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1.
Three new furostanol glycosides, named ciliatasides A, B, and C ( 1 – 3 , resp.), have been isolated from the roots of Digitalis ciliata, along with two known furostanol glycosides. The structures of the new compounds were identified as (2α,3β,5α,14β,25R)‐26‐(β‐D ‐glucopyranosyloxy)‐2‐hydroxyfurost‐20(22)‐en‐3‐yl β‐D ‐glucopyranosyl‐(1→2)‐[β‐D ‐glucopyranosyl‐(1→3)]‐β‐D ‐galactopyranoside ( 1 ), (2α,3β,5α,14β,22R)‐26‐(β‐D ‐glucopyranosyloxy)‐2‐hydroxy‐22‐methoxyfurost‐25(27)‐en‐3‐yl β‐D ‐galactopyranosyl‐(1→2)‐[β‐D ‐xylopyranosyl‐(1→3)]‐β‐D ‐glucopyranosyl‐(1→4)‐β‐D ‐galactopyranoside ( 2 ), and (2α,3β,5α,14β,22R,25R)‐26‐(β‐D ‐glucopyranosyloxy)‐2,22‐dihydroxyfurostan‐3‐yl β‐D ‐glucopyranosyl‐(1→2)‐[β‐D ‐glucopyranosyl‐(1→3)]‐β‐D ‐galactopyranoside ( 3 ).  相似文献   

2.
A new furostanol saponin, sisalasaponin C ( 1 ), and a new spirostanol saponin, sisalasaponin D ( 2 ), were isolated from the fresh leaves of Agave sisalana, along with three other known steroidal saponins and two stilbenes. Their structures were identified as (3β,5α,6α,22α,25R)‐3,26‐bis[(β‐D ‐glucopyrano‐ syl)oxy]‐22‐hydroxyfurostan‐6‐yl β‐D ‐glucopyranoside ( 1 ), (3β,5α,25R)‐12‐oxospirostan‐3‐yl 6‐deoxy‐α‐L ‐mannopyranosyl‐(1→4)‐β‐D ‐glucopyranosyl‐(1→3)‐[β‐D ‐xylopyranosyl‐(1→3)‐β‐D ‐glucopyranosyl‐(1→2)]‐β‐D ‐glucopyranosyl‐(1→4)‐β‐D ‐galactopyranoside ( 2 ), (3β,5α,6α,22α,25R)‐22‐methoxyfurostane‐3,6,26‐triyl tris‐β‐D ‐glucopyranoside, cantalasaponin‐1, polianthoside D, (E)‐ and (Z)‐2,3,4′,5‐tetrahydroxystilbene 2‐O‐β‐D ‐glucopyranosides. The last three known compounds were isolated from the fresh leaves of Agavaceae for the first time. The structures of the new compounds were elucidated by detailed spectroscopic analysis, including 1D‐ and 2D‐NMR experiments, and chemical techniques.  相似文献   

3.
A new sterol, 5α,6α‐epoxy‐3β‐hydroxy‐(22E,24R)‐ergosta‐8,22‐dien‐7‐one ( 1 ), together with eight known sterols, 5α,6α‐epoxy‐(22E,24R)‐ergosta‐8,22‐diene‐3β,7α‐diol ( 2 ), 5α,6α‐epoxy‐(22E,24R)‐ergosta‐8,22‐diene‐3β,7β‐diol ( 3 ), 5α,6α‐epoxy‐(22E,24R)‐ergosta‐8(14),22‐diene‐3β,7α‐diol ( 4 ), 3β‐hydroxy‐(22E,24R)‐ergosta‐5,8,22‐trien‐7‐one ( 5 ), ergosterol peroxide ( 6 ), clerosterol ( 7 ), decortinol ( 8 ), and decortinone ( 9 ), were isolated from the stems of Momordica charantia. Their structures were elucidated by mean of extensive spectroscopic methods, including 1H, 13C, 2D‐NMR and HR‐EI‐MS, as well as comparison with the literature data. Compounds 1 , 4 , 5 , 8 , and 91 were not cytotoxic against the SK‐Hep 1 cell line.  相似文献   

