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1.
A further phytochemical investigation on the whole plants of Ypsilandra thibetica yielded three new spirostane glycosides, named ypsilandrosides M–O ( 1 – 3 ). Their structures were established as (3β,11α,25R)‐3,11‐dihydroxyspirost‐5‐en‐12‐one 3‐{O‐α‐L ‐rhanmopyranosyl‐(1→4)‐O‐L ‐rhanmopyranosyl‐(1→4)‐O‐[α‐L ‐rhanmopyranosyl‐(1→2)]‐β‐D ‐glucopyranoside} ( 1 ), (3β,7β,25R)‐spirost‐5‐ene‐3,7‐diol 3‐{O‐α‐L ‐rhanmopyranosyl‐(1→4)‐Oα‐L ‐rhanmopyranosyl‐(1→4)‐O‐[α‐L ‐rhanmopyranosyl‐(1→2)]‐β‐D ‐glucopyranoside} ( 2 ), and (3β,7α,25R)‐spirost‐5‐ene‐3,7,17‐triol 3‐{O‐α‐L ‐rhanmopyranosyl‐(1→4)‐Oα‐L ‐rhanmopyranosyl‐(1→4)‐O‐[α‐L ‐rhanmopyranosyl‐(1→2)]‐β‐D ‐glucopyranoside} ( 3 ) by means of a combination of MS, 1D‐ and 2D‐NMR spectroscopic methods, and chemical degradation. Among them, compound 3 is the first pennogenin (=(3β,25R)‐spirost‐5‐ene‐3,17‐diol) saponin whose aglycone contains an OH group at C(7). Compounds 1 – 3 were evaluated for the inhibition of the growth of five tumor cell lines, but all of them proved to be inactive.  相似文献   

2.
Three new dammarane‐type triterpene saponins, 1 – 3 , together with three known compounds, 4 – 6 , were isolated from the aerial parts of Gynostemma pentaphyllum (Thunb.) Makino . By means of chemical and spectroscopic methods, their structures were established as (20S)‐3β,20,21‐trihydroxydammara‐23,25‐diene 3‐O‐[α‐L ‐rhamnopyranosyl‐(1→2)] [β‐D ‐xylopyranosyl‐(1→3)]‐β‐D ‐glucopyranosyl‐21‐Oβ‐D ‐glucopyranoside ( 1 ), (20R,23R)‐3β,20‐dihydroxy‐19‐oxodammar‐24‐en‐21‐oic acid 21,23‐lactone 3‐O‐[α‐L ‐rhamnopyranosyl‐(1→2)] [β‐D ‐xylopyranosyl‐(1→3)]‐α‐L ‐arabinopyranoside ( 2 ), and (21S,23S)‐3β,20ξ,21,26‐tetrahydroxy‐19‐oxo‐21,23‐epoxydammar‐24‐ene 3‐O‐[α‐L ‐rhamnopyranosyl‐(1→2)] [β‐D ‐xylopyranosyl‐(1→3)]‐α‐L ‐arabinopyranoside ( 3 ).  相似文献   

3.
Four new saponins, yemuosides YM17–YM20 ( 1 – 4 , resp.), were isolated from the rattan of Stauntonia chinensis DC. (Lardizabalaceae) along with a known saponin, nipponoside D ( 5 ). Their structures were elucidated by spectroscopic analysis and chemical evidence as 20,30‐dihydroxy‐29‐noroleanolic acid 28‐Oα‐L ‐rhamnopyranosyl‐(1→4)‐β‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐glucopyranosyl ester ( 1 ), 20,29‐dihydroxy‐30‐noroleanolic acid 28‐Oα‐L ‐rhamnopyranosyl‐(1→4)‐β‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐glucopyranosyl ester ( 2 ), 29‐hydroxy‐30‐norolean‐20(21)‐enolic acid 28‐Oα‐L ‐rhamnopyranosyl‐(1→4)‐β‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐glucopyranosyl ester ( 3 ), 29‐hydroxyoleanolic acid 28‐Oα‐L ‐rhamnopyranosyl‐(1→4)‐β‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐glucopyranosyl ester ( 4 ), and 23,29‐dihydroxyoleanolic acid 28‐Oα‐L ‐rhamnopyranosyl‐(1→4)‐β‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐glucopyranosyl ester ( 5 ). Yemuoside YM17–YM19 ( 1 – 3 , resp.) contain novel unusual nortriterpene aglycones.  相似文献   

