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1.
Five new compounds, orizaterpenol (1), orizaterpenoid (2), orizaterpenyl benzoate (3), orizanor-diterpenyl benzoate (4), and orizaditerpenyl benzoate (5), along with nine known compounds, were isolated and identified from the rice hulls of Oryza sativa. Their structures were elucidated with the help of different spectroscopic techniques. Orizaterpenol (1) and the known momilactone A (6) and B (7) were found to have cytotoxic effects against P388 murine leukaemia cells, while the other new and known compounds exhibited weak cytotoxicity.__________Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 146–151, March–April, 2005.  相似文献   

2.
Three new compounds, 4-hydroxymethylene-7-(9,9,13-trimethylcyclohexyl)-heptanyl-3′,7′,7′-trimethylcyclohexa-2′,4′-dien-1′-oate (1), 1-(n-hexadec-7-enoxy)-6-(n-octadecanoxy)-β-D-glucopyranoside (2), and (Z)-12-hydroxy-9-octadecenoic acid-12-β-D-glucopyranoside (3), along with the known compound hexacosanoic acid (4), were isolated and identified from the rice hulls of Oryza sativa. Their structures were elucidated by 1D and 2D NMR spectroscopic techniques (1H-1H COSY, 1H-13C HETCOR, DEPT) aided by EIMS, FABMS, HRFABMS, and IR spectra. Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 344–347, July–August, 2007.  相似文献   

3.
Six substances were isolated from the branches and leaves of the Chinese herb Leptopus Chinensis (Bunge) Pojark. by column chromatography for the first time. Their structures were elucidated as 3α-hydroxyfriedelan-2-one, saccharose, triacontanol, friedelane-2α,3β-diols, β-sitosterol-3-O-β-D-glucoside, and β -sitosterol on the basis of x-ray, chemical, and spectroscopic methods. __________ Published in Kimiya Prirodnikh Soedinenii, No. 5, pp. 462–464, September–October, 2005.  相似文献   

4.
The alkylation of 1,6,8-trihydroxy-3-methylanthraquinone (frangula-emodin) by α-bromoalkylmethylketones was investigated. Hydroxyls in the 1-and 8-positions of the β-derivatives were O-acylated. The compositions and structures of the prepared compounds were confirmed by elemental analysis and UV, IR, PMR, and 13C NMR spectroscopy. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 324–326, July–August, 2007.  相似文献   

5.
Short and efficient synthesis of (3R,7R)-hexahydrofarnesyl bromide ((3R,7R)-1-bromo-3,7,11-trimethyldodecane), the terpenoid synthon for the natural α-tocopherol, has been elaborated based on the microwave-activated regioselective enolization of homochiral phytone. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2360–2363, December, 2007.  相似文献   

6.
The dehydration products of driman-8α,11-diol-11-monoacetate that are formed upon reaction with several dehydrating agents and the products from elimination of the C-8 acetoxy group in driman-8α,11-diol diacetate were investigated in detail. A new effective synthesis of drimenylacetate from driman-8α, 11-diol-11-monoacetate by its regioselective dehydration using methanesulfonic acid trimethylsilyl ether was developed. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 340–343, July–August, 2007.  相似文献   

7.
The mixing enthalpies of maltose with several typical α-amino acids (glycine, L-alanine, L-serine, L-valine, L-threonine and L-proline) and dilution enthalpies of each compound have been determined in aqueous solutions at T=298.15 K by a flow-mixing microcalorimeter. The heterotactic enthalpic pairwise interaction coefficients, h xy , of each amino acid with maltose have been calculated by the McMillan–Mayer formalism, and are discussed in terms of intermolecular interactions of the hydrated solute species.  相似文献   

8.
The hetero-Diels-Alder reaction of 3-(N-acetyl-N-benzylamino)-2-formylprop-2-enenitrile with enol ethers yielded cis/trans diastereoisomers of 2-alkoxy-4-amino-3,4-dihydro-2H-pyran-5-carbonitriles in moderate yields. Acidic hydrolysis of cis-diastereoisomer in concentrated sulfuric acid gave 2-oxo-1,2-dihydropyrydine-3-carbaldehyde. The reaction of 2-benzoyl-3-heteroaromaticprop-2-enenitriles with enol ethers afforded diastereoisomeric cis/trans cycloadducts in good yields. The structure of the products is discussed in terms of configuration and preferred conformation. Correspondence: Aleksandra Pałasz, Department of Organic Chemistry, Jagiellonian University, Kraków, Poland.  相似文献   

9.
Summary. The reactions of 5-arylidene derivatives of Meldrum’s acid with ethyl vinyl ether or N-vinyl-2-oxazolidinone yielded trans-trans-(2,4:4,7)-pyrano[4,3-b]pyrans, cis-trans-(2,4:4,7)-pyrano[4,3-b]pyrans, or diastereoisomeric mixtures of pyrano[4,3-b]pyrans and reactions with 3,4-dihydro-2H-pyran afforded Michael adducts. The reactions of 5-arylidene derivatives of Meldrum’s acid with cyanoacetic acid derivatives do not provide appropriate pyrans.  相似文献   

10.
A new method is proposed for the synthesis of indole derivatives containing a chiral substituent at the nitrogen atom, which includes the direct alkylation of indole derivatives with tert-butyl (2S)-(p-tolylsulfonyloxy)propionate, obtained from commercial ethyl (S)-lactate with subsequent conversion to the corresponding p-toluenesulfonyloxy derivative by hydrolysis, and esterification. Dedicated to Academician B. A. Trofimov on his 70th birthday. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, 1391–1398, September, 2008.  相似文献   

