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1.
Bioassay-guided fractionation of EtOH extract of the roots of Scrophularia ningpoensis Hemsl. resulted in the isolation of three new iridoid glycosides, i.e., 6'-O-caffeoylharpagide (1), 6'-O-feruloylharpagide (2), and 6'-O-beta-glucopyranosylharpagoside (3), and five new aromatic glycosides, i.e., 2-(3-hydroxy-4-methoxyphenyl)ethyl O-alpha-arabinopyranosyl-(1-->6)-O-alpha-rhamnopyranosyl-(1-->3)-O-beta-glucopyranoside (4), phenyl O-beta-xylopyranosyl-(1-->6)-O-beta-glucopyranoside (5), 3-methylphenyl O-beta-xylopyranosyl-(1-->6)-O-beta-glucopyranoside (6), 6-O-cinnamoyl beta-fructofuranosyl-(2-->1)-O-alpha-glucopyranosyl-(6-->1)-O-alpha-glucopyranoside (7), and 6-O-feruloyl beta-fructofuranosyl-(2-->1)-O-alpha-glucopyranosyl-(6-->1)-O-alpha-glucopyranoside (8), together with four known compounds, i.e., 6'-O-alpha-D-galactopyranosyl harpagoside (9), 6'-O-(p-coumaroyl) harpagide (10), harpagoside (11), and angoroside C (12). Activity of the isolated compounds on [Ca2+](i) increase induced by KCl was evaluated on rat cardiac myocytes using confocal laser scanning microscopy. Iridoid glycosides 1, 10, and 11, and aromatic glycosides 5 and 6 significantly inhibited the increase of [Ca2+](i) induced by KCl at 100 microM.  相似文献   

2.
Three positional isomers of 6(I),6(n)-di-O-(beta-L-fucopyranosyl)-cyclomaltoheptaose [6(I),6(n)-di-O-(beta-L-Fuc)-beta-cyclodextrin, -betaCD, n=II-IV] were chemically synthesized using the corresponding authentic compounds, 6(I),6(n)-di-O-(tert-butyldimethylsilyl)-betaCD (n=II-IV), as the fucosyl acceptors, and 2,3,4-tri-O-acetyl-L-fucopyranosyl trichloroacetimidate as the fucosyl donor. Their structures were analyzed by HPLC, MS, and NMR spectroscopy. The hemolytic activities of L-Fuc-betaCDs were lower than that of betaCD, while the solubilities of these branched CDs in water were much higher than that of betaCD. The molecular interaction between these compounds and the fucose-binding lectin Aleuria aurantia lectin (AAL) was investigated using an optical biosensor based on a surface plasmon resonance (SPR) technique. The order of binding affinity, as a function of the fucose-binding position, was 6(I),6(IV)->6(I),6(III)->6(I),6(II)-di-O-(beta-L-Fuc)-betaCD>6-O-(beta-L-Fuc)-betaCD.  相似文献   

3.
Acylated flavone C-glycosides from Cucumis sativus   总被引:3,自引:0,他引:3  
Leaves of Cucumis sativus plants treated with silicon and infected with Sphaerotheca fuliginea yielded five new acylated flavone C-glycosides identified as isovitexin 2"-O-(6"'-(E)-p-coumaroyl)glucoside (6), isovitexin 2"-O-(6"'-(E)-p-coumaroyl)glucoside-4'-O-glucoside (7), isovitexin 2"-O-(6"'-(E)-feruloyl)glucoside-4'-O-glucoside (11), isoscoparin 2"-O-(6"'-(E)-p-coumaroyl)glucoside (9), and isoscoparin 2"-O-(6"'-(E)-feruloyl)glucoside-4'-O-glucoside (12). The known flavone-glycosides isovitexin (1), saponarin (2), saponarin 4'-O-glucoside (3), vicenin-2 (4), apigenin 7-O-(6"-O-p-coumaroylglucoside) (5), isovitexin 2"-O-(6"'-(E)-feruloyl)glucoside (8) and isoscoparin 2"-O-(6"'-(E)-feruloyl)glucoside (10), were also identified in this plant material.  相似文献   