4.
Phytochemical investigation of the 95% EtOH extract of the dry fronds of Conyza japonica (Thunb .) Less. resulted in the isolation of three new labdane diterpene glycosides, (3β,13S)‐13‐Oα‐L ‐rhamnopyranosyllabda‐8(17),14‐dien‐3‐yl α‐L ‐rhamnopyranoside ( 1 ), (3β,13S)‐13‐Oα‐L ‐rhamnopyranosyllabda‐8(17),14‐diene‐3‐yl 2‐O‐acetyl‐α‐L ‐rhamnopyranoside ( 2 ), and (3β,13S)‐13‐Oα‐L ‐rhamnopyranosylabda‐8(17),14‐dien‐3‐yl 6‐O‐acetyl‐β‐D ‐glucopyranosyl‐(1→2)‐α‐L ‐rhamnopyranoside ( 3 ), together with their aglycone, (13S)‐labda‐8(17),14‐diene‐3,13‐diol ( 4 ). Their structures were characterized by spectroscopic analyses and chemical correlations, including 1D‐ and 2D‐NMR, and HR‐ESI‐MS. Furthermore, compounds 1 – 3 appeared to be promising as active agents against the tested pathogen fungi and oral pathogens as they possessed moderate cytotoxic properties.  相似文献   

5.
A chemical investigation of Lysimachia christinae, a traditional Chinese medicine used as an effective conservative treatment for gall stones, hepatolithiasis, and urinary calculi, resulted in the isolation of two new flavonoids, myricetin 3,3′‐di‐α‐L ‐rhamnopyranoside ( 1 ) and quercetin 3,3′‐di‐α‐L ‐rhamnopyranoside ( 2 ), along with the five known flavonoids quercetin 3‐[Oα‐L ‐rhamnopyranosyl‐(1→2)‐β‐D ‐galactopyranoside], amentoflavone, hyperin, quercetin 3‐β‐D ‐glucopyranoside, and kaempferol 3‐α‐L ‐rhamnopyranoside. Amentoflavone was reported for the first time from the genus Lysimachia, and quercetin 3‐[Oα‐L ‐rhamopyranosyl‐(1→2)‐β‐D ‐galactopyranoside] was isolated from this plant for the first time. The structures of the new compounds were elucidated on the basis of their chemical reactions and extensive spectroscopic analyses, including UV, mass, and NMR spectra.  相似文献   

6.
Two new homo‐aro‐cholestane glycosides and a new cholestane glycoside, along with three known saponins, were isolated from the 95% EtOH extract of the roots and rhizomes of Paris polyphylla var. pseudothibetica. The structures of the new compounds were elucidated as 3βO‐{α‐L ‐rhamnopyranosyl‐(1→4)‐α‐L ‐rhamnopyranosyl‐(1→4)‐[α‐L ‐rhamnopyranosyl‐(1→2)]}‐β‐D ‐glucopyranosylhomo‐aro‐cholest‐5‐ene‐26‐Oβ‐D ‐glucopyranoside (parispseudoside A, 1 ), 3βOα‐L ‐rhamnopyranosyl‐(1→2)‐β‐D ‐glucopyranosylhomo‐aro‐cholest‐5‐ene‐26‐Oβ‐D ‐glucopyranoside (parispseudoside B, 2 ), and (25R)‐3βO‐{α‐L ‐rhamnopyranosyl‐(1→4)‐α‐L ‐rhamnopyranosyl‐(1→4)‐[α‐L ‐rhamnopyranosyl‐(1→2)]}‐β‐D ‐glucopyranosyl‐cholesta‐5,17(20)‐diene‐16,22‐dione‐26‐Oβ‐D ‐glucopyranoside (parispseudoside C, 3 ) by spectroscopic methods, including 1D‐ and 2D‐NMR, and MS experiments, as well as chemical evidences.  相似文献   

7.
Two new phenolic compounds, (Z)‐5′‐hydroxyjasmone 5′‐O‐{6″‐O‐[(E)‐caffeoyl]‐β‐D ‐glucopyranoside} ( 1 ) and quercetin‐7‐Oβ‐D ‐glucuronide methyl ester ( 2 ), along with ten known phenolic compounds, 3 – 12 , were isolated from the aerial parts of Artemisia iwayomogi. Their structures were elucidated by spectroscopic methods, including 1D‐ and 2D‐NMR, and HR‐ESI‐TOF‐MS techniques. The inhibitory effects of compounds 1 – 12 on the LPS‐stimulated production of IL‐12 p40, IL‐6, and TNF‐α in bone marrow‐derived dendritic cells were evaluated.  相似文献   

