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1.
Chemical constituents of Taraxacum formosanum   总被引:1,自引:0,他引:1  
Three new compounds, taraxacine-A (1), taraxacine-B (2) and taraxafolin (3) together with twenty-five known compounds, which include two beta-carboline alkaloids, two indole alkaloids, two chlorophylls, two flavonoids, one coumarin, two triterpenoids, one monoterpenoid, one ionone, four steroids and eight benzenoids, were isolated and characterized from the fresh aerial parts of Taraxacum formosanum. Structures of new compounds were determined by spectral analysis.  相似文献   

2.
Continuous investigation of the CHCl3‐soluble and n‐hexane fractions of the leaves of Litsea acutivena Hayata (Lauraceae) led to the isolation of one new butanolide, acutilactone ( 1 ), one new lactone, 4‐nonacosyl‐dihydrofuran‐2‐one ( 2 ), together with 15 known compounds. The known compounds included one butanolide, one norisoprenoid, one quinone, two steroids, one triterpenoid, one coumarin, two fatty acids, one amide, and five other compounds. The structures of these compounds were determined by means of spectral analyses.  相似文献   

3.
Two new iridoid glycosides designated as senburiside III (2) and senburiside IV (3), together with one known iridoid glycoside senburiside I (1) and three known secoiridoid glucosides swertiamarin (4), gentiopicroside (5) and sweroside (6), were isolated from the whole plant of Swertia franchetiana. The structures of the two new compounds were elucidated by spectroscopic methods.  相似文献   

4.
A new and efficient synthetic pathway employed the aldol condensation between the acetophenone (3) and vanillin derivative (4) resulted in the precursor chalcone intermediate (14). The target compound viscolin (1) could be afforded through the hydrogenation of the chalcone and followed by deprotection. The present strategy described the development of a more efficient procedure that allowed large-scale production of viscolin for the further research of biological activity both in vitro and in vivo.  相似文献   

5.
Secostrychnosin ( 1 ), a new secoiridoid, as well as seven compounds never before isolated from nature: 4‐tert‐butyl‐2‐oxazolidinone ( 2 ), 3‐acetoxyindole ( 3 ), indole‐2‐carboxylic acid ( 4 ), benzocaine ( 5 ), 3‐acetylindole ( 6 ), butylparaben ( 7 ) and 2‐hydroxy‐3‐methoxybenzaldehyde ( 8 ), together with fifty other known compounds, have been isolated from the stem of Strychnos cathayensis. These compounds include twenty‐three alkaloids, twelve benzenoids, four steroids, three flavonoids, three iridoids, two triterpenoids, two secoiridoids, two fatty acids, one lignan, one acetophenone, one coumarin, one chromane, one tetraterpenoid, one tannin, and one organic acid. The structures of these compounds were determined by means of spectralanalyses.  相似文献   

6.
Two new diterpenoids, loxocalyxin A ( 1 ) and 13‐epiloxocalyxin A ( 2 ), and two new sesquiterpenoids, loxocalyxins B and C ( 3 and 4 , resp.), together with three known compounds, were isolated from the MeOH extract of the whole plant of Loxocalyx urticifolius Hemsl . The structures of the new compounds were established by means of spectroscopic analysis including one‐ and two‐dimensional NMR spectroscopy. All new structures were confirmed by X‐ray crystallographic analysis. Their absolute configurations were established.  相似文献   

7.
Two new terpenoids from fruits of Ziziphus jujuba   总被引:1,自引:0,他引:1  
One new ceanothane-type triterpene and one new sesquiterpene,together with two known triterpenes were isolated from the fruits of Ziziphus jujuba Mill.(Rhamnaceae).Based on the spectral analyses,the structures of two new compounds were elucidated as 2α-aldehydo-A(1)-norlup-20(29)-en-27,28-dioic acid(zizyberanal acid)(1),and zizyberanone(2).While the two known triterpenes were identified as zizyberanalic acid(3)and ursofic acid(4).  相似文献   

