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1.
Two new iridoid glycosides, karsoside [1] and scropolioside D [2], were isolated from the aerial parts of Scrophularia ilwensis. Their structures were elucidated on the basis of chemical and spectral data as 6'-O-(beta-D-xylopyranosyl)-methylcatalpol and 6-O-[(2",4"-di-O-acetyl-3"-O-trans-cinnamoyl)-alpha-L-rhamnopyranosyl]- catalpol, respectively. Additionally, four known iridoids (aucubin, harpagide, 8-O-acetylharpagide, and ajugol), a phenylpropanoid glycoside (angoroside C), and two flavonoids (quercetin-3-O-rutinoside and kaempferol-3-O-rutinoside) were isolated and identified.  相似文献   

2.
During the reisolation of the trimeric naphthoquinone derivative conocurvone [1] from an extract of the Australian shrub Conospermum incurvum, six monomeric naphthoquinones were isolated. These include three novel 1,4-naphthoquinone derivatives: 3-methyl-14,15-dihydro-15-hydroxyteretifolione B [3], 3-methyl-14,15-dihydro-15-hydroxyteretifolione B methyl ether [4], and 2,3-dimethyl-6-hydroxy-7-methoxy-1,4-naphthoquinone [5]. In addition, the previously reported compounds 3-methylteretifolione B [6], 3-methylteretifolione B methyl ether [7], and 8-geranyl-2,7-dihydroxy-3-methyl-1,4-naphthoquinone [8] were isolated and identified. The structures of the novel 1,4-naphthoquinones were elucidated by spectral methods. While conocurvone [1] is a potent inhibitor of HIV-1-induced cell killing, all of the monomeric naphthoquinone derivatives were inactive against HIV-1.  相似文献   

3.
Three new triterpenoid saponins were isolated from the roots of Gypsophila oldhamiana. Their structures were elucidated, using a combination of homonuclear and heteronuclear 2D nmr and fabms, as 3-0-beta-D-galactopyranosyl-(1-->2)-[beta-D-xylopyranolyl-(1-->3)] -beta-D-glucuronopyranosyl quillaic acid methyl ester [1], 3-0-beta-D-galactopyranosyl-(1-->2)-[beta-D-xylopyranosyl-(1-->3)]-beta- D-glucuronopyranosyl gypsogenin methyl ester [2], and 3-0-beta-D-galactopyranolsyl-(1-->2)-[beta-D-xylopyranosyl-(1-->3) ]-beta-D-glucuronopyranosyl quillaic acid 28-[0-beta-D-fucopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->3)]-alpha-L- rhamnopyranosyl] ester.  相似文献   

4.
Using cytotoxicity as a guide to fractionation, one novel acetogenin, annoreticuin-9-one [3], and four known cytotoxic acetogenins, squamone [4], solamin [5], annomonicin [6] and rolliniastatin 2 [7], were isolated from active extracts of the leaves of the Formosan plant Annona reticulata. Their structures were elucidated on the basis of uv, ir, 1H- and 13C-nmr, and ms data of the natural compounds and their derivatives.  相似文献   