8.
Periplocain A ( 2 ), a new naphthalene derivative together with four known compounds: 2‐ethylhexyl benzoate ( 1 ), quercetin‐3‐Oα‐l ‐rhamnopyranoside ( 3 ), quercetin‐3‐Oβ‐d ‐glucopyranoside ( 4 ), and quercetin‐3‐(6‐Oα‐l ‐rhamnopyranosyl‐β‐d ‐glucopyranoside) ( 5 ) were isolated from the AcOEt fraction of the aerial parts of Periploca aphylla (Asclepiadaceae). Their structures were established by multiple spectroscopic methods in addition to HR‐ESI‐MS and by comparison with literature data.  相似文献   

9.
Five new triterpene saponins 1 – 5 were isolated from the roots of Muraltia ononidifolia E. Mey along with the two known saponins 3‐O‐[Oβ‐D ‐glucopyranosyl‐(1→2)‐β‐D ‐glucopyranosyl]medicagenic acid 28‐[Oβ‐D ‐xylopyranosyl‐(1→4)‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐α‐L ‐arabinopyranosyl] ester and 3‐O‐(β‐D ‐glucopyranosyl)medicagenic acid 28‐[Oα‐L ‐rhamnopyranosyl‐(1→2)‐α‐L ‐arabinopyranosyl] ester (medicagenic acid=(4α,2β,3β)‐2,3‐dihydroxyolean‐12‐ene‐23,28‐dioic acid). Their structures were elucidated mainly by spectroscopic experiments, including 2D‐NMR techniques, as 3‐O‐(β‐D ‐glucopyranosyl)medicagenic acid 28‐[Oβ‐ D ‐apiofuranosyl‐(1→3)‐Oβ‐D ‐xylopyranosyl‐(1→4)‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐α‐L ‐arabinopyranosyl] ester ( 1 ), 3‐O‐(β‐D ‐glucopyranosyl)medicagenic acid 28‐{[Oβ‐D ‐xylopyranosyl‐(1→4)‐O‐[β‐D ‐apiofuranosyl‐(1→3)]‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐α‐L ‐arabinopyranosyl} ester ( 2 ), 3‐O‐[Oβ‐D ‐glucopyranosyl‐(1→2)‐β‐D ‐glucopyranosyl]medicagenic acid 28‐{Oβ‐D ‐xylopyranosyl‐(1→4)‐O‐[β‐D ‐apiofuranosyl‐(1→3)]‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐α‐L ‐arabinopyranosyl} ester ( 3 ), 3‐O‐[Oβ‐D ‐glucopyranosyl‐(1→2)‐β‐D ‐glucopyranosyl]medicagenic acid 28‐[Oα‐L ‐rhamnopyranosyl‐(1→2)‐α‐L ‐arabinopyranosyl] ester ( 4 ), and 3‐O‐[Oβ‐D ‐glucopyranosyl‐(1→2)‐β‐D ‐glucopyranosyl]medicagenic acid ( 5 ).  相似文献   

10.
A new triterpene, (3β,12β)‐taraxast‐20(30)‐ene‐3,12‐diol (=(3β,12β,18α,19α)‐urs‐20(30)‐ene‐3,12‐diol; 1 ), together with the known compounds ursolic acid, α‐amyrin, β‐amyrin, (2α,3β)‐2,3‐dihydroxyursa‐5,12‐dien‐28‐oic acid, (2α,3β)‐2,3,23‐trihydroxyurs‐12‐en‐28‐oic acid, (2S,3S,4R,8Z)‐1‐O‐(β‐D ‐glucopyranosyl)‐2‐{[(2R)‐2‐hydroxydocosanoyl]amino}octadec‐8‐ene‐1,3,4‐triol, and (2S,3S,4R,8Z)‐1‐O‐(β‐D ‐glucopyranosyl)‐2‐[(palmitoyl)amino]octadec‐8‐ene‐1,3,4‐triol, and quercetin 3‐(β‐D ‐glucopyranoside) were isolated from the leaves of Craibiodendron yunnanense. Their structures were established on the basis of spectral evidence. The last four compounds were identified for the first time in this plant.  相似文献   