4.
We compared the polyunsaturated fatty acid (PUFA) status of Dutch vegans and omnivores to investigate whether disparities can be explained by different diets and long chain PUFA (LCP) synthesis rates. Dietary intakes and fatty acid compositions of erythrocytes (RBC), platelets (PLT), plasma cholesterol esters (CE) and plasma triglycerides (TG) of 12 strict vegans and 15 age- and sex-matched omnivores were determined. Vegans had higher omega 6 (CE, TG), 18:2 omega 6 (RBC, CE, TG), 18:3 omega 6 (TG), 20:3 omega 6 (TG), 22:4 omega 6 (TG), 22:5 omega 3 (RBC, PLT), 22:5 omega 3/22:6 omega 3 (RBC, PLT) and 22:5 omega 6/22:6 omega 3 (RBC, PLT), and lower 22:4 omega 6 (RBC, PLT), 22:4 omega 6/22:5 omega 6 (RBC, PLT), omega 3 (CE), LCP omega 3 (CE, TG), 20:5 omega 3 (RBC, PLT, CE), 22:5 omega 3 (TG) and 22:6 omega 3 (all compartments). Vegans had lower 20:4 omega 6 (TG) after normalization of PUFA to 100%, and normalization of eicosanoid precursors to 100% revealed similar 20:4 omega 6 (all), higher 20:3 omega 6 (TG) and lower 20:5 omega 3 (all). High omega 6 (notably 18:2 omega 6) and low omega 3 (notably 20:5 omega 3, 22:6 omega 3) status in Dutch vegans derives from low dietary LCP omega 3 and 18:3 omega 3/18:2 omega 6 ratio. Higher 18:3 omega 6 and 20:3 omega 6 in their TG may reflect higher hepatic 20:4 omega 6 production rate, whereas higher 20:4 omega 6 and 22:4 omega 6 in omnivores indicates 20:4 omega 6 intake from meat.  相似文献   

5.
In this work, we have purified the His-tagged oxygenase (ht-oxygenase) component of Rhodococcus globerulus P6 biphenyl dioxygenase. The alpha or beta subunit of P6 oxygenase was exchanged with the corresponding subunit of Pseudomonas sp. strain LB400 or of Comamonas testosteroni B-356 to create new chimeras that were purified ht-proteins and designated ht-alpha(P6)beta(P6), ht-alpha(P6)beta(LB400), ht-alpha(P6)beta(B-356), ht-alpha(LB400)beta(P6), and ht-alpha(B-356)beta(P6). ht-alpha(P6)beta(P6), ht-alpha(P6)beta(LB400), ht-alpha(P6)beta(B-356) were not expressed active in recombinant Escherichia coli cells carrying P6 bphA1 and bphA2, P6 bphA1 and LB400 bphE, or P6 bphA1 and B-356 bphE because the [2Fe-2S] Rieske cluster of P6 oxygenase alpha subunit was not assembled correctly in these clones. On the other hand ht-alpha(LB400)beta(P6) and ht-alpha(B-356)beta(P6) were produced active in E. coli. Furthermore, active purified ht-alpha(P6)beta(P6), ht-alpha(P6)beta(LB400), ht-alpha(P6)beta(B-356), showing typical spectra for Rieske-type proteins, were obtained from Pseudomonas putida KT2440 carrying constructions derived from the new shuttle E. coli-Pseudomonas vector pEP31, designed to produce ht-proteins in Pseudomonas. Analysis of the substrate selectivity pattern of these purified chimeras toward selected chlorobiphenyls indicate that the catalytic capacity of hybrid enzymes comprised of an alpha and a beta subunit recruited from distinct biphenyl dioxygenases is not determined specifically by either one of the two subunits.  相似文献   