4.
Five new steroidal glycosides were isolated from the roots of Balanites aegyptiaca, a widely used African medicinal plant. On the basis of spectroscopic and chemical evidence, their structures were determined as (3β,12α,14β,16β)‐12‐hydroxycholest‐5‐ene‐3,16‐diyl bis(β‐D ‐glucopyranoside) ( 1 ), (3β,20S,22R,25R)‐ and (3β,20S,22R,25S)‐26‐(β‐D ‐glucopyranosyloxy)‐22‐methoxyfurost‐5‐en‐3‐yl β‐D ‐xylopyranosyl‐(1→3)‐β‐D ‐glucopyranosyl‐(1→4)[α‐L ‐rhamnopyranosyl‐(1→2)]‐β‐D ‐glucopyranoside ( 2 and 3 , resp.), and (3β,20S,22R,25R)‐ and (3β,20S,22R,25S)‐spirost‐5‐en‐3‐yl β‐D ‐xylopyranosyl‐(1→3)‐β‐D ‐glucopyranosyl‐(1→4)[α‐L ‐rhamnopyranosyl‐(1→2)]‐β‐D ‐glucopyranoside ( 4 and 5 , resp.)  相似文献   

5.
Two new monodesmosidic cycloartane triterpene glycosides, depressosides E and F, and two new flavonol glycosides, depressonol A and B, were isolated from the butanol‐soluble part of the EtOH extract of Corchorus depressus L . The structures of the new compounds were elucidated as (22R,24S)‐22,25‐epoxy‐9,19‐cyclolanostane‐3β,16β,24‐triol 3‐[α‐L ‐rhamnopyranosyl‐(1→4)‐β‐D ‐glucopyranoside] ( 1 ), (22R,24S)‐22,25‐epoxy‐9,19‐cyclolanostane‐3β,16β,24‐triol 3‐[α‐D ‐glucopyranosyl‐(1→3)‐β‐D ‐glucopyranoside] ( 2 ), kaempferol 3‐[β‐D ‐glucopyranosyl‐(1→4)‐β‐D ‐galactopyranoside] 7‐[α‐L ‐arabinofuranoside] ( 4 ), and kaempferol 3‐[β‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐galactopyranoside] 7‐[α‐L ‐arabinofuranoside] ( 5 ) on the basis of chemical evidence and detailed spectroscopic studies.  相似文献   

6.
Four new furostanol steroid saponins, borivilianosides A–D ( 1 – 4 , resp.), corresponding to (3β,5α,22R,25R)‐26‐(β‐D ‐glucopyranosyloxy)‐22‐hydroxyfurostan‐3‐yl Oβ‐D ‐xylopyranosyl‐(1→3)‐Oβ‐D ‐glucopyranosyl‐(1→4)‐O‐[α‐L ‐rhamnopyranosyl‐(1→2)]‐β‐D ‐galactopyranoside ( 1 ), (3β,5α,22R,25R)‐ 26‐(β‐D ‐glucopyranosyloxy)‐22‐methoxyfurostan‐3‐yl Oβ‐D ‐xylopyranosyl‐(1→3)‐Oβ‐D ‐glucopyranosyl‐(1→4)‐O‐[α‐L ‐rhamnopyranosyl‐(1→2)]‐β‐D ‐galactopyranoside ( 2 ), (3β,5α,22R,25R)‐26‐(β‐D ‐glucopyranosyloxy)‐22‐methoxyfurostan‐3‐yl Oβ‐D ‐xylopyranosyl‐(1→3)‐O‐[β‐D ‐glucopyranosyl‐(1→2)]‐Oβ‐D ‐glucopyranosyl‐(1→4)‐β‐D ‐galactopyranoside ( 3 ), and (3β,5α,25R)‐26‐(β‐D ‐glucopyranosyloxy)furost‐20(22)‐en‐3‐yl Oβ‐D ‐xylopyranosyl‐(1→3)‐O‐[β‐D ‐glucopyranosyl‐(1→2)]‐Oβ‐D ‐glucopyranosyl‐(1→4)‐β‐D ‐galactopyranoside ( 4 ), together with the known tribuluside A and (3β,5α,22R,25R)‐26‐(β‐D ‐glucopyranosyloxy)‐22‐methoxyfurostan‐3‐yl Oβ‐D ‐xylopyranosyl‐(1→2)‐O‐[β‐D ‐xylopyranosyl‐(1→3)]‐Oβ‐D ‐glucopyranosyl‐(1→4)‐O‐[α‐L ‐rhamnopyranosyl‐(1→2)]‐β‐D ‐galactopyranoside were isolated from the dried roots of Chlorophytum borivilianum Sant and Fern . Their structures were elucidated by 2D ‐NMR analyses (COSY, TOCSY, NOESY, HSQC, and HMBC) and mass spectrometry.  相似文献   