11.
A new type of S-containing terpene lactones was produced by the reactions of limonene-1,2-oxide and β-pinene-α-oxide with mercaptoacetic acid. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 220–223, May–June, 2007.  相似文献   

12.
A synthesis is reported for (4R,5R)-and (4S,5S)-4-hydroxymethyl-5-(4-nitrophenyl)oxazolidin-2-ones and (1′R,4R)-and (1′S,4S)-4-[hydroxy(4-nitrophenyl)methyl]oxazolidin-2-ones from (1R,2R)-and (1S,2S)-2-amino-1-(4-nitrophenyl)-1,3-propanediols. The effect of the experimental conditions on the formation of these compounds was studied. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1562–1570, October, 2007.  相似文献   

13.
A new synthetic approach to 4E,7Z-tridecadien-1-ylacetate, a component of the Phthorimaea opercucella (Zeller) potato moth sex pheromone, was developed using a highly stereoselective Claisen rearrangement and Wittig reaction. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 235–236, May–June, 2007.  相似文献   

14.
The chemical composition of the fruits of the north algerian ecotype Pistacia atlantica subsp. atlantica was determined and compared to other fruits of different species in the genus growing in south Algeria and other Mediterranean regions. These fruits were analyzed for their dry matter, protein, crude oil, ash, fatty acids, and phytosterol content. The main fatty acids identified by gas chromatography were oleic (54.15%), linoleic (28.84%), and palmitic (12.21%) acids. The fruits of the north ecotype were found to be rich in protein, oil, fiber, and unsaturated fatty acids, suggesting that they may be valuable for food uses. The sterols isolated were campesterol, stigmasterol, β-sitosterol, and Δ5-avenasterol with β-sitosterol as the major constituent (85%±0.85). The biochemical data indicated an elevated MUFA rate (∼56%) in pistacia oil which may be important against certain pathologies for its nutritional and preventive virtues. Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 103–105, March–April, 2007.  相似文献   

15.
Neutral substances, carbohydrates, and microelements from the aerial part of Silene viridiflora in addition to the protein content and its amino-acid composition were determined. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 365–366, July–August, 2005.  相似文献   

16.
The component composition of essential oils produced by steam distillation from flower heads, leaves, and stems of Salvia anatolica (Lamiaceae), a recently described new species endemic from Turkey, was studied by GC/FID and GC/MS. A total of 127 volatile components representing 96% of the oil was identified in essential oil from flower heads and leaves. It was found that the principal oil components of flower heads and leaves were α-pinene (10.9%), β-pinene (6.7%), α-copaene (6.3%), heptacosane (6.2%), and hexadecanoic acid (5.0%). A total of 109 volatile compounds representing 87.9% of the oil was characterized in essential oil isolated from stems. The principal oil components of stems were identified as hexadecanoic acid (27.2%), tetradecanoic acid (15.2%), dodecanoic acid (5.5%), and α-copaene (5.0%). __________ Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 552–555, November–December, 2007.  相似文献   

17.
A preparative method for the synthesis of first representatives of O,O-diphenyl N-sulfonylbenzimidoylphosphonates was proposed. The method involves oxidation of the corresponding α-(sulfonylamino)benzylphosphonates. The σ-constants of the N-sulfonylbenzimidoylphosphonate group were estimated by 19F NMR spectroscopy. The imidoylphosphonates obtained easily formed stable adducts at the C=N bond with P-and O-nucleophiles. Dedicated to the Corresponding Member of the Russian Academy of Sciences T. A. Mastryukova. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2567–2570, November, 2005.  相似文献   

18.
The geometries of N,N′-diphenylbenzene-1,4-diamine (DPPD), N-phenyl-N′-(1-phenylethyl)benzene-1,4-diamine (SPPD), N-(4-methylpentan-2-yl)-N′-phenylbenzene-1,4-diamine (6PPD), N-propan-2-yl-N′-phenylbenzene-1,4-diamine (IPPD), N-(2-methoxybenzyl)-N′-phenylbenzene-1,4-diamine (MBPPD), and N-phenyl-N′-(2-phenylpropan-2-yl)benzene-1,4-diamine (CPPD) as well as of their dehydrogenation products were optimized by the semiempirical AM1 method. The results support the idea of stable NB=CX structures formation during the consecutive dehydrogenation of SPPD, 6PPD, IPPD, and MBPPD antioxidants. The biradicals formed during the second step of dehydrogenation of substituted phenylenediamines might be important for their antioxidant effectiveness. Dedicated to Professor Vladimír Kvasnička, DrSc., in honour of his 65th birthday  相似文献   

19.
(R, R)-(−)-N, N′-bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediaminocobalt(II) was encapsulated into MCM-22 using the zeolite synthesis method. The encapsulated catalyst proved to be active in the oxidation of α-methylstyrene with NaOCl with higher specific activity than the homogeneous catalyst. At the same time, this encapsulated catalyst was completely inactive in the hydrolytic kinetic resolution of racemic styrene oxide. This observation is in a good correlation with the assumption of the cooperative bimetallic mechanism proposed by Annis and Jacobsen.  相似文献   

20.
Lipids of Eminium Lehmannii leaves and tuber casings and cores were studied. Their class and fatty-acid compositions were determined. Leaf pigments were investigated.__________Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 115–116, March–April, 2005.  相似文献   

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