6.
Physical maps of the genome of Moloney murine leukemia virus (M-MLV) DNA were constructed by using bacterial restriction endonucleases. The in vitro-synthesized M-MLV double-stranded DNA was used as the source of the viral DNA. Restriction endonucleases Sal I and Hind III cleave viral DNA at only one site and, thus, generate two DNA fragments. The two DNA fragments generated by Sal I are Sal IA (molecular weight, 3.5 x 10(6)) and Sal IB (molecular weight, 2.4 x 10(6)) and by Hind III are Hind IIIA (molecular weight, 3.6 x 10(6) and Hind IIIB (molecular weight, 2.3 x 10(6)). Restriction endonuclease Bam I generates four fragments of molecular weights of 2.1 x 10(6) (Bam IA), 2 X 10(6) (Bam IB), 1.25 X 10(6) (Bam IC), and 0.24 x 10(6) (Bam ID), whereas restriction endonuclease Hpa I cleaves the M-MLV double-stranded DNA twice to give three fragments of molecular weights of 4.4 x 10(6) (Hpa IA), 0.84 X 10(6) (Hpa IB), and 0.74 x 10(6) (Hpa IC). Digestion of M-MLV double-stranded DNA with restriction endonuclease Sma I produces four fragments of molecular weights of 3.9 x 10(6) (Sma IA), 1.3 X 10(6) (Sma IB), 0.28 X 10(6) (Sma IC), and 0.21 x 10(6) (Sma ID). A mixture of restriction endonucleases Bgl I and Bgl II (Bgl I + II) cleaves the viral DNA at four sites generating five fragments of approximate molecular weights of 2 x 10(6) (Bgl + IIA), 1.75 X 10(6) (Bgl I + IIB), 1.25 X 10(6) (Bgl I + IIC), 0.40 X 10(6) (Bgl I + IID), and 0.31 x 10(6) (Bgl I + IIE). The order of the fragments in relation to the 5' end and 3' end of the genome was determined either by using fractional-length M-MLV double-stranded DNA for digestion by restriction endonucleases or by redigestion of Sal IA, Sal IB, Hind IIIA, and Hind IIIB fragments with other restriction endonucleases. In addition, a number of other restriction endonucleases that cleave in vitro-synthesized M-MLV double-stranded DNA have also been listed.  相似文献   

7.
2,4-Dimethyl-6-ethoxyquinoline (2), 1,2-dihydro-6-ethoxy-2,2,4-trimethylquinoline nitroxide (3), 2,6-dihydro-2,2,4-trimethyl-6-quinone imine N-oxide (4), 2,6-dihydro-2,2,4-trimethyl-6-quinone imine (5), 1,8′-di(1,2-dihydro-6-ethoxy-2,2,4-trimethylquinoline) (6) and 1,2-dihydro-6-hydroxy-2,2,4-trimethylquinoline (7) have been prepared from 1,2-dihydro-6-ethoxy-2,2,4-trimethylquinoline (1) (ethoxyquin) and their spectroscopic properties (UV, IR, mass and NMR) examined.  相似文献   

8.
Qi J  Chen JJ  Cheng ZH  Zhou JH  Yu BY  Qiu SX 《Phytochemistry》2006,67(13):1372-1377
Iridoid glycosides, harprocumbide A (6'-O-alpha-D-galactopyranosylharpagoside, 1) and harprocumbide B (6'-O-(cis-p-coumaroyl)-procumbide, 2) were isolated from the tubers of Harpagophytum prucumbens D.C., along with nine known iridoid glycosides 6-O-alpha-D-galactopyranosylharpagoside (3), and harpagoside (4), harpagide (5), 8-cinnamoylmyoporoside (6), 8-O-feruloylhapagide (7), procumbide (8), 6'-O-(p-coumaroyl)-procumbide (9), 8-O-(p-coumaroyl)-harpagide (10) and 8-O-(cis-p-coumaroyl)-harpagide (11). Compound 10 showed marginal inhibition activity against macrophages respiratory burst.  相似文献   

