formed by oxydation of the hydrate of the strained ketone 10a .  相似文献   

8.
2,4-Dihydro-5-methyl-2-phenyl-4-(9H-xanthen-9-yl)-3H-pyrazol-3-one ( 3 ) was prepared by the condensation of phenylhydrazine and ethyl α-acetyl-9H-xanthene-9-acetate ( 2 ), or 9H-xanthen-9-ol ( 1 ) and 2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-one ( 4 ). 5-Amino-2,4-dihydro-2-phenyl-4-(9H-xanthen-9-yl)-3H-pyrazol-3-one ( 6 ) was obtained by the condensation of 1 and 5-amino-2,4-dihydro-2-phenyl-3H-pyrazol-3-one ( 5 ).  相似文献   

9.
Synthesis of Optically Active Carotenoids with (R)-4-Hydroxy β-End Groups We describe the synthesis of optically active iso-β-kryptoxanthin ( 12 ; (R)-β,β-caroten-4-ol), iso-α-kryptoxanthins 14 ((4R,6′RS)-β,ε-caroten-4-ol) and 16 ((4R,6′R)-β,ε-caroten-4-ol), 4′-hydroxyechinenone ( 18 ; (R)-4′-hydroxy-β,β-caroten-4-one), and isorubixanthin ( 20 ; (R)-β,ω,-caroten-4-ol), their 400-MHz-1H-NMR spectra, CD spectra and HPLC behaviour.  相似文献   

10.
The densities of propan-1-ol + n-heptane have been measured over the whole composition range at atmospheric pressure and at temperatures from 293 to 318 K using a vibrating tube densimeter. The densities and heat capacities for propan-1-ol + n-heptane mixtures at pressures up to 120 MPa and for temperatures ranging from 293 to 318 K were calculated using the speeds of sound measured under elevated pressures, together with the densities and heat capacities at atmospheric pressure. A modified method, based on the suggestion of Davis and Gordon J. Chem. Phys. 46 (1967), has been applied. The effect of pressure and temperature on the isentropic compressibility, the excess volume, and the excess heat capacity are discussed.  相似文献   

11.
The present investigation describe the synthesis of 8-(benzyloxy)-5-(2-[1,3-diphenyl-1H-pyrazol-4-yl]thiazol-4-yl)quinolin-2(1H)-one derivatives. Quinolin-8-ol was transformed by five step synthetic procedures into 8-Benzyloxy-5-(2-bromo-acetyl)-1H-quinolin-2-one. Subsequently, 8-Benzyloxy-5-(2-bromo-acetyl)-1H-quinolin-2-one condensed with 1,3-Diphenyl-1H-pyrazole-4-carbothioic acid amide in the presence of acetonitrile to afford 8-(benzyloxy)-5-(2-[1,3-diphenyl-1H-pyrazol-4-yl]thiazol-4-yl)quinolin-2(1H)-one derivatives. Synthesized compounds were screened for their antimicrobial activity against gram-positive and gram-negative bacteria. Most of the synthesized compounds are found to be active against tested bacterial strains and fungal strain.  相似文献   

12.
Identification of short side chain sterols in the sponge Damiriana hawaiiana The steroidal composition of the sponge Damiriana hawaiiana is examined. Twenty-seven components are identified. In addition to the C26-C29, Δ5-mono and diunsaturated sterols, the sponge contains sterols without side-chain: androsta-5, 16-dien-3β-ol( 1 ), androst-5-en-3β-ol( 2 ); sterols with a non-functionalized side-chain consisting of two, three, four, five and six carbon atoms: pregna-5, 20-dien-3β-ol( 5 ), pregn-5-en-3β-ol( 6 ), 23, 24-bisnor-chola-5, 20-dien-3β-ol( 7 ), 23, 24-bisnor-chol-5-en-3β-ol( 8 ), 24-nor-chol-5-en-3β-ol( 10 ), chol-5-en-3β-ol( 11 ), 26, 27-bisnor-cholest-5-en-3β-ol( 12 ), and sterols possessing a short oxygenated side-chain such as 3β-hydroxy-androst-5-en-17-one( 3 ), androst-5-en-3β, 17β-diol( 4 ) and 3β-hydroxy-26, 27-bisnor-22-trans-cholesta-5, 22-dien-24-one( 14 ). The probable biological or dietary origin rather than artifact production of these hitherto undescribed components from marine sources is supported by their relatively high concentration and their relative proportions, both very different from those expected for autoxidation.  相似文献   

