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1.
The methanol extract of the seeds of Phytolacca americana was reinvestigated to yield three new 1,4-benzodioxane-type compounds, americanoic acid methyl ester (1), isoamericanoic acid A methyl ester (2), and 9'-O-methylamericanol A (3) along with the previously isolated neolignans 6-9. The structures of 1-3 were characterized by 2D NMR and long-range selective proton-decoupling (LSPD) techniques. The neuritogenic effects of compounds 1-3, and dicarboxilic acids 4 and 5, which had been previously synthesized with horseradish peroxidase-catalyzed oxidative coupling of caffeic acid, were examined in primary cultured rat cortical neurons. Americanoic acid A methyl ester (1) exhibited neurite outgrowth-promoting activity at concentration of 0.01-1.0 microM, whereas dicarboxilic acids 4 and 5 were found to induce neuritogenesis dose dependently at the concentrations from 0.1 microM to 10 microM.  相似文献   

2.
A new triterpene glycoside I was isolated together with the five known triterpene glycosides 2-6 from the cultures of Phytolacca americana. The structure of 1 was elucidated by analysis of spectroscopic data and comparison of its NMR data with those of 2-7 and chemical degradation.  相似文献   

3.
The first preparative fractionation of betalain pigments by means of ion-pair high-speed counter-current chromatography (IP-HSCCC) from berry extracts of Phytolacca americana (Phytolaccaceae) is presented. A novel HSCCC solvent system consisting of 1-butanol-acetonitrile-water (5:1:6, v/v/v) was applied using ion-pair forming trifluoroacetic acid at low concentration (0.7%, v/v). Affinity of polar betacyanins and betaxanthins to the organic stationary phase of the biphasic HSCCC solvent mixture was considerably improved. Partitioning coefficient values and influence of increasing trifluoroacetic acid additions to the biphasic solvent mixture were measured for all identified betacyanins and betaxanthins. Gentle separation by IP-HSCCC of the injected pigment extract (900 mg) yielded sufficient amounts of the principal pigments 15S-betanin/15R-isobetanin. The pure epimers separated by C18-HPLC were immediately studied by one- and two-dimensional NMR. In the recovered fractions, minor concentrated betacyanins and betaxanthins were significantly enriched by IP-HSCCC and were detected for the first time in the extracts of P. americana. IP-HSCCC and C18-HPLC were shown to be complementary techniques in the isolation procedure of recovering minor concentrated, highly polar and chemically instable betacyanins and betaxanthin from complex plant matrices. Altogether, identification of 17 betalains was achieved by HPLC-diode array detection-electrospray ionization MS/MS in the HSCCC fractions with their respective isomers, also resulting in the tentative elucidation of betacyanins with novel salicylic acid substitution pattern in the berry extracts of P. americana.  相似文献   

4.
In an effort to establish the relative as well as absolute configuration of the trypanocidally active natural nonadec-6-en-1,2,4-triol isolated from Persea americana, the (2S,4R), (2S,4S), and (2R,4R) isomers were synthesized. The stereogenic centers taken from enantiopure chiral epoxy building blocks derived from inexpensive and readily available D-glucolactone. The (2R,4R) isomer gave (1)H and (13)C NMR as well as specific rotation in excellent consistence with those reported for the natural triol.  相似文献   

5.
From the seeds of Phytolacca americana two new lignans, Americanin B and D, have been isolated and their structures elucidated mainly by spectroscopic methods  相似文献   

6.
7.
He J  Ma J  Lai DW  Zhang YM  Sun WJ 《Natural product research》2011,25(18):1771-1775
A new triterpenoid saponin, named esculentoside T (1), together with five known compounds (2-5), was isolated from the roots of Phytolacca acinosa. The structures of these compounds were elucidated on the basis of spectral data.  相似文献   

8.
Oplodiol, 3-hydroxyepimanool, and epitorulosol have been isolated for the first time from the oleoresin ofPicea ajanensis. On the basis of the results obtained, it may be assumed that the species studied is possibly a hybrid of Yeddo spruce and Siberian spruce.Novosibirsk Institute of Organic Chemistry, Siberian Division of the Russian Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 359–363, May–June, 1994.  相似文献   

9.
10.
Protease A has been isolated in the homogeneous state from dormant seeds of cotton plants of the Tashkent-I variety. A scheme is proposed for the isolation and purification of the enzyme which includes the following stages: extraction of the defatted seeds with 0.1 M phosphate buffer, pH 7.4; precipitation of the protein with ammonium sulfate at 60% saturation; desalting by dialysis; and ionexchange chromatography on a column containing CM- and DEAE-celluloses. The molecular weight of the enzyme has been determined as 60,000. The enzyme efficiently hydrolyzes azocasein and the 7S and 11S reserve proteins of cotton seeds. Its maximum activity appears at pH 6.4–7.4 and a temperature of 35–40°C; it is not activated by sulfhydryl reagents and loses its activity in the presence of diisopropyl phosphorofluoridate. The assumption is made that protease A belongs to the serine type of trypsin-like proteases.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 738–741, November–December, 1986.  相似文献   

11.
From the seeds of Annona glauca and A. cherimola, two novel cyclic peptides, glaucacyclopeptide B and cherimolacyclopeptide G, have been isolated, respectively. Their structures were elucidated by chemical and spectral methods.  相似文献   