9.
Podstawka E  Ozaki Y 《Biopolymers》2008,89(11):941-950
Surface-enhanced Raman scattering (SERS) spectroscopy has been applied to investigate the interaction with a silver colloidal surface of following seven 6-14 fragments of bombesin (BN) C-terminus: cyclo[D-Phe(6),His(7),Leu(14)]BN(6-14), [D-Phe(6),Leu-NHEt(13),des-Met(14)]BN(6-14), [D-Phe(6),Leu(13)-(R)-p-chloro-Phe(14)]BN(6-14), [D-Phe(6),beta-Ala(11),Phe(13),Nle(14)]BN(6-14), [D-Tyr(6),beta-Ala(11),Phe(13),Nle(14)]BN(6-14), [D-Tyr(6),beta-Phe(11),Phe(13),Nle(14)OH]BN(6-14), and [D-Cys(6),Asn(7),D-Ala(11),Cys(14)]BN(6-14), potent r-GRP-R receptor antagonists used in chemotherapy and potential effective drugs in cancer treatment. The adsorption active sites and molecular orientations on the colloidal silver surface have been determined on the basis of SERS "surface selection rules" subsequent to a detailed SERS analysis. In addition, the similarities and differences of these spectra with the SERS spectra of the peptides immobilized on a roughened silver electrode surface have been examined. From the data, suggestion has been made about structural properties of these peptides on the colloidal surface. (c) 2008 Wiley Periodicals, Inc. Biopolymers 89: 941-950, 2008.This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com.  相似文献   

10.
鬼针草中一个新的查耳酮甙   总被引:5,自引:0,他引:5  
从鬼针草BidenspilosaL .地上部分的丙酮提取物中 ,分离鉴定了 1 8个化合物 ,其中包括一个新的查耳酮甙类化合物 (α,3,2′,4′ tetrahydroxy 2′ O β D glucopyranosylchalcone,2 )。其它化合物分别鉴定为butein (1 ) ,okanin 4 methylether 3′ O β glucoside (3) ,sulfuretin (4) ,6 ,7,3′,4′ tetrahydroxyaurone (5) ,海生菊苷 (maritimein ,6) ,(Z ) 6 O (6″ acetyl β D glucopyr anosyl) 6 ,7,3′,4′ tetrahydroxy aurone (7) ,(Z ) 6 O (4″,6″ diacetyl β D glucopyranosyl) 6 ,7,3′,4′ tetrahydroxy aurone (8) ,(Z ) 6 O (3″,4″,6″ triacetyl β D glucopyranosyl) 6 ,7,3′,4′ tetrahydroxy aurone (9) ,木犀草素 (luteolin ,1 0 ) ,槲皮素 (quercetin,1 1 ) ,异槲皮苷 (iso quercitrin,1 2 ) ,芦丁 (rutin,1 3) ,黄芪苷 (astragalin,1 4 ) ,quercetin 3,4′ dimethylether 7 O rutinoside (1 5) ,反式丁烯二酸 (1 6) ,2 β D glucopyranosyloxy 1 hydroxy trideca 3 ,5,7,9,1 1 pentayne (1 7)和 3 β D glucopyranosyloxy 1 hydroxy 6 (E ) tetradecene 8,1 0 ,1 2 triyne (1 8)。  相似文献   