5.
Two complete and two partial structure-activity relationship scans of the active fragment of human growth hormone-releasing hormone, [Nle27]-hGHRH(1-29)-NH2, have identified potent agonists in vitro. Single-point replacement of each amino acid by alanine led to the identification of [Ala8]-, [Ala9]-, [Ala15]- (Felix et al. Peptides 1986 1986, 481), [Ala22]-, and [Ala28, Nle27]-hGHRH(1-29)-NH2 as being 2-6 times more potent than hGHRH(1-40)-OH (standard) in vitro. Nearly complete loss of potency was seen for [Ala1], [Ala3], [Ala5], [Ala6], [Ala10], [Ala11], [Ala13], [Ala14], and [Ala23], whereas [Ala16], [Ala18], [Ala24], [Ala25], [Ala26], and [Ala29] yielded equipotent analogues and [Ala7], [Ala12], [Ala17], [Ala20], [Ala21], and [Ala27] gave weak agonists with potencies 15-40% that of the standard. The multiple-alanine-substituted peptides [MeTyr1,Ala15,22,Nle27]-hGHRH(1-29)-NH2 (29) and [MeTyr1,Ala8,9,15,22,28,Nle 27]-hGHRH(1-29)-NH2 (30) released growth hormone 26 and 11 times, respectively, more effectively than the standard in vitro. Individual substitution of the nine most potent peptides identified from the Ala series with the helix promoter alpha-aminoisobutyric acid (Aib) produced similar results, except for [Aib8] (doubling vs [Ala8]), [Aib9] (having vs [Ala9]), and [Aib15] (10-fold decrease vs [Ala15]). A series of cyclic analogues was synthesized having the general formula cyclo(25-29)[MeTyr1,-Ala15,Xaa25,Nle27,Yaa29+ ++]-GHRH(1-29)-NH2, where Xaa and Yaa represent the bridgehead residues of a side-chain cystine or [i-(i + 4)] lactam ring. The ring size, bridgehead amino acid chirality, and side-chain amide bond location were varied in this partial series in an attempt to maximize potency. Application of lactam constraints in the C-terminus of GHRH(1-29)-NH2 identified cyclo(25-29)[MeTyr1,Ala15,DAsp25,Nle27,Orn29+ ++]-hGHRH(1-29)-NH2 (46) as containing the optimum bridging element (19-membered ring) in this region of the molecule. This analogue (46) was 17 times more potent than the standard. Equally effective was an [i-(i + 3)] constraint yielding the 18-membered ring cyclo(25-28)[MeTyr1,Ala15,Glu25,Nle,27Lys28]- hGHRH-(1-29)-NH2 (51) which was 14 times more potent than the standard. A complete [i-(i + 3)] scan of cyclo(i,i + 3)[MeTyr1,Ala15,Glui,Lys(i + 3),Nle27]-hGHRH(1-29)-NH2 was then produced in order to test the effects of a Glu-to-Lys lactam bridge at all points in the peptide. Of the 26 analogues in the series, 11 had diminished potencies of less than 10% that of the agonist standard, 4 were weak agonists (15-40% relative potency), and 4 analogues were equipotent to the standard. The 7 most potent analogues ranged in potency from 3 to 14 times greater than that of the standard and contained the [i-(i + 3)] cycles between residues 4-7, 5-8, 9-12, 16-19, 21-24, 22-25, and 25-28. The combined results from these systematic studies allowed for an analysis of structural features in the native peptide that are important for receptor activation. Reinforcement of the characteristics of amphiphilicity, helicity, and peptide dipolar effects, using recognized medicinal chemistry approaches including introduction of conformational constraints, has resulted in several potent GHRH analogues.  相似文献   

6.
Following the characterization of anchinopeptolide A[1], three new congeneric dimeric peptide alkaloids, named anchinopeptolides B [2], C[3], and D[4], have been isolated from the Mediterranean sponge Anchinoe tenacior. A fourth compound, cycloanchinopeptolide C[5], which is related to anchinopeptolide C[3] by a head-to-head intramolecular [2+2] cyclo-addition reaction, has also been isolated. The structures of these peptide alkaloids have been elucidated on the basis of spectral evidence. Anchinopeptolides bind to the somatostatin, human B2 bradykinin, and neuropeptide Y receptors.  相似文献   

7.
Three new bicoumarin metabolites, isokotanins A [1], B [2], and C [3], were isolated from the sclerotia of Aspergillus alliaceus. Isokotanin A is a regioisomer of the known bicoumarin kotanin [4]. The structures and spectral assignments for 1-3 were determined on the basis of selective INEPT, HMQC, and NOESY nmr data, as well as by chemical interconversions. Isokotanins B and C show activity against the corn earworm Helicoverpa zea and the dried fruit bettle Carpophilus hemipterus. The known compounds kotanin [4], desmethylkotanin [5], nominine, and paspaline were also isolated from extracts of A. alliaceus sclerotia.  相似文献   

8.
The structure of pyramidatine [1], a new bisamide alkaloid from leaves of Aglaia pyramidata, was determined through extensive nmr studies, including homonuclear COSY, NOESY, APT, HETCOR, and selective INEPT techniques. Revision of the 13C-nmr assignment of piriferine [2], an alkaloid previously isolated from A. pirifera, was achieved by examination of several 2D nmr spectra (homonuclear COSY, NOESY, and HETCOR) and confirmed by selective INEPT nmr experiments. Evaluation of the cytotoxic potential of the two alkaloids, along with two other bisamides from Aglaia odorata, odorine [3] and 5'-epi-odorine [4], was carried out in eleven human cancer cell lines. None of these bisamides showed significant cytotoxicity. Nevertheless, piriferine [2], odorine [3], and 5'-epi-odorine [4] were found to inhibit the growth of the vinblastine-resistant KB cells by enhancing the anticancer activity of vinblastine.  相似文献   

