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1.
The isolation and structure elucidation of a new triterpenic acid named floccosic acid ( 1 ) is reported on the basis of the 1D‐ and 2D‐NMR assignments. This secondary metabolite was isolated as a new constituent, along with the known triterpenoids, betulinic acid and β‐amyrin. All these compounds were purified by repeated column chromatography of the MeOH extract of Nepeta floccosa. The structure elucidation of the new compound was accomplished by the combined mass spectrometry (MS), infrared (IR) and ultraviolet (UV) absorption spectroscopy, one‐ (1H‐ and 13C‐) and two‐dimensional (H? C correlations; HMBC and HSQC) NMR techniques. The known compounds were identified by comparison of their physical and spectroscopic data with those reported in the literature.  相似文献   

2.
The phytochemical studies on the leaves of the traditionally used medicinal plant Combretum fragrans F. Hoffm (Combretaceae) from Cameroon have led to the isolation of combretins A and B ( 1 and 2 , resp.), two new cycloartane‐type triterpenes from the AcOEt‐soluble subfraction along with β‐sitosterol ( 3 ), oleanolic acid ( 4 ), ursolic acid ( 5 ), and pratensein ( 6 ). The compounds 4  –  6 are reported for the first time from this species. The structures of the new triterpenes were elucidated by spectroscopic techniques including 1H‐ and 13C‐NMR (DEPT), and 2D‐NMR experiments.  相似文献   

3.
Two new perulactone‐type withanolides, named perulactone C ( 1 ) and perulactone D ( 2 ), together with four known compounds, perulactone ( 3 ), perulactone B ( 4 ), blumenol A, and (+)‐(S)‐dehydrovomifoliol, were isolated from the aerial parts of Physalis peruviana. The structures of the new compounds were elucidated on the basis of 1D‐ and 2D‐NMR experiments, including HMBC, HSQC, 1H,1H‐COSY, and ROESY, as well as HR‐MS.  相似文献   

4.
Three new pentacyclic triterpenoids, camarin ( 1 ), lantacin ( 2 ), and camarinin ( 3 ) were isolated from the aerial parts of Lantana camara Linn ., together with seven known compounds. The structures of the new constituents were elucidated by chemical transformation, HR‐EI mass spectrometry, and NMR spectroscopy, including 1D (1H‐ and 13C‐NMR) and 2D (1H,1H‐COSY, NOESY, 1H,1H‐TOCSY, J‐resolved, HMQC, and HMBC) experiments.  相似文献   

5.
Four new triterpenoid glycosides named asiaticoside C ( 1 ), D ( 2 ), E ( 3 ), and F ( 4 ) were isolated from the BuOH fraction of the EtOH extract of whole plants of Centella asiatica, together with three known compounds, asiaticoside ( 5 ), madecassoside ( 6 ), and scheffuroside B ( 7 ). Based on FAB‐MS, IR, 1H‐ and 13C‐NMR, and 2D‐NMR data (HMQC, HMBC, COSY), the structures of the new compounds were determined as (2α,3β,4α)‐23‐(acetyloxy)‐2,3‐dihydroxyurs‐12‐en‐28‐oic acid Oα‐L ‐rhamnopyranosyl‐(1→4)‐Oβ‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐glucopyranosyl ester ( 1 ), (2α,3β)‐2,3‐dihydroxyurs‐12‐en‐28‐oic acid Oα‐L ‐rhamnopyranosyl‐(1→4)‐Oβ‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐glucopyranosyl ester ( 2 ), asiatic acid 6‐Oβ‐D ‐glycopyranosyl‐β‐D ‐glucopyranosyl ester ( 3 ), (3β,4α)‐3,23‐dihydroxyurs‐12‐en‐28‐oic acid Oα‐L ‐rhamnopyranosyl‐(1→4)‐Oβ‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐glucopyranosyl ester ( 4 ).  相似文献   