7.
Four new tirucallane triterpenoid saponins, named munronosides I–IV ( 2 – 5 ), along with three known triterpenoids, sapelin B ( 1 ), melianodiol, and (3β)‐22,23‐epoxytirucall‐7‐ene‐3,24,25‐triol, were isolated from the EtOH extract of the whole plants of Munronia delavayi Franch by chromatographic methods. On the basis of spectroscopic evidences, the structures of 2 – 5 were elucidated as (20S,23R,24S)‐21,25‐epoxy‐29‐{{Oβ‐d‐ glucopyranosyl‐(1→3)‐O‐[α‐l‐ rhamnopyranosyl‐(1→6)]‐β‐d‐ glucopyranosyl}oxy}‐23,24‐dihydroxytirucall‐7‐ene‐3,21‐dione ( 2 ), (3β,20S,23R,24S)‐21,25‐epoxy‐29‐{{Oβ‐d‐ glucopyranosyl‐(1→3)‐O‐[α‐l‐ rhamnopyranosyl‐(1→6)]‐β‐d‐ glucopyranosyl}oxy}‐3,23,24‐trihydroxytirucall‐7‐en‐21‐one ( 3 ), (20S,23R,24S)‐24‐(acetyloxy)‐21,25‐epoxy‐29‐{{Oβ‐d‐ glucopyranosyl‐(1→3)‐O‐[α‐l‐ rhamnopyranosyl‐(1→6)]‐β‐d‐ glucopyranosyl}oxy}‐23‐hydroxytirucall‐7‐ene‐3,21‐dione ( 4 ), and (3β,20S,23R,24S)‐24‐(acetyloxy)‐21,25‐epoxy‐29‐{{Oβ‐d‐ glucopyranosyl‐(1→3)‐O‐[α‐l‐ rhamnopyranosyl‐(1→6)]‐β‐d‐ glucopyranosyl}oxy}‐3,23‐dihydroxytirucall‐7‐en‐21‐one ( 5 ).  相似文献   

8.
Three new withanolide compounds, named baimantuoluolines D–F, along with three known withanolides and a lignan were isolated from the flower of Datura metel L., the parts effective against psoriasis. The structures of the new compounds were elucidated as (5α,6β,12β,20R,22R,24R,25S)‐21,24‐epoxy‐5,6,12‐trihydroxy‐27‐methoxy‐1‐oxowith‐2‐enolide ( 1 ), (5α,6β,12β,20R,22R,24R,25S)‐21,24‐epoxy‐5,6,12,27‐tetrahydroxy‐1‐oxowith‐2‐enolide ( 2 ), and (5α,6β,12β,22R)‐5,6,12,21‐tetrahydroxy‐1‐oxowith‐24‐enolide( 3 ) on the basis of physicochemical evidence.  相似文献   

9.
Four new steroidal saponins, named disporosides A–D ( 1 – 4 ), corresponding to (3β,25R)‐3‐[(β‐D ‐glucopyranosyl‐(1→2)‐[β‐D ‐glucopyranosyl‐(1→6)]‐β‐D ‐glucopyranosyl)oxy]‐5β‐spirostan ( 1 ), (3β,25R)‐3‐[(β‐D ‐glucopyranosyl‐(1→2)‐[6‐O‐hexadecanoyl‐β‐D ‐glucopyranosyl‐(1→6)]‐β‐D ‐glucopyranosyl)oxy]‐5β‐spirostan ( 2 ), (3β,22R,25R)‐26‐[(β‐D ‐glucopyranosyl)oxy]‐3‐[(β‐D ‐glucopyranosyl‐(1→2)‐β‐D ‐glucopyranosyl)oxy]‐5β‐furostan ( 3 ), and (3β,22R,25R)‐26‐[(β‐D ‐glucopyranosyl)oxy]‐3‐[(β‐D ‐glucopyranosyl‐(1→2)‐[β‐D ‐glucopyranosyl‐(1→6)]‐β‐D ‐glucopyranosyl)oxy]‐5β‐furostan ( 4 ), have been isolated from the fresh rhizomes of Disporopsis pernyi, together with the three known compounds Ys‐I, agavoside B, and (3β,25R)‐3‐[(β‐D ‐xylopyranosyl‐(1→3)‐β‐D ‐glucopyranosyl‐(1→4)‐β‐D ‐galactopyranosyl)oxy]‐5α‐spirostan‐12‐one. Their structures were elucidated by spectroscopic analyses, chemical transformations (acid hydrolysis), and comparison with literature data.  相似文献   