11.
Chemical investigation of the methanol extract of the viscous secretion on the surface of immature fruits of Paulownia tomentosa furnished nine geranylated flavanones, 6-geranyl-5,7-dihydroxy-3',4'-dimethoxyflavanone (1), 6-geranyl-3',5,7-trihydroxy-4'-methoxyflavanone (2), 6-geranyl-4',5,7-trihydroxy-3',5'-dimethoxyflavanone (3), 6-geranyl-4',5,5',7-tetrahydroxy-3'-methoxyflavanone (4), 6-geranyl-3,3',5,7-tetrahydroxy-4'-methoxyflavanone (5), 4',5,5',7-tetrahydroxy-6-[6-hydroxy-3,7-dimethyl-2(E),7-octadienyl]-3'-methoxyflavanone (6), 3,3',4',5,7-pentahydroxy-6-[6-hydroxy-3,7-dimethyl-2(E),7-octadienyl]flavanone (7), 3,3',4',5,7-pentahydroxy-6-[7-hydroxy-3,7-dimethyl-2(E)-octenyl]flavanone (8), and 3,4',5,5',7-pentahydroxy-3'-methoxy-6-(3-methyl-2-butenyl)flavanone (9), along with six known geranylated flavanones. Among these, compounds 4, 6-9 and the known 6-geranyl-3',4',5,7-tetraahydroxyflavanone (diplacone), 6-geranyl-3,3',4',5,7-pentahydroxyflavanone (diplacol) and 3',4',5,7-pentahydroxy-6-[7-hydroxy-3,7-dimethyl-2(E)-octenyl]flavanone showed potent radical scavenging effects towards DPPH radicals.  相似文献   

12.
Nine analogues of methyl acarviosin (1), the core structure of acarbose and its homologues, the 6-hydroxy-(2), 6-azido-(3), 6-amino- (4), 6-acetamido-(5), 6-methoxy-(6), 6-hydroxy-2-O-methyl-(8), and 6-hydroxy-3-O-methyl derivatives (9), including the 5-methoxycarbonyl analogue (7) and 3,6-anhydro derivative (10) of 2, were synthesized by chemical modification of the sugar part of 2 derived by condensation of methyl 3,4-anhydro-alpha-D-galactopyranoside (17) and 4,7:5,6-di-O-isopropylidenevalienamine (26) or by direct coupling between 26 and the 6-substituted methyl 3,4-anhydro-alpha-D-galactopyranoside derivatives. Compounds 2 and 8 show notable inhibitory activity against yeast alpha-D-glucosidase almost comparable to that of 1. Introduction of a polar substituent at C-6 of 1 decreases the inhibitory activity. Interestingly, inversion of the conformation of the sugar part of 1 by introduction of the 3,6-anhydro bridge elicits almost no effect on the inhibitory activity.  相似文献   

13.
In order to elucidate the structure-activity relationship of griseofulvin (1), (±)-6′-demethyl analog (3), 2′-demethoxy-6′-demethyldihydro analog (4), (±)-dechloro-6′-ethyl analog (5), (±)-dechloro-6′-epi-ethyl analog (6), (±)-6′-ethyl analog (7) and (±)-6′-epi-ethyl analog (8) were synthesized by a Diels-Alder cycloaddition of alkylidene ketones (16, 17, 18, 19 and 20) with modified 1,3-butadienes (21 or 22). Their biological activities were examined against fungi.  相似文献   