9.
The constituents in the fruit of Anthriscus sylvestris Hoffm. were investigated, and four lignans [deoxypodophyllotoxin, morelensin, (-)-deoxypodorhizone, and (-)-hinokinin], one phenylpropanoid [1-(3',4'-dimethoxyphenyl)-1 xi-hydroxy-2-propene], two phenylpropanoid esters [3',4'-dimethoxycinnamyl (Z)-2-angeloyloxymethyl-2-butenoate and 3',4'-dimethoxycinnamyl (Z)-2-tigloyloxymethyl-2-butenoate], and one polyacetylenic compound (falcarindiol) were isolated. Their antiproliferative activity against MK-1, HeLa and B16F10 cell lines is reported.  相似文献   

10.
A new triterpenoid saponin, designated macrophyllicinin [1], has been isolated from the MeOH extract of the whole plant of Primula macrophylla. Its structure was established by chemical and spectroscopic means as 3 beta-O-[alpha-L-rhamnopyranosyl-(-->2)-beta-D-glucopyranosyl-(-->2)- beta-D-galactopyranosyl-(-->2)-beta-D-glucuronopyranosyl]-6 beta,16 alpha-dihydroxyolean-12-en-28-acetate. The aglycone 2 of this saponin is also a new compound.  相似文献   

11.
myo-Inositol-1-phosphate synthase (EC 5.5.1.4) from rat testis, Acer pseudoplatanus L. cell culture and Oryza sativa L. cell culture, converted D-[5-3H]glucose 6-phosphate to myo-[2-3H]inositol 1-phosphate at rates ranging from 0.21 to 0.48 that of unlabeled substrate. D-[3-3H]- and D-[4-3H]glucose 6-phosphate were converted at approximately the same rate as that of unlabeled substrate. In the case of testis enzyme, storage as a frozen solution further lowered the rate with D-[5-3H]glucose 6-phosphate as substrate. When the reaction was run in [3H]water, no 3H appeared in myo-inositol 1-phosphate but a small amount was recovered in substrate isolated from the final reaction mixture. These data support the involvement of carbon 5 of D-glucose 6-phosphate in the mechanism proposed for this conversion.  相似文献   

12.
Seven antioxidative serotonin derivatives were isolated from safflower (Carthamus tinctorius L.) oil cake. Their structures were established as N-[2-(5-hydroxy-1H-indol-3-yl)ethyl]ferulamide (1), N-[2-(5-hydroxy-1H-indol-3-yl)ethyl]-p-coumaramide (2), N,N'-[2,2'-(5,5'-dihydroxy-4,4'-bi-1H-indol-3,3'-yl)diethyl]- di-p-coumaramide (3), N-[2-[3'-[2-(p-coumaramido)ethyl]-5,5'-dihydroxy- 4,4'-bi-1H-indol-3-yl]ethyl]ferulamide (4), and N,N'-[2,2'-(5,5'-dihydroxy-4,4'-bi-1H-indol-3,3'-yl)diethyl]- diferulamide (5), N-[2-[5-(beta-D-glucosyloxy)-1H-indol-3-yl)ethyl]- p-coumaramide (6), and N-[2-[5-(beta-D-glucosyloxy)-1H-indol-3-yl)ethyl]ferulamide (7). Antioxidative activities of the compounds were measured by the ferric thiocyanate method and the alpha,alpha-diphenyl-beta-picrylhydrazyl (DPPH) method, and compounds 1-5 were found to have relatively strong antioxidative activity.  相似文献   

13.
Five oligosaccharide alpha1-phosphates and one sulfated glycopeptide have been isolated from the hemofiltrate of one patient with end-stage renal disease. Isolation of these compounds has been achieved using reverse osmosis, ion-exchange and size-exclusion chromatography and high performance liquid chromatography. The structures were predominantly elucidated by one- and two-dimensional 1H and 31P NMR spectroscopy. The chemical structures were determined to be: 1 NeuAc alpha2-3Gal alpha1-OPO3H2; 2 NeuAc alpha2-6Galbeta1-4GlcNAc alpha1-OPO3H2; 3 NeuAc alpha2-3Galbeta1-3GalNAc alpha1-OPO3H2; 4 NeuAc alpha2-3Galbeta1-3[NeuAc alpha2-6]GalNAc alpha1-OPO3H2 (proposed structure); 5 Fuc alpha1-2Galbeta1-4[Fuc alpha1-3]GlcNAc alpha1-OPO3H2; 6 HOSO3-4Fuc alpha1-6GlcNAcbeta1-NAsn. While 2 and 3 have been previously characterized as compounds of urine and hemofiltrate, the oligosaccharide alpha1-phosphates 1, 4, and 5 could be isolated--to our knowledge--for the first time from biological material. Compound 6 is the first glycopeptide reported to contain a 4-sulfated fucose residue.  相似文献   