11.
The four new acylated triterpene saponins 1 – 4 , isolated as two pairs of isomers and named libericosides A1/A2 and B1/B2, one pair of isomers 5 / 6 , the (Z)‐isomer libericoside C2 ( 5 ) being new, one new sucrose ester, atroximoside ( 7 ), and eight known compounds were isolated from the roots of Atroxima liberica by repeated MPLC and VLC on normal and reversed‐phase silica gel. Their structures were elucidated on the basis of extensive 1D‐ and 2D‐NMR studies (1H‐ and 13C‐NMR, DEPT, COSY, TOCSY, NOESY, HSQC, and HMBC) and mass spectrometry as 3‐Oβ‐D ‐glucopyranosylpresenegenin 28‐{Oα‐L ‐arabinopyranosyl‐(1→3)‐Oβ‐D ‐xylopyranosyl‐(1→4)‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐4‐O‐[(E)‐3,4‐dimethoxycinnamoyl]‐β‐D ‐fucopyranosyl} ester ( 1 ) and its (Z)‐isomer 2 , 3‐Oβ‐D ‐glucopyranosylpresenegenin 28‐{Oα‐L ‐arabinopyranosyl‐(1→4)‐Oβ‐D ‐xylopyranosyl‐(1→4)‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐O‐[O‐β‐D ‐xylopyranosyl‐(1→3)‐β‐D ‐glucopyranosyl‐(1→3)]‐4‐O‐[(E)‐3,4‐dimethoxycinnamoyl]‐β‐D ‐fucopyranosyl} ester ( 3 ) and its (Z)‐isomer 4 , 3‐Oβ‐D ‐glucopyranosylpresenegenin 28‐{Oβ‐D ‐xylopyranosyl‐(1→4)‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐O‐[6‐O‐acetyl‐β‐D ‐glucopyranosyl‐(1→3)]‐4‐O‐[(Z)‐3,4‐dimethoxycinnamoyl]‐β‐D ‐fucopyranosyl} ester ( 5 ), and 3‐O‐[(Z)‐feruloyl]‐β‐D ‐fructofuranosyl α‐D ‐glucopyranoside ( 7 ). Compounds 1 – 6 and the known saponins 8 / 9 were evaluated against the human colon cancer cells HCT 116 and HT‐29 and showed moderate to weak cytotoxicity.  相似文献   

12.
Three new pregnane glycosides, cynatroside A ( 1 ), cynatroside B ( 2 ), and cynatroside C ( 3 ), isolated from the roots of Cynanchum atratum (Asclepiadaceae), were characterized as 7β‐{[Oα‐L ‐cymaropyranosyl‐(1→4)‐Oβ‐D ‐digitoxopyranosyl‐(1→4)‐β‐D ‐oleandropyranosyl]oxy}‐3,4,4a,4b,5,6,7,8,10,10a‐decahydro‐6α‐hydroxy‐4b‐ methyl‐2‐(2‐methyl‐3‐furyl)phenanthren‐1(2H)‐one ( 1 ), 7β‐{[Oβ‐D ‐cymaropyranosyl‐(1→4)‐Oα‐L ‐diginopyranosyl‐(1→4)‐β‐D ‐cymaropyranosyl]oxy}‐3,4,4a,4b,5,6,7,8,10,10a‐decahydro‐2,6α‐dihydroxy‐4b‐methyl‐2‐(2‐methyl‐3‐furyl)phenanthren‐1(2H)‐one ( 2 ), and 7β‐{[Oα‐L ‐cymaropyranosyl‐(1→4)‐Oβ‐D ‐digitoxopyranosyl‐(1→4)‐β‐L ‐cymaropyranosyl]oxy}‐3,4,4a,4b,5,6,7,8,10,10a‐decahydro‐2,6α‐dihydroxy‐4b‐methyl‐2‐(2‐methyl‐3‐furyl)phenanthren‐1(2H)‐one ( 3 ), respectively. In addition, ten known constituents were identified, i.e., cynascyroside D ( 4 ), glaucoside C ( 5 ), glaucoside D ( 6 ), atratoside A ( 7 ), 2,4‐dihydroxyacetophenone ( 8 ), 4‐hydroxyacetophenone ( 9 ), syringic acid ( 10 ), azelaic acid ( 11 ), suberic acid ( 12 ), and succinic acid ( 13 ). Among these compounds, 1 – 4 significantly inhibit acetylcholinesterase activity.  相似文献   