14.
Li A  Kong F 《Carbohydrate research》2004,339(11):1847-1856
Two arabinogalactosyl nonasaccharides, beta-D-Galp-(1-->6)-[alpha-L-Araf-(1-->3)]-beta-D-Galp-(1-->6)-beta-D-Galp-(1-->6)-beta-D-Galp-(1-->6)-[alpha-L-Araf-(1-->5)-alpha-L-Araf-(1-->3)]-beta-D-Galp-(1-->6)-beta-D-Galp and beta-D-Galp-(1-->6)-[alpha-L-Araf-(1-->5)-alpha-L-Araf-(1-->3)]-beta-D-Galp-(1-->6)-beta-D-Galp-(1-->6)-beta-D-Galp-(1-->6)-[alpha-L-Araf-(1-->3)]-beta-D-Galp-(1-->6)-beta-D-Galp, were synthesized as their 4-methoxyphenyl glycosides with 2,3,4,6-tetra-O-benzoyl-alpha-D-galactopyranosyl trichloroacetimidate (1), 6-O-acetyl-2,3,4-tri-O-benzoyl-alpha-D-galactopyranosyl trichloroacetimidate (14), 4-methoxyphenyl 3-O-allyl-2,4-di-O-benzoyl-beta-D-galactopyranoside (2), 4-methoxyphenyl 2,3,4-tri-O-benzoyl-beta-D-galactopyranoside (5), 2,3,5-tri-O-benzoyl-alpha-L-arabinofuranosyl trichloroacetimidate (8), and 2,3,5-tri-O-benzoyl-alpha-L-arabinofuranosyl-(1-->5)-2,3-di-O-benzoyl-alpha-L-arabinofuranosyl trichloroacetimidate (11), as the key synthons. The tetra- (10) and pentasaccharide donor (13), and the tetra- (20) and pentasaccharide acceptor (22) were synthesized based on these synthons through simple transformations. Coupling of 22 with 10, and coupling of 20 with 13 and subsequent deacylation gave nonasaccharides 24 and 26, respectively, consisting of beta-(1-->6)-linked glactopyranosyl backbone and alpha-(1-->3)-linked arabinofuranosyl side chains of different size.  相似文献   

15.
The lipid extract of the temperate red alga Rhodymenia pertusa has yielded four eicosanoid metabolites, three of which are new natural products. Using principally NMR and MS techniques, their structures were deduced as 5R,6S-dihydroxy-7(E),9(E),11(Z),14(Z)-eicosatetraenoic acid (5R,6S-diHETE), 5R*,6S*-dihydroxy-7(E),9(E),11(Z),14(Z),17(Z)-eicosapentaenoic acid (5R*,6S*-diHEPE), 5-hydroxy-6(E),8(Z),11(Z),14(Z)-eicosatetraenoic acid (5-HETE), 5-hydroxy-6(E),8(Z),11(Z),14(Z),17(Z)-eicosapentaenoic acid (5-HEPE). The co-occurrence of these metabolites strongly suggests that R. pertusa contains a unique 5R-lipoxygenase system acting on both arachidonic and eicosapentaenoic acids.  相似文献   

16.
为分析菊科橐吾属植物离舌橐吾Ligularia veitchiana(Hemsl.)Greenm中艾里莫酚烷型倍半萜类的化学成分,并对其进行抗肿瘤活性研究,实验综合运用硅胶柱色谱、反相硅胶柱色谱以及制备型高效液相等色谱方法,从其根茎的95%乙醇提取物的乙酸乙酯部位中分离得到了13个艾里莫酚烷型倍半萜类化合物,根据化合物的理化性质及其波谱学数据鉴定为:eremophilenolide(1),eremophila-7(11),9-dien-8-one(2),eremophil-6-en-11-ol(3),8-oxo-eremophil-6-en-11-one(4),(6α,8α)-6-hydroxyeremophil-7(11)-en-12,8-olide(5),8β-hydroxyeremophil-7(11)-en-12,8α-olide(6),6β-hydroxy-8α-methoxyeremophil-7(11)-12,8β-olide(7),2α-hydroxyeremophil-11-en-9-one(8),6β-methoxy-8β-hydroxyeremophil-7(11)-en-12,8α-olide(9),6β-hydroxyeremophil-7(11)-en-12,8β-olide(10),6β-hydroxy-8β-methoxyeremophil-7(11)-12,8α-olide(11), 6β,8β-dihydroxyeremophil-7(11)-en-12,8α-olide(12)和6β,8α-dihydroxyeremophil-7(11)-en-12,8β-olide(13)。其中,化合物5和10、7和11~13为三对非对映异构体。除化合物3和5外,所有化合物均为首次从该植物中分离得到。运用MTT法对所有化合物进行体外抗肿瘤细胞活性的筛选,结果表明其对胃癌细胞HGC-27和宫颈癌细胞Caski均未显示细胞毒作用。  相似文献   