14.
Four new allose-containing triterpenoid saponosides, scabriosides A, B, C and D were isolated from the roots of Scabiosa rotata. Their structures were established as 3-O-beta-D-xylopyranosyl-28-O-[beta-D-allopyranosyl (1-->6)-beta-D-glucopyranosyl]-pomolic acid, 3-O-[alpha-L-rhamnopyranosyl (1-->2)-beta-D-xylopyranosyl]-28-O-[beta-D-allopyranosyl (1-->6)-beta-D-glucopyranosyl]-pomolic acid, 3-O-[alpha-L-rhamnopyranosyl (1-->2)-alpha-L-arabinopyranosyl]-28-O-[beta-D-allopyranosyl (1-->6)-beta-D-glucopyranosyl]-pomolic acid, and 3-O-[beta-D-glucopyranosyl (1-->3)-alpha-L-rhamnopyranosyl (1-->2)-beta-D-xylopyranosyl]-28-O-[beta-D-allopyranosyl(1-->6) -beta-D-glucopyranosyl]-pomolic acid, respectively, by the help of spectral evidence (IR, 1D- and 2D-NMR, FAB-MS).  相似文献   

15.
Twelve rats were trained to press one lever after cocaine injection (3 mg/kg i.p.) and another lever after saline injection. Once rats were reliably discriminating cocaine from saline, other drugs were examined for their efficacies in substituting for cocaine. The dopamine uptake inhibitors WIN 35,428 [2-beta-carbomethoxy-3-beta-(4-fluorophenyl)tropane-1,5-naphthalene - disulfonate] and GBR 12909 (1-[2-bis(4-fluorophenyl)methoxy]ethyl]-4-[3- phenylpropyl]piperazine dihydrochloride) fully substituted for cocaine (cocaine responding > 80%), whereas the peripherally active cocaine methiodide and the 5-hydroxytryptamine uptake inhibitor fluoxetine did not substitute at all. Pentobarbital also failed to produce any cocaine-appropriate responding. Two selective norepinephrine uptake inhibitors were tested: tomoxetine fully substituted for the 3-mg/kg dose of cocaine and nisoxetine approached full substitution (79.7% cocaine responding). The direct-acting dopamine D-1 agonists SKF 38393 [(+-)-7-bromo-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-be nzazepin e HCl], SKF 77434 [(+-)-7,8-dihydroxy-3-allyl-1-phenyl-2,3,4,5-tetrahydro-1H-benzazepine HCl] and SKF 75670 [3-methyl-7,8-dihydroxyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benza zep ine HBr] fully substituted for cocaine, whereas the peripherally active dopamine D-1 agonist fenoldopam did not. Of four dopamine D-2 agonists tested, only quinpirole fully substituted; the others (N-0434 [(+-)-2-(N-propyl-N-phenylethylamino)-5-hydroxytetralin], (-)-NPA [R(-)-propylnorapomorphine HCl] and SDZ 208-912 (N-[(8-)-2,6-dimethylergoline-8-yl]-2,2-dimethyl-propanamide)) produced very limited partial substitution (cocaine responding < 32%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

16.
A new antiherpetic agent, AH-1763 IIa, was isolated from the culture broth of strain No. 1763 identified as Streptomyces cyaneus. It was purified through column chromatographies of Diaion HP-10 and silica gel. The structure was determined to be 11-hydroxy-5-methyl-2-(2-hydroxy-1-methylpropyl)-4H-anthraceno [1,2-b]pyran-4,7,12-trione by several spectroscopic experiments, that is a new antibiotic belonging to pluramycin-group.  相似文献   