13.
The hydroalcoholic (EtOH/H2O) extract of matured leaf margins of lemon balm (Melissa officinalis L.) afforded a new 3,23‐disulfate of 2α,3β‐23,29‐tetrahydroxyolean‐12‐en‐28‐oic acid 28‐Oβ‐D ‐glucopyranoside ( 1 ) and a new 23‐monosulfate of 2α,23‐dihydroxyurs‐12‐en‐28‐oic acid 3‐Oβ‐D ‐glucopyranoside ( 2 ), along with six known compounds, i.e., 23‐monosulfate of 2α,3β,19α,23‐tetrahydroxyurs‐12‐ene‐28‐oic acid 28‐Oβ‐D ‐glucopyranoside ( 3 ), 3,5,6‐trihydroxydehydro‐α‐ionol 9‐Oβ‐D ‐glucopyranoside ( 4 ), quadranoside III ( 5 ), rosmarinic acid ( 6 ), caffeic acid ( 7 ), and luteolin ( 8 ). All the isolated compounds were evaluated for their antioxidant, antimicrobial, antimalarial, and cytotoxic activities. Only rosmarinic acid exhibited substantial antioxidant and antimicrobial activities, whereas sulfated terpenes showed considerably lower or no antimicrobial activity.  相似文献   

14.
Two new compounds, (6S,13S)‐6‐{[β‐D ‐glucopyranosyl‐(1→4)‐α‐L ‐rhamnopyranosyl]oxy}cleroda‐3,14‐dien‐13‐ol ( 1 ) and kadsuric acid 3‐methyl ester ( 2 ), together with nine known compounds, (6S,13E)‐6‐{[β‐D ‐glucopyranosyl‐(1→4)‐α‐L ‐rhamnopyranosyl]oxy}cleroda‐3,13‐dien‐15‐ol ( 3 ), (6S,13S)‐6‐[6‐O‐acetyl‐β‐D ‐glucopyranosyl‐(1→4)‐α‐L ‐rhamnopyranosyl]oxy}‐13‐{[α‐L ‐rhamnopyranosyl‐(1→4)‐β‐D ‐fucopyranosyl]oxy}cleroda‐3,14‐diene ( 4 ), (6S,13S)‐6‐{[6‐Oβ‐D ‐glucopyranosyl‐(1→4)‐α‐L ‐rhamnopyranosyl]oxy}‐13‐{[α‐L ‐rhamnopyranosyl‐(1→4)‐β‐D ‐fucopyranosyl]oxy}cleroda‐3,14‐diene ( 5 ), 15‐hydroxydehydroabietic acid ( 6 ), 15‐hydroxylabd‐8(17)‐en‐19‐oic acid ( 7 ), junicedric acid ( 8 ), (4β)‐kaur‐16‐en‐18‐oic acid ( 9 ), (4β)‐16‐hydroxykauran‐18‐oic acid ( 10 ), and (4β,16β)‐16‐hydroxykauran‐18‐oic acid ( 11 ) were isolated from the fronds of Dicranopteris linearis or D. ampla. Their structures were established by extensive 1D‐ and 2D‐NMR spectroscopy. Compounds 1 and 3 – 8 showed no anti‐HIV activities.  相似文献   

15.
Three new, 1 – 3 , and seven known phenolic and terpenic glycosides were isolated from the BuOH‐soluble fraction of 95% EtOH extract of the roots and rhizomes of Celastrus orbiculatus. The structures of the new compounds were elucidated as carvacrol 2‐Oα‐L ‐rhamnopyranosyl‐(1→6)‐β‐D ‐glucopyranoside ( 1 ), 5‐methoxycarvacrol 2‐Oα‐L ‐rhamnopyranosyl‐(1→6)‐β‐D ‐glucopyranoside ( 2 ), and 15‐hydroxytorreyol 10‐Oβ‐D ‐apiofuranosyl‐(1→6)‐β‐D ‐glucopyranoside ( 3 ) on the basis of spectroscopic analysis and chemical methods.  相似文献   

16.
Phytochemical investigation of the leaves of Phragmanthera capitata collected on Cassia spectabilis tree led to the isolation of two natural lactones, rel‐(1R,5S,7S)‐7‐[2‐(4‐hydroxyphenyl)ethyl]‐2,6‐dioxabicyclo[3.3.1]nonan‐3‐one ( 1 ) and 4‐{2‐[rel‐(1R,3R,5S)‐7‐oxo‐2,6‐dioxabicyclo[3.3.1]non‐3‐yl]ethyl}phenyl 3,4,5‐trihydroxybenzoate ( 2 ) together with the known compounds betulinic acid ( 3 ), dodoneine ( 4 ), quercetin 3‐Oα‐L ‐rhamnopyranoside ( 5 ), quercetin 3‐Oα‐L ‐arabinofuranoside ( 6 ), quercetin ( 7 ), betulin ( 8 ), lupeol ( 9 ), and sitosterol ( 10 ). Their structures were established by means of modern spectroscopic techniques, and the relative configuration of compound 1 was confirmed by X‐ray analysis. Compounds 1 and 2 were tested in vitro for their antiplasmodial activity against the Plasmodium falciparum chloroquine sensitive‐strains NF54 and 3D7. Compound 2 exhibited good antiplasmodial activity against both strains with IC50 of 2.4 and 4.9 μM , respectively, while compound 1 was inactive.  相似文献   