12.
Protease A has been isolated in the homogeneous state from dormant seeds of cotton plants of the Tashkent-I variety. A scheme is proposed for the isolation and purification of the enzyme which includes the following stages: extraction of the defatted seeds with 0.1 M phosphate buffer, pH 7.4; precipitation of the protein with ammonium sulfate at 60% saturation; desalting by dialysis; and ionexchange chromatography on a column containing CM- and DEAE-celluloses. The molecular weight of the enzyme has been determined as 60,000. The enzyme efficiently hydrolyzes azocasein and the 7S and 11S reserve proteins of cotton seeds. Its maximum activity appears at pH 6.4–7.4 and a temperature of 35–40°C; it is not activated by sulfhydryl reagents and loses its activity in the presence of diisopropyl phosphorofluoridate. The assumption is made that protease A belongs to the serine type of trypsin-like proteases.  相似文献   

13.
《Tetrahedron》1987,43(8):1775-1784
In addition to reported 17,14-friedo lanostane type (I) of triterpene further triterpenes having new rearranged lanostane skeletons, 17,13-friedo lanostane (II) and 8(14→13R) abeo-17,13-friedo lanostane (III), have been isolated from the seed of Abiesmariesii. The skeletons I and II were also found to occur in A. firma. Their structures have been elucidated by spectral and X-ray diffraction analyses.  相似文献   

14.
15.
Three chromatographically individual fractions, each containing tigogenin glycosides and diosgenin glycosides have been isolated by chromatography on a silica gel column from a methanolic extract of eggplant seeds. To separate the mixture of two difficultly separable glycosides into individual components, each fraction was acetylated and epoxidated, and the derivatives obtained were separated chromatographically. The tigogenin glycoside peracetates isolated were saponified, and the diosgenin epoxide glycoside acetates were de-epoxidated and saponified, to give the individual glycosides, melongosides A, B, E, F, and H. The complete chemical structure of each melongoside has been shown with the aid of acid hydrolysis, methylation, and periodate oxidation followed by a study of the products obtained.Division of Plant Genetics, Academy of Sciences of the Moldavian SSR, Kishinev. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 610–614, September–October, 1984.  相似文献   

16.
Besides the known compounds ( ± ) 3,3-bis-demethylpinoresinol (2), americanol A (3), spergulagenic acid (4), epi-acetylaleuritolic acid (5), 6′-palmityl-α-spinateryl-d-glucoside (6a) and 6′-palmityl-δ7-stigmastenyl-d-glucoside (6b), a novel peltogynoid (1) named icosandrin was obtained from the dried fruits of Phytolacca icosandra. This new compound was characterised by 1D-/2D-NMR, UV, IR and HR-MS techniques as 11ξ-methoxy-6,7-methylenedioxy-[2]benzopyrano-[4,3-b][1]-benzopyran-4-one. Toxicity of 1 was assessed through the Brine Shrimp Lethality Assay. Lignan 2 is reported for the first time in Phytolaccaceae family.  相似文献   

17.
One new triterpenoid saponin orychoside A (1) and one new diterpene glucoside orychoside B (12), together with eleven known compounds, were isolated from the seeds of Orychophragmus violaceus. The structures of the new compounds were elucidated on the basis of spectroscopic analysis. The known compounds were identified by comparison with data reported in the literature. All compounds were tested for their cytotoxic activities against the HepG2 and A549 cell lines in vitro. The new compound 1 exhibited potent cytotoxicity against the two cell lines with IC50 values of 7.13 and 8.77 μM, respectively. Compounds 2, 5, 8 and 9 were found to possess obvious cytotoxicity.  相似文献   

18.
Results are given which confirm the structure of the furostanol glycoside from tomato seeds forming wastes of the preserving industry. From a butanolic extract of the seeds ofLycopersicum esculentum Mill. we have isolated the furostanol glycoside tomatoside A (I) the structure of which has been established as 25(S)-5α-furostan-3β,22α,26-triol 26-O-β-D-glucopyranoside 3-O-[O-β-D-glucopyranosyl-(1→2)-O-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside]. At the same time, by enzymatic and chemical transformations three new spirostanol glycosides of neotigogenin have been obtained: tomatoside B (III), which is 25(S)-5α-spirostan-3β-ol 3-O-[O-β-D-glucopyranosyl-(1→2)-β-D-galactopyranoside], 25(S)-5α-spirostan-3β-ol 3-O-[O-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside] (V), and 25(S)-5α-spirostan-3β-ol 3-O-β-D-galactopyranoside (IV).  相似文献   

19.
20.
As a part of ongoing investigation of Acokanthera oppositifolia (Lam.) Codd., four compounds were isolated from its seeds, a new compound; lup-20(29)-en-3β-O-(3′-β-hydroxy) palmitate (1), three known compounds; a triterpene; lupeol (2), a cardiac glycoside; acovenoside A (3) and a sterol; β-sitosterol (4). Their structures were investigated using 1D & 2D- 1H and 13CNMR spectroscopy. Antimicrobial potential of the compounds was evaluated against 10 microorganisms responsible for endocarditis. The minimum inhibitory concentration (MIC) of the compounds was determined using broth microdilution method. The new compound (1) evidenced significant antibacterial activity especially aganist Pseudomonas aeruginosa with (MIC 7.81 μg/ml). Lupeol (2) exhibited remarkable antimicrobial activity against Methicillin-resistant Staphylococcus aureus, Aspergillus fumigates and Candida albicans (MIC 3.9, 0.24 and 3.9 μg/ml, respectively). On the other hand, acovenoside A (3) inhibited the growth of Escherichia coli (MIC 0.98 μg/ml). We herein present the potential of A. oppositifolia as a cardioprotective agent against the microorganisms responsible for endocarditis.  相似文献   

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