17.
Mechanisms of primary fluid formation by macropodine mandibular glands were investigated in anaesthetized red kangaroos using ion-transport and carbonic anhydrase inhibitors. Bumetanide at carotid plasma concentrations of 0.005-0.1 mmol/l progressively reduced a stable, acetylcholine-evoked flow rate of 1.02 +/- 0.024 ml/min to 0.16 +/- 0.016 ml/min (mean +/- SEM). Concurrently, saliva [Na], [Cl] and osmolality decreased, [K] and [HCO3] increased and HCO3 excretion was unaffected. High-rate cholinergic stimulation was unable to increase salivary flow above 12 +/- 1.5% of that for equivalent pre-bumetanide stimulation. Furosemide (1.0 mmol/l) and ethacrynate (0.5 mmol/l) caused depression of salivary flow and qualitatively similar effects on ion concentrations to those of bumetanide. Amiloride (up to 0.5 mmol/l) caused no reduction in salivary flow rates or [Na] but decreased [K] and [Cl] and increased [HCO3]. When compared with bumetanide alone, amiloride combined with bumetanide further augmented [K] and [HCO3] and lowered [Cl], but had no additional effects on Na or flow. At the higher level, 4-acetamido-4'- isothiocyanatostilbene-2,2'disulphonic acid (SITS) (0.05 and 0.5 mmol/l) stimulated fluid output, increased [HCO3] and [protein], and depressed [Na], [K] and [Cl]. Relative to bumetanide alone, SITS given with bumetanide had no additional effects on salivary flow or electrolytes. Methazolamide (0.5 mmol/l) in combination with bumetanide curtailed the decrease in [Cl] and the increases in [K] and [HCO3] associated with bumetanide. The residual methazolamide-resistant HCO3 excretion was sufficient to support 2-6% of primary fluid secretion. It was concluded that secretion of primary fluid by the kangaroo mandibular gland is initiated mainly (> 90%) by Cl transport resulting from Na-K-2Cl symport activity. A small proportion of the fluid secretion (up to 6%) appears to be supported by HCO3 secretion. No evidence was found for fluid secretion being dependent on Cl transport involving Na/H and Cl/HCO3 antiports or on HCO3 synthesis involving carbonic anhydrase.  相似文献   

18.
Two novel triterpenoidal saponins, called calliandra saponins A and E, were isolated from the branches of Calliandra anomala (Kunth) Macbr. On the basis of the chemical and physiocochemical evidence, their structures were defined as 3-O-alpha-L-arabinopyranosyl-(1-->2)-alpha-L-arabinopyranosyl++ +-(1-->6)-2- acetamido-2-deoxy-beta-D-glucopyranosyl echinocystic acid 28-O-(beta-D-glucopyranosyl-(1-->3)-[beta-D-xylopyranosyl-(1-->3)-beta-D - xylopyranosyl-(1-->4)]-alpha-L-rhamnopyranosyl-(1-->2)-[(6S)-2-trans- 2,6-dimethyl-6-O-beta-D-xylopyranosyl-2,7-octadienoyl-(1-->6)]-bet a-D- glucopyranosyl) ester (4) and 3-O-alpha-L-arabinopyranosyl-(1-->2)-alpha-L-arabinopyranosyl++ +-(1-->6)-2- acetamido-2-deoxy-beta-D-glucopyranosyl echinocystic acid 28-O-[beta-D-glucopyranosyl-(1-->3)-[beta-D-xylopyranosyl-(1-->3)-beta-D - xylopyranosyl-(1-->4)]-alpha-L-rhamnopyranosyl-(1-->2)-[(6'S)-2'-trans- 2',6'-dimethyl-6'-O-(2-O-(6S)-2-trans-2,6-dimethyl-6-hydroxy-2,7-octa dienoyl)- beta-D-xylopyranosyl-2',7'-octadienoyl-(1-->6)]-beta-D-glucopyr ano syl] ester (5), respectively.  相似文献   

19.
Syntheses of 4-chloro-2-mercapto-5-methyl-N-(5-R1-6-R2-benzimidazol-2-yl) benzenesulphonamides [II-V], their disulfides [IIa-IVa] and S,N-substituted derivatives [VI-IX] were described. The probable mechanism for the reactions was suggested. The moderate anticancer activity was observed in vitro for compounds [II-IV].  相似文献   

20.
1. To examine the metabolic fate of (1RS, trans)- or (1RS, cis)-tetramethrin [3, 4, 5, 6-tetrahydrophthalimidomethyl (1RS, trans)- or (1RS, cis)-chrysanthemate], rat was administered a single oral dose of trans- or cis-[alcohol-14C]tetramethrin at dose levels of 2 or 250 mg/kg. 2. The radiocarbon was almost completely eliminated from rat within 7 days after administration in all groups. 14C-recoveries (expressed as percentages relative to the dosed 14C) in faeces and urine were 38-58 and 42-58% respectively in rat administrated trans-[alcohol-14C]tetramethrin, and in faeces and urine were 66-91 and 9-31% respectively in rat administered cis-[alcohol-14C]tetramethrin. 3. Fourteen metabolites found in excreta were purified by using several chromatographic techniques and identified by spectroanalyses (nmr and MS). Five sulphonate derivatives and three dicarboxylic acid derivatives were found. 4. The main metabolites were sulphonate derivatives in the faeces, and in the urine, alcohols, dicarboxylic acid and reduced metabolites derived from the 3,4,5,6-tetrahydrophthalimide moiety.  相似文献   

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