17.
A methanol extract of marjoram leaves strongly inhibited rat intestinal alpha-glucosidase. Five 6-hydroxyflavonoids, 6-hydroxyapigenin (scutellarein; IC50 for sucrose hydrolysis by rat intestinal alpha-glucosidase, 12 microM), 6-hydroxyapigenin-7-O-beta-D-glucopyranoside (> 500 microM), 6-hydroxyluteolin-7-O-beta-D-glucopyranoside (300 microM), 6-hydroxyapigenin-7-O-(6-O-feruloyl)-beta-D-glucopyranoside (>500 microM), and 6-hydroxyluteolin-7-O-(6-O-feruloyl)-beta-D-glucopyranoside (> 500 microM), were isolated as active principles and related compounds. The two feruloylglucosides are novel compounds.  相似文献   

18.
It has been confirmed by methylation analyses and chemical syntheses that three isomers of branched cyclomaltoheptaose (beta CD) isolated from the mother liquors of a large-scale preparation of beta CD with Bacillus ohbensis cyclomaltodextrin glucanotransferase are 6(1),6(4)-di-O-(alpha-D-glucopyranosyl)-cyclomaltoheptaose (1), 6(1),6(3)-di-O-(alpha-D-glucopyranosyl)-cyclomaltoheptaose (2), and 6-O-(alpha-isomaltosyl)-cyclomaltoheptaose (4) instead of 6(1),6(2)-di-O-(alpha-D-glucopyranosyl)-cyclomaltoheptaose (3), which was erroneously characterized in an earlier paper. Compound 3 has been newly isolated from a glucosyl-beta CD mixture prepared by hydrolysis with glucoamylase of a maltosyl-beta CD mixture, synthesized from maltose and beta CD through the reverse action of pullulanase. Chromatographic behavior and spectral data (13C-n.m.r. and f.a.b.-m.s.) of these isomers of branched beta CD (1-4), as well as those of another isomer prepared by the reverse action of hydrolytic enzymes, 6-O-(alpha-maltosyl)-cyclomaltoheptaose (5), were compared.  相似文献   

19.
Acylated iridoid glucosides from Veronica anagallis-aquatica   总被引:1,自引:0,他引:1  
Three new (1-3) and four known iridoid glucosides (4-7) as well as a known phenylethanoid glycoside (8) were isolated from the aerial parts of Veronica anagallis-aquatica and their structures were determined as 6'-O-benzoyl-8-epiloganic acid named aquaticoside A (1), 6'-O-p-hydroxybenzoyl-8-epiloganic acid named aquaticoside B (2), 6'-O-benzoyl-gardoside named aquaticoside C (3), veronicoside (4), catalposide (5), verproside (6), verminoside (7) and martynoside (8) on the basis of 1D and 2D NMR spectral analysis.  相似文献   

20.
Three covalently closed circular species of extrachromosomal deoxyribonucleic acid have been identified by electron microscopic analysis in strains of Rhodopseudomonas spheroides. The weights of these plasmids, as determined from contour length, are about 75 X 10(6), 66 X 10(6), and 28 X 10(6) daltons for both aerobically grown and photosynthetically grown R. spheroides strain 2.4.1 (NRS) and for the photosynthetically incompetent strain V-2 (obtained by N-methyl-N-nitro-N'nitrosoguanidine mutagenesis) and 74 X 10(6), 66 X 10(6) and 34 X 10(6) daltons for a second photosynthetically incompetent strain, SLS I (obtained by incubating strain 2.4.1 [NRS] in medium containing sodium lauryl sulfate). Buoyant densities uere found to be 1.717 g/cm3 (58% guanine plus cytosine) for the plasmids of 66 X 10(6), 28 X 10(6), and 34 X 10(6) daltons in weight and 1.724 g/cm3 (65% guanine plus cytosine) for those weighing about 75 X 10(6) daltons. Possible functions of these plasmids are discussed.  相似文献   

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