6.
One new cyclopropyl‐triterpenoid ( 1 ), along with four known constituents including octacosan‐1‐ol ( 2 ), pentacosanoic acid ( 3 ), β‐sitosterol ( 4 ), and β‐sitosterol 3‐Oβ‐D ‐glucopyranoside ( 5 ) were isolated from the aerial parts of Ochradenus arabicus for the first time. These compounds were isolated by repeated column chromatography followed by further purification through recycling HPLC. The structure of the new secondary metabolite 1 was established on the basis of UV, IR, 1D‐ (1H‐ and 13C‐) and 2D‐NMR (HMBC and HSQC), and MS spectral data. The molecular mass was determined by HR‐MS, and hence the molecular formula was deduced. The configurations of stereogenic centers in the molecule were assigned by NOESY experiments, along with biogenetic considerations. The structures of the known compounds were confirmed by comparison of their physical and spectroscopic data with those reported in literature.  相似文献   

7.
Two new iridoids, 6‐O‐[(E)‐feruloyl]jioglutin D ( 1 ) and 6‐O‐(4‐hydroxybenzoyl)jioglutin D ( 2 ), and six known compounds, minecoside ( 3 ), specioside ( 4 ), picroside II ( 5 ), picroside III ( 6 ), 4‐hydroxybenzoic acid ( 7 ), and martynoside ( 8 ), were isolated from the stem of Catalpa ovata. The structures of the new compounds were established on the basis of spectroscopic techniques, including 1D‐ and 2D‐NMR.  相似文献   

8.
Phytochemical investigation of the stem bark of Acanthopanax brachypus afforded a new labdanetype diterpene glycoside, 3α‐trans‐sinapoyloxy‐jhanol 18‐O‐β‐D‐glucopyranoside ( 1 ), together with four known compounds, including one diterpene acid, acanthoic acid ( 2 ), one coumarin, isofraxidin ( 3 ), one phenolic glycoside, sasanquin ( 4 ), as well as one chalcone glycoside, okanin 4‐methyl ether‐3′‐O‐β‐D‐glucopyranoside ( 5 ). All of the structures were characterized by means of spectroscopic methods, including 1H, 13C, 2D‐NMR and HR‐MS, as well as chemical methods and comparison with the literature data.  相似文献   

9.
Bioassay‐guided fractionation of the active AcOEt‐soluble layer from the whole plant of Amischotolype hispida resulted in the isolation of four new compounds, i.e., amisbenzoic acid ( 1 ), one butenolide derivative, amisnolide ( 2 ), one chlorin analog, amisphytin ( 3 ), one lignan, amislignol ( 4 ), and one metabolite isolated for the first time from nature, (?)‐glaberide I ( 5 ), along with 20 known compounds, 6 – 25 . Their structures were elucidated on the basis of UV, IR, 1D‐ and 2D‐NMR (1H,1H‐COSY, DEPT, HSQC, HMBC), as well as HR‐ESI‐MS, analyses. Among these isolates, palmitic acid ( 13 ) showed an antimycobacterial activity with an MIC value of 20.0 μg/ml against Mycobacterium tuberculosis H37Rv.  相似文献   

10.
Three new caged prenylxanthones (xanthone=9H‐xanthen‐9‐one), named neobractatin ( 1 ), 3‐O‐methylneobractatin ( 2 ), and 3‐O‐methylbractatin ( 3 ), along with eight known compounds, were isolated from the twig of Garcinia bracteata. The structures of the new compounds were elucidated on the basis of 1D‐ and 2D‐NMR experiments, including HMBC, HSQC, 1H,1H‐COSY, and ROESY, as well as HR‐MS analysis.  相似文献   

11.
In present literature search, some cyano-containing compounds, which are very rare in plants, from the traditional anticancer herb Tiankuizi were reported. To find more cyano-containing compounds in the important plant Semiaquilegia adoxoides (DC) Makino (Chinese name Tiankuizi), the isolation of the chemical constituents was investigated for advancing the research. Two new compounds, a new alkaloid, 1,2,3,4-tetrahydro-6-hydroxy-1[(3,4-dihydroxyphenyl)methyl]-7-methoxy-2,2-dimethyl-isoquinolinium, named Semiaquilegine A (1), and a new ester, 3-(4'-hydroxyphenyl)-2-propenoic acid (4"-carboxyl)-phenyl ester (2), and four cyano-containing compounds, (Z)-6a-(β-D-glucosyloxy)-4a,5a-dihydroxy-2-cyclohexene-△^1,a-acetonitrile (3), (L0-6α-(β-D-glucosyloxy)-4α-hydroxy-2-cyclohexene-△^1,α-acetonitrile (4), lithospermoside (5), ehretioside B (6), as well as eleven known compounds, were isolated from the roots of Semiaquilegia adoxoides. The structures of new compounds 1 and 2 were elucidated mainly by 1D/2D-NMR techniques. Very unusual cyano-containing compounds 3 and 4 were first isolated from Ranunculaceae family. Hitherto, there were six cyano-containing compounds found in the herb.  相似文献   