10.
Three new and one known ecdysteroids were identified in the MeOH extract of the roots of Serratula wolffii. The new compounds isolated were (11α)‐11‐hydroxyshidasterone ( 1 ), (2β,3α,5β,14β,22R)‐2,3,20,22,25‐pentahydroxycholest‐7‐en‐6‐one ( 2 ), and (2β,3α,5β,22R)‐2,3,20,22,25‐pentahydroxycholest‐7‐en‐6‐one ( 3 ), together with the known ponasterone A ( 4 ). This latter compound was now better characterized than earlier. The structures of compounds 1 – 4 were established by extensive spectroscopic techniques, including one‐ and two‐dimensional NMR methods.  相似文献   

11.
Two novel echinocystic acid (=(3β,16α)‐3,16‐dihydroxyolean‐12‐en‐28‐oic acid) glycosides, foetidissimosides C ( 1 ), and D ( 2 ), along with new cucurbitane glycosides, i.e., foetidissimosides E/F ( 3 / 4 ) as an 1 : 1 mixture of the (24R)/(24S) epimers, were obtained from the roots of Cucurbita foetidissima. Their structures were elucidated by means of a combination of homo‐ and heteronuclear 2D‐NMR techniques (COSY, TOCSY, NOESY, ROESY, HSQC, and HMBC), and by FAB‐MS. The new compounds were characterized as (3β,16α)‐28‐{[Oβ‐D ‐glucopyranosyl‐(1→3)‐Oβ‐D ‐xylopyranosyl‐(1→4)‐O‐6‐deoxy‐α‐L ‐mannopyranosyl‐(1→2)‐α‐L ‐arabinopyranosyl]oxy}‐16‐hydroxy‐28‐oxoolean ‐12‐en‐3‐yl β‐D ‐glucopyranosiduronic acid ( 1 ), (3β,16α)‐16‐hydroxy‐28‐oxo‐28‐{{Oβ‐D ‐xylopyranosyl‐(1→3)‐O‐[β‐D ‐xylopyranosyl‐(1→4)]‐O‐6‐deoxy‐α‐L ‐mannopyranosyl‐(1→2)‐α‐L ‐arabinopyranosyl}oxy}olean‐12‐en‐3‐yl β‐D ‐glucopyranosiduronic acid ( 2 ), and (3β,9β,10α,11α,24R)‐ and (3β,9β,10α,11α,24S)‐25‐(β‐D ‐glucopyranosyloxy)‐9‐methyl‐19‐norlanost‐5‐en‐3‐yl 2‐Oβ‐D ‐glucopyranosyl‐β‐D ‐glucopyranoside ( 3 and 4 , resp.).  相似文献   

12.
A minor, unprecedented diterpene, 3β,17‐dihydroxycleistantha‐12,15‐dien‐2‐one ( 1 ), was isolated from the CHCl3‐soluble part of the EtOH extract of the pericarp of Trewia nudiflora. The structure of 1 was elucidated by means of 1D‐ and 2D‐NMR spectroscopic analyses as well as by HR‐MS. Also isolated were two known triterpenes, glutin‐5‐en‐3‐ol and olean‐18‐en‐3‐one (germanicone), as well as three known sterols, (22E,24R)‐5α,8α‐epidioxyergosta‐6,22‐dien‐3β‐ol, (22E,24R)‐5α,8α‐epidioxyergosta‐6,9(11),22‐trien‐3β‐ol, and (22E,24R)‐6‐methoxyergosta‐7,22‐dien‐3,5‐diol.  相似文献   

13.
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   

14.
Three new withanolide compounds named baimantuoluoline A ( 1 ), B ( 2 ), and C ( 3 ) and the two known withanolides withafastuosin E ( 4 ) and withametelin C ( 5 ) were isolated from the fraction exhibiting activity for psoriasis in the flower of Datura metel L. The three new structures were determined as (5α,6α,7α,12β,15β,22R)‐6,7‐epoxy‐5,12,15‐trihydroxy‐1‐oxowitha‐2,24‐dienolide ( 1 ), (5α,6β,15β,22R)‐ 5,6,15,21‐tetrahydroxy‐1‐oxowith‐24‐enolide ( 2 ), and (5α,6β,12β,22R)‐5,6,12,21‐tetrahydroxy‐27‐methoxy‐1‐oxowitha‐2,24‐dienolide ( 3 ) on the basis of extensive spectroscopic data (HR‐ESI‐MS, 1H‐ and 13C‐NMR, 1H,1H‐COSY, HSQC, HMBC, and NOESY) (withanolide=22‐hydroxyergostan‐26‐oic acid δ‐lactone).  相似文献   