13.
Densities, ρ, of the binary systems {difurylmethane + (ethanol or propan-1-ol or butan-1-ol or pentan-1-ol or hexan-1-ol)} have been measured with an Anton Paar DMA 4500 vibrating-tube densimeter over the entire composition range at 288.15 and 308.15 K and atmospheric pressure. The measured and literature densities of [difurylmethane + n-alkanol] binary systems have been used to check the validity of the relationship describing the dependence of density on composition. This relation is useful for obtaining interpolated ρ values corresponding to the experimental data. Excess molar volumes (V mE) of each mixture, limiting (V m,i E,∞) and excess partial (V m,i E) molar volumes and the limiting partial molar expansion (E p,i ) of both components of each binary system have been examined to provide insight into the temperature variations of the intermolecular interactions and molecular packing efficiencies. The results have been discussed in terms of specific intermolecular interactions and structural effects.  相似文献   

14.
The acetylenic diol 2 , prepared by reaction of but-3-yn-2-ol dianion with 2,6,6-trimethyl-4,4-ethylenedioxy-cyclohex-2-en-1-one ( 1 ), afforded 3,5,5-trimethyl-4-(2-butenylidene)-cyclohex-2-en-1-one ( 4 ), a major constituent of Burley tobacco flavour, upon LiAlH4 reduction and hydrolysis. Vomifoliol ( 5 ) and blumenol C ( 6 ) were major by-products in this reaction.  相似文献   

15.
Phytochemical investigation of the methanolic extract of the seeds of Butea monosperma (Lam.) Taub. (Fabaceae) led to the isolation of three higher fatty acids, viz., n-docosanoic, n-octacosanoic, and n-dotriacontanoic acids, together with /-sitosterol xyloside and a zingiberene diglucoside, characterized as 3,4-dihydrozingiberen-14-ol-β-D-glucopyranosyl-(1→4)-/-D-glucopyranoside. All these phytoconstituents were reported from the seeds of B. monosperma for the first time and their structures were established on the basis of spectral data analysis and chemical reactions.  相似文献   

16.
20, 21-Aziridine Steroids: Reaction of Derivatives of the Oximes of 5-Pregnen-20-one, 9β, 10α-5-Pregnen-20-one and 9β, 10α-5,7-Pregnadiene-20-one with Lithium Aluminium Hydride, and of 3β-Hydroxy-5-pregnen-20-one Oxime with Grignard Reagents. Reduction of 3β-hydroxy-5-pregnen-20-one oxime ( 2 ) with LiAlH4 in tetrahydrofuran yielded 20α-amino-5-pregnen-3β-ol ( 1 ), 20β-amino-5-pregnen-3β-ol ( 3 ), 20β, 21-imino-5-pregnen-3β-ol ( 6 ) and 20β, 21-imino-5-pregnen-3β-ol ( 9 ). The aziridines 6 and 9 were separated via the acetyl derivatives 7 and 10 . The reaction of 6 and 9 with CS2 gave 5-(3β-hydroxy-5-androsten-17β-yl)-thiazolidine-2-thione ( 8 ). Treatment of the 20-oximes 12 and 15 of the corresponding 9β,10α(retro)-pregnane derivatives with LiAlH4 gave the aziridines 13 and 16 , respectively. Their deamination led to the diene 14 and triene 17 , respectively. Reduction of isobutyl methyl ketone-oxime with LiAlH4 in tetrahydrofuran yielded 2-amino-4-methyl-pentane ( 19 ) as main product, 1, 2-imino-4-methyl-pentane ( 22 ) as second product and the epimeric 2,3-imino-4-methyl-pentanes 20 and 21 as minor products. – 3β-Hydroxy-5-pregnen-20-one oxime ( 2 ) was transformed by methylmagnesium iodide in toluene to 20α, 21-imino-20-methyl-5-pregnen-3β-ol ( 23 ) and 20β, 21-imino-20-methyl-5-pregnen-3β-ol ( 26 ). Acetylation of these aziridines was accompanied by elimination reactions leading to 3β-acetoxy-20-methylidene-21-N-acetylamino-5-pregnene ( 30 ) and 3β-acetoxy-20-methyl-21-N-acetylamino-5,17-pregnadiene ( 32 ). The reaction of oxime 2 with ethylmagnesium bromide in toluene gave 20α, 21-imino-20-ethyl-5-pregnen-3β-ol ( 24 ) and 20α,21-imino-20-ethyl-5-pregnen-3β-ol ( 27 ). Acetylation of 24 and 27 led to 3β-acetoxy-20-ethylidene-21-N-acetylamino-5-pregnene ( 31 ), 3β-acetoxy-20-ethyl-21-N-acetylamino-5,17-pregnadiene 33 and 3β, 20-diacetoxy-20-ethyl-21-N-acetylamino-5-pregnene ( 37 ). With phenylmagnesium bromide in toluene the oxime 2 was transformed to 20β, 21-imino-20-phenyl-5-pregnen-3β-ol ( 25 ) and 20β,21-imino-20-phenyl-5-pregnen-3β-ol ( 28 ). Acetylation of 25 and 28 yielded 3β-acetoxy-20-phenyl-21-N-acetylamino-5, 17-pregnadiene ( 34 ) and 3β,20-diacetoxy-20-phenyl-21-N-acetylamino-5-pregnene ( 39 ). LiAlH4-reduction of 39 gave 3β, 20-dihydroxy-20-phenyl-21-N-ethylamino-5-pregnene ( 41 ). – The 20, 21-aziridines are stable to LiAlH4. Consequently they are no intermediates in the formation of the 20-amino derivatives obtained from the oxime 2 .  相似文献   