12.
The chemical study of Sechium mexicanum roots led to the isolation of the two new saponins {3‐O‐β‐D ‐glucopyranosyl (1 → 3)‐β‐D ‐glucopyranosyl‐2β,3β,16α,23‐tetrahydroxyolean‐12‐en‐28‐oic acid 28‐O‐α‐L ‐rhamnopyranosyl‐(1 → 3)‐β‐D ‐xylopyranosyl‐(1 → 4)‐α‐L ‐rhamnopyranosyl‐(1 → 2)‐α‐L ‐arabinopyranoside} (1) and {3‐O‐β‐D ‐glucopyranosyl (1 → 3)‐β‐D ‐glucopyranosyl‐2β,3β,16α,23‐tetrahydroxyolean‐12‐en‐28‐oic acid 28‐O‐α‐L ‐rhamnopyranosyl‐(1 → 3)‐β‐D ‐xylopyranosyl‐(1 → 4)‐[β‐D ‐apiosyl‐(1 → 3)]‐α‐L ‐rhamnopyranosyl‐(1 → 2)‐α‐L ‐arabinopyranoside} (2), together with the known compounds {3‐O‐β‐D ‐glucopyranosyl‐(1 → 3)‐β‐D ‐glucopyranosyl‐2β,3β,6β,16α,23‐pentahydroxyolean‐12‐en‐28‐oic acid 28‐O‐α‐L ‐rhamnopyranosyl‐(1 → 3)‐β‐D ‐xylopyranosyl‐(1 → 4)‐α‐L ‐rhamnopyranosyl‐(1 → 2)‐α‐L ‐arabinopyranoside} (3), tacacosides A1 (4) and B3 (5). The structures of saponins 1 and 2 were elucidated using a combination of 1H and 13C 1D‐NMR, COSY, TOCSY, gHMBC and gHSQC 2D‐NMR, and FABMS of the natural compounds and their peracetylated derivates, as well as by chemical degradation. Compounds 1–3 are the first examples of saponins containing polygalacic and 16‐hydroxyprotobasic acids found in the genus Sechium, while 4 and 5, which had been characterized partially by NMR, are now characterized in detail. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

13.
Two new alkaloids, i.e., (2,3‐dihydro‐1‐oxo‐1H‐pyrrolo[1,2‐a]pyrrol‐7‐yl)methyl (2S*,3S*)‐3‐[(β‐D ‐glucopyranosyl)oxy]‐2‐hydroxy‐2‐(1‐methylethyl)butanoate ( 1 ) and 1,2‐dihydro‐8‐methoxy‐2‐oxoquinoline‐4‐carboxylic acid ( 2 ), were isolated from the alcoholic extract of the whole plant of Cynoglossum gansuense, together with twelve known compounds Their structures were characterized by means of spectroscopic methods, especially by 1H‐, 13C‐, and 2D‐NMR, as well as by HR‐MS experiments and comparison with literature data.  相似文献   

14.
Two new alkaloids, pegamine β‐D ‐glucopyranoside ( 1 ) and 2‐deoxypeganylacetic acid ( 2 ), together with the novel 3,4‐dihydro‐4‐hydroxynaphthalene‐2‐carboxylic acid ( 3 ), were isolated from the aerial part of Peganum nigellastrum. The structures of these compounds were elucidated on the basis of spectroscopic analyses, including 1D‐ and 2D‐NMR, and ESI‐MS/MS.  相似文献   