17.
Three new kaempferol glycosides, kaempferol 3‐Oβ‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐galactopyranosyl‐7‐Oα‐L ‐rhamnopyranoside ( 1 ), kaempferol 3‐O‐β‐D ‐galactopyranosyl‐7‐Oβ‐D ‐glucopyranosyl‐(1→3)‐α‐L ‐rhamnopyranoside ( 2 ), and kaempferol 3‐Oβ‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐galactopyranosyl‐7‐Oβ‐D ‐glucopyranosyl‐(1→3)‐α‐L ‐rhamnopyranoside ( 3 ), were isolated from the whole herbs of Cardamine leucantha, along with three known kaempferol glycosides, kaempferol 7‐Oα‐L ‐rhamnopyranoside, kaempferitrin, and kaempferol 3‐Oβ‐D ‐galactopyranosyl‐7‐Oα‐L ‐rhamnopyranoside. Their structures were elucidated on the basis of spectroscopic methods.  相似文献   

18.
Three new compounds, myrsinoside A (=2,4‐dihydroxy‐6‐methylphenyl β‐D ‐(6′‐galloyl)glucopyranoside; 1 ), myrsinoside B (2,4‐dihydroxy‐6‐methylphenyl β‐D ‐glucopyranoside; 2 ), and (3β,16α,20α)‐3,16,28‐trihydroxyolean‐12‐en‐29‐oic acid 3‐{Oβ‐D ‐glucopyranosyl‐(1→2)‐O‐[β‐D ‐glucopyranosyl‐(1→4)]‐α‐L ‐arabinopyranoside} ( 3 ), along with four known compounds, were isolated from the stems of Myrsine africana L. The structures of these new compounds were elucidated on the basis of spectroscopic analysis, including 1D‐ and 2D‐NMR and ESI‐MS techniques, and chemical methods.  相似文献   

19.
Four new compounds, 9α‐hydroxy‐1β‐methoxycaryolanol ( 1 ), stigmast‐5‐ene‐7α,22α‐diol‐3β‐tetradecanoate ( 2 ), 7‐O‐(6′‐acetoxy‐β‐D ‐glucopyranosyl)coumarin ( 3 ), and 8‐O‐(6′‐acetoxy‐β‐D ‐glucopyranosyl)‐7‐hydroxycoumarin ( 4 ), together with ten known compounds, were isolated from the aerial parts of Sinacalia tangutica. The structures of the new compounds were established by means of extensive spectroscopic analyses (1D‐ and 2D‐NMR, EI‐MS, HR‐ESI‐MS, as well as IR and UV) and by comparison of their spectroscopic data with those of structurally related compounds reported in the literature.  相似文献   

20.
Three new oleanane‐type triterpenoid saponins, 3‐O‐(α‐L ‐rhamnopyranosyl(1→2)‐β‐D ‐fucopyranosyl)‐28‐O‐{[α‐L ‐rhamnopyranosyl(1→2)] [β‐D ‐fucopyranosyl(1→6)]‐β‐D ‐glucopyranosyl} oleanolic acid ( 1 ), 3‐O‐[α‐L ‐rhamnopyranosyl(1→3)‐β‐D ‐fucopyranosyl]‐28‐O‐[α‐L ‐rhamnopyranosyl(1→4)‐β‐D ‐glucopyranosyl] oleanolic acid ( 2 ), and 3‐O‐{α‐L ‐rhamnopyranosyl(1→2)‐[3′,4′‐diacetoxy‐β‐D ‐fucopyranosyl]}‐28‐O‐[α‐L ‐rhamnopyranosyl(1→2)‐β‐D ‐glucopyranosyl] oleanolic acid ( 3 ) have been isolated from the stems of Xerospermum noronhianum. The structures of the saponins were determined as a series of bidesmosidic oleanane saponins based on spectral evidence. The anticholinesterase activity of the saponins 1 – 3 was also evaluated.  相似文献   

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