8.
From the chloroform extract of the aerial parts of Salvia xanthocheila, one new triterpene, together with two known diterpenes, two known flavonoids and a phytosterol was isolated. On the basis of comprehensive spectroscopic analyses, including electron ionisation mass spectra, 1H-NMR, 13C-NMR, 1-D nuclear Overhauser effect, distortionless enchancement by polarisation transfer, H,H correlation spectroscopy, heteronuclear multiple quantum coherence, rotating frame Overhauser enhancement spectroscopy spectra and comparison with spectral data of known compounds, the structure of new compounds was established as 1β,3β-dihydroxy-olean-9(11),12-dienyl (1). The five known compounds (2-6) were 7α-acetoxyroyleanone, taxodione, salvigenin, apigenin-7,4'-dimethyl ether and β-sitosterol, respectively. These known structures are isolated from the aerial parts of S. xanthocheila for the first time.  相似文献   

9.
A new phenolic ester 2-( p-hydroxyphenyl)ethyl eicosaheptanoic acid ester (1) and a known one hexacosylferulate (2) were isolated from the acetone extract of Salvia microphylla. In addition, two sesquiterpenes beta-eudesmol (3) and 8alpha-hydroxy-beta-eudesmol (4), a diterpene carnosic acid 12-methyl ether (12-methoxycarnosic acid) (5), three triterpenes erithrodiol 3-acetate, oleanolic acid, lupeol and beta-sitosterol were obtained as known compounds from this plant extract. The structures of the isolated compounds were elucidated by spectroscopic methods, including one- and two- dimensional 1H- and 13C-NMR and MS spectroscopies. The selected compounds were tested for antimicrobial activity against standard bacterial strains, and only carnosic acid 12-methyl ether showed antimicrobial activity against S. aureus at 78 microg mL(-1).  相似文献   

10.
Re-investigation of the methanolic extract of the sponge Diacarnus megaspinorhabdosa afforded one new norsesterpene cyclic peroxide diacarperoxide S (2), in addition to two known compounds sigmosceptrellin B (1) and nebularine (3). The structures of the isolated compounds were established on the basis of one and two dimensional NMR spectroscopic studies (1H, 13C, DEPT, COSY, HMQC, HMBC, and ROESY) as well as on mass spectral analysis. The isolated compounds were evaluated for their cytotoxic as well as antimicrobial activities.  相似文献   

11.
Phytochemical investigation of the roots of Patrinia rupestris afforded a new triterpenoid patrirupin A ( 1 ) and a new iridoid patrirupin B ( 2 ), as well as three known triterpenoids: 3‐oxo‐olean‐12‐en‐28‐oic acid ( 3 ), ursolic acid ( 4 ), α‐amyrin ( 5 ), three known iridoids: isovaltratum ( 6 ), 11‐ethoxyviburtinal ( 7 ), homobaldrinal ( 8 ), five known steroids: ergosterol ( 9 ), ergost‐6,22‐diene‐3β,5α,8α‐triol ( 10 ), 6‐hydroxenone ( 11 ), β‐sitosterol ( 12 ), daucosterol ( 13 ), and two known flavones: 1‐hydroxy‐5‐methoxy xanthen‐9‐one ( 14 ), 3′,4′,5,7‐tetrahydroxyflavanone ( 15 ). The new compounds were characterized by means of spectroscopic methods including UV, IR, 1D, 2D NMR and HRESIMS, and the known ones were established on the basis of comparing their NMR data with those of the corresponding compounds in the literature.  相似文献   

12.
From the ethanolic extract of Quercus glauca, two new lignans, (+)-5'-methoxyisolariciresinol-9'-O-α-L-rhamnopyranoside (1) and (7R,8S)-dihydrodehydrodiconiferyl alcohol 4-β-D-xyloside (2), along with fourteen known compounds including four lignanoids (3-6), five triterpenoids (7-11), two flavonoids (12, 13), two aromatics (14, 15), and one steroid (16) were isolated. The structures of the new compounds were elucidated on the basis of spectroscopic analysis. Moreover, compounds 9 and 14 strongly inhibited nitric oxide (NO) production with IC50 values of 8.25 and 14.04?μM, respectively, and compounds 1, 4-6, 14, and 15 showed moderate antioxidant activities.  相似文献   

13.
Phytochemical investigation of the EtOH extract of Clausena vestita D. D. Tao led to the isolation of one new coumarin, clauslactone U ( 1 ), and one new carbazole alkaloid, clauszoline N ( 2 ), together with 28 known compounds. The structures of these compounds were established by using MS and 1D‐ and 2D‐NMR techniques, and by comparison with known analogues.  相似文献   