15.
Three new monoterpene alkaloids, mairine A ( 1 ), mairine B ( 2 ), and mairine C ( 3 ), and a new caffeic acid ester, 2‐(1‐hydroxy‐4,4‐dimethoxycyclohexyl)ethyl caffeate ( 4 ), were isolated from the EtOH extract of the whole plants of Incarvillea mairei var. multifoliolata. The structures of these compounds were established on the basis of 1D‐ and 2D‐NMR and HR‐ESI‐MS analysis.  相似文献   

16.
Two new 3,4‐seco‐cycloartane triterpenes, named sootepin F ( 1 ) and sootepin G ( 2 ), together with two known compounds, coronalolide methyl ester ( 3 ) and sootepin D ( 4 ), were isolated from the leaves and twigs of Gardenia sootepensis. Their structures were elucidated on the basis of 1D‐ and 2D‐NMR experiments, including HMBC, HSQC, 1H,1H‐COSY, and ROESY, as well as HR‐MS.  相似文献   

17.
Two new tetracyclic triterpenoids shiona‐19(E),21‐dien‐3β‐ol ( 1 ), and shiona‐22(29)‐en‐3β,21‐diol ( 2 ), together with four known compounds shiona‐21‐en‐3β‐ol ( 3 ), friedelinol ( 4 ), β‐sitosterol ( 5 ), and (24R)‐stigmast‐7,22(E)‐dien‐3a‐ol ( 6 ) were isolated from Aster ageratoides var. oophyllus. The structures of two new compounds were established on the basis of IR, MS, 1H, 13C and 2D NMR spectroscopic methods.  相似文献   

18.
Eight new metabolites, including five new sesquiterpenoids, 10,11‐epoxyguaian‐10‐ol ( 1 ), 10,11‐epoxyguaian‐13‐ol ( 2 ), a new backbone sesquiterpene rearranged from guaiane ( 3 ), two 1,5 : 1,10‐disecoguaianes, 4 and 5 , two new dihydroisocoumarins, 7‐chloromellein‐4‐ol ( 6 ) and 7‐chloromellein‐5‐ol ( 7 ), and one new tetralone, 7‐chloroscytalone ( 8 ), were isolated from the mutant strain G‐444 of Tubercularia sp. TF5, an endophytic fungus of Taxus mairei, along with ten known compounds, 3,4‐dihydro‐4,8‐dihydroxy‐2H‐naphthalen‐1‐one ( 9 ), (3R,4S)‐4‐hydroxymellein ( 10 ), 5‐formylmellein ( 11 ), 5‐carboxymellein ( 12 ), sporogen‐AO1 ( 13 ), tuberculariols A ( 14 ) and B ( 15 ), hymatoxin E ( 16 ), 4‐oxo‐4H‐pyran‐3‐acetic acid ( 17 ), and penicillic acid ( 18 ). Their structures were elucidated by spectroscopic analyses including HR‐ESI‐MS, 1D‐ and 2D‐NMR (HMQC, HMBC, 1H,1H‐COSY and NOESY). The antimicrobial activities of 1 – 8 were evaluated, but none showed any substantial effect.  相似文献   

19.
Three new 20,24‐epoxydammarane triterpenes, santolins A–C ( 1 – 3 ), were isolated from the AcOEt‐soluble fraction of the MeOH extract of Salvia santolinifolia (whole plant). Their structures were assigned based on 1H‐NMR, 13C‐NMR (DEPT), and 2D‐NMR analyses, in combination with HR‐MS experiments and comparison with literature data of related compounds.  相似文献   

20.
From the stem bark of Mangifera indica, seven cycloartane‐type secondary metabolites were isolated. Compound 1 has been isolated for the first time from M. indica, whereas compounds 2 (2a and 2b, as an epimeric mixture), 3, and 4 are new triterpenoid‐type cycloartanes. Unambiguous 13C and 1H NMR assignments for these compounds and the known compounds mangiferonic acid (compound 5), isomangiferolic acid (compound 6), ambolic acid (compound 7), and friedelin (compound 8) are reported; the latter because full NMR data for these compounds are not available in the literature. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

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