15.
Molecular diversity was generated by hydrolyzing the crude root saponins of Panax notoginseng (Burk .) F. H. Chen under mild acidic condition (AcOH/EtOH 1 : 1). From the acid hydrolysate, five new dammarane glycosides, named notoginsenoside T1 (=(3β,6α,12β,20E,23RS)‐24,25‐epoxy‐6‐[(β‐D ‐glucopyranosyl)oxy]‐dammar‐20(22)‐ene‐3,12,23‐triol; 1 ), notoginsenoside T2 (=(3β,6α,12β,20E,23RS)‐24,25‐epoxy‐6‐[(β‐D ‐glucopyranosyl)oxy]‐23‐methoxydammar‐20(22)‐ene‐3,12‐diol; 2 ), notoginsenoside T3 (=(3β,6α,12β,20S)‐6‐[(β‐D ‐glucopyranosyl)oxy]‐20‐ethoxydammar‐24‐ene‐3,12‐diol; 3 ), notoginsenoside T4 (=(3β,6α,12β,20S,22E,24RS)‐6‐[(β‐D ‐glucopyranosyl)oxy]dammar‐22‐ene‐3,12,20,24,25‐pentol; 4 ), and notoginsenoside T5 (=(3β,6α,12β, 24E)‐6‐[(β‐D ‐xylopyranosyl‐(1→2)‐β‐D ‐glucopyranosyl)oxy]dammara‐20(21),24‐diene‐3,12‐diol; 5 ), were isolated, together with 15 known dammarane glycosides, and their structures were elucidated on the basis of spectroscopic evidence. Among the known compounds, ginsenosides Rg3 and Rh1 were isolated as major constituents, in addition to ginsenosides Rg5, Rh4, and a mixture of (20R)‐ and (20S)‐25‐hydroxyginsenoside Rh1, all of which were obtained from P. notoginseng for the first time.  相似文献   

16.
Nine compounds were isolated from Nocardia sp. YIM 64630, and their structures were elucidated as 5′-O-acetyl-2′-deoxyuridine (1), 22E,24R-5α,6α-epoxyergosta-8(14),22-diene-3β,7α-diol (2), 22E,24R-5α,6α-epoxyergosta-8,22-diene-3β,7α-diol (3), 22E,24R-ergosta-7,22-diene-3β,5α,6β-triol (4), 5α,8α-epidioxyergosta-6,22-dien-3β-ol (5), 4′,5,6-trihydroxy-7-methoxyisoflavone (6), 2,4,4′-trihydroxy-deoxybenzoin (7), methyl [4-hydroxyphenyl]acetate (8) and daidzein by extensive spectroscopic analyses. Compound 1 was isolated from natural resources for the first time. The antimicrobial and antioxidant activities of compounds 18 were investigated.  相似文献   

17.
Six new triterpenoid glycosides, gynosaponins I–VI ( 1 – 6 , resp.), together with three known compounds, ginseng Rb1 ( 7 ), gypenoside XLIX ( 8 ), and gylongiposide I ( 9 ), were isolated from the aerial parts of Gynostemma pentaphyllum. Based on ESI‐MS, IR, 1D‐ and 2D‐NMR data (HMQC, HMBC, COSY, and TOCSY), the structures of the new compounds were determined as (3β,12β,20S)‐trihydroxydammar‐24‐ene 20‐O‐[α‐rhamnopyranosyl‐(1→2)]‐β‐glucopyranoside ( 1 ), (3β,12β,20S)‐trihydroxydammar‐24‐ene 20‐O‐[α‐rhamnopyranosyl‐(1→2)] [α‐rhamnopyranosyl‐(1→3)]‐β‐glucopyranoside ( 2 ), (3β,12β,20S)‐trihydroxydammar‐24‐ene 3‐Oβ‐glucopyranosyl‐20‐O‐[α‐rhamnopyranosyl‐(1→2)]‐β‐glucopyranoside ( 3 ), (3β,12β,20S)‐trihydroxydammar‐24‐ene 3‐Oβ‐glucopyranosyl‐20‐O‐[α‐rhamnopyranosyl‐(1→2)] [α‐rhamnopyranosyl‐(1→3)]‐β‐glucopyranoside ( 4 ), (3β,12β,20S)‐trihydroxydammar‐24‐ene 3‐O‐{[β‐glucopyranosyl‐(1→2)]‐β‐glucopyranosyl}‐20‐O‐[α‐rhamnopyranosyl‐(1→2)]‐β‐glucopyranoside ( 5 ), and (3β,12β,20S)‐trihydroxydammar‐24‐ene 3‐O‐{[β‐glucopyranosyl‐(1→2)]‐β‐glucopyranosyl}‐20‐O‐[