14.
Two new N‐isobutylamides, hydroxy lanyuamide I ( 1 ) and hydroxy lanyuamide II ( 2 ), together with one hundred and ten known compounds, have been isolated from the root bark of Formosan Zanthoxylum ailanthoides. These known compounds include twenty coumarins, twenty‐one benzo[c]phenanthridines, ten quinoline derivatives, one aporphine, one purine, seven amides, twelve benzenoids, one lactone, four flavonoids, nine lignans, eight steroids, two chlorophylls, eleven terpenoids and three other compounds, which were determined by means of spectral analyses.  相似文献   

15.
The investigation of the chemical constituents of Symplocos racemosa Roxb led to the isolation of two new glycosides, symcomoside A (1) and symcomoside B (2), together with one known glycoside, tortoside C (3), which is reported for the first time from this plant. The structures of the new compounds were determined by 1D and 2D homonuclear and heteronuclear NMR spectroscopy, from chemical evidence and by comparison with published data for closely related compounds. Symcomoside B (2) showed potent inhibitory activity against alpha-glucosidase in a concentration-dependent fashion with an IC50 value of 0.733 +/- 0.033 mM whereas symcomoside A (1) showed very weak inhibitory activity against alpha-glucosidase (9.90% in 0.70 mM).  相似文献   

16.
Two new iridoids, named patridoid I (1) and patridoid II (2), were isolated from the whole plant of Patrinia saniculaefolia (Valerianaceae), together with the known one, nardostachin (3). The structures of compounds 1 and 2 were established on the basis of spectroscopic methods, including two dimensional (2D NMR) and high resolution fast atom bombardment mass spectrometry (HR-FAB-MS).  相似文献   

17.
Two new flavanones, (2S)-pinocembrin 7-O-[beta-D-apiosyl(1-->2)]-beta-D-glucoside (1), and (2S)-pinocembrin 7-O-[cinnamoyl(1-->5)-beta-D-apiosyl(1-->2)]-beta-D-glucoside (2) together with eighteen known compounds, which include five known flavanones, nine benzenoids, one inositol and three triterpenoids, were isolated and characterized from fresh Viscum articulactum. Structures of new compounds were determined by spectral analysis. Among them, oleanolic acid (18) showed a significant inhibition effect on superoxide anion generation by human neutrophils in response to formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP).  相似文献   

18.
From the roots of Saliva caespitosa Montbret and Aucher ex. Bentham a new diterpene 6beta-hydroxyisopimaric acid (1) has been isolated together with four known diterpenes, one new triterpenoid, 3-acetylvergatic acid (2), as well as five known triterpenoids, two steroids and a flavone. The structures of the compounds were established by spectroscopic analyses. The isolated compounds were tested against standard bacterial strains. Only the new diterpene, 6beta-hydroxyisopimaric acid has strong activity (MIC 9 microg/ml) against S. aureus and (MIC 18 microg/ml) against S. epidermidis as well as against B. subtilis (MIC 9 microg/ml).  相似文献   

19.
Two new guaianolides, 8alpha-hydroxy-11alpha,13-dihydroglucozaluzanin C and 11alpha,13-dihydroglucozaluzanin C, were isolated from Ainsliaea fragrans, along with two known guaianolides, 8alpha-hydroxy-11alpha,13-dihydrozaluzanin C and glucozaluzanin C. The structures of the new compounds were unambiguously established by HR-ESI-MS, one-dimensional (1D) (DEPT), two-dimensional (2D) ((1)H-(1)H COSY, HSQC, HMBC, ROESY) NMR experiments and by comparison with structurally related compounds. The known compounds were identified by comparison of spectral data with published references. Some NMR data of the known compounds were reported for the first time.  相似文献   

20.
Three new compounds, including two phenylacetic acid derivatives, monaspilosin (1) and monaspiloindole (2), and one pyranoindole alkaloid, monaspyranoindole (3), were isolated from the EtOAc-soluble fraction of the MeOH extract of the mycelia of Monascus pilosus BCRC 38072. Twelve known compounds were also obtained in this study. The structures were elucidated by 1D and 2D NMR spectroscopy and mass spectrometry. This is the first report of Monascus metabolites with an indole ring. All isolates were also evaluated for their scavenging properties toward the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) in TLC autographic and spectroscopic assays.  相似文献   

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