17.
The reaction of perfluoro(1-methyl-1-phenyl-1,2-dihydrocyclobutabenzene) with SbF5 at 50°C, followed by hydrolysis, gave perfluoro(1-phenylindan-1-ol), while analogous reaction at 90°C afforded perfluoro[10-methylanthracen-9(10H)-one]. Perfluoro(1-methyl-2-phenyl-1,2-dihydrocyclobutabenzene) did not undergo skeletal transformations under analogous conditions, whereas at 200°C it was converted mainly into perfluoro(9-methylfluoren-9-ol). Perfluoro(1-ethyl-2-phenyl-1,2-dihydrocyclobutabenzene) reacted with SbF5 at 200°C to form perfluoro(9-ethylfluoren-9-ol) together with perfluorinated 9,9-dimethyl- and 9-ethyl-9-methyl-1,2,3,4-tetrahydro-9H-fluorenes.  相似文献   

18.
trans-2,3-Dihydro-3-hydroxy-2-phenyl-4H-l-benzopyran-4-one (trans-flavanon-3-ol) was resolved to acetate of (2S,3S)-(-)-trans-flavanon-3-ol and (2R,3R)-(-)-trans-flavanon-3-ol by an enzymatic transesterification with vinyl acetate in the presence of Pseudomonas cepacia lipase.  相似文献   

19.
Alkylation of (1R,2R,5R)-2-benzenesulfonyl-6,8-dioxa-bicyclo[3.2.1]octan-3-one, which is accessible from levoglucosan, afforded (1R,2R,5R)-2-benzenesylfonyl-2,4,4-trimethyl-6,8-dioxabicyclo[3.2.1]octan-3-one. This was further converted into (1S,2R,3S,5R)-2,4,4-trimethyl-6,8-dioxabicyclo[3.2.1]octan-3-ol representing the C9—C13 fragment of acutiphycin molecule.  相似文献   

20.
1,3-Dipolar cycloaddition of nitrile oxides to 5,5,6-trimethyl-exo-2-ethynylbicyclo[2.2.1]heptan-endo-2-ol yields the corresponding 2-(isoxazol-5-yl) derivatives. Opening of the isoxazole ring in the latter gives rise to prostanoid precursors with partially built up or completed side chain. 5,5,6-Trimethyl-3-methylenebicyclo[2.2.1]heptan-2-one reacts with nitromethane in the presence of tetramethylguanidine to afford 5,5,6-trimethyl-exo-3-(2-nitroethyl)bicyclo[2.2.1]heptan-2-one which can be converted into the corresponding nitrile oxide by the action of phenyl isocyanate in benzene in the presence of triethylamine as catalyst. 1,3-Dipolar cycloaddition of the nitrile oxide to ethyl 4-pentynoate yields 3-exo-[5-(2-ethoxycarbonylethyl)isoxazol-3-ylmethyl]-5,5,6-trimethylbicyclo[2.2.1]heptan-2-one. Treatment of the latter with hydroxyl amine leads to formation of the corresponding Z-oxime whose reaction with n-hexyl bromide results in transalkylation of the ester group to afford 3-exo-[5-(2-hexyloxycarbonylethyl)isoxazol-3-ylmethyl]-5,5,6-trimethylbicyclo[2.2.1]heptan-2-one oxime.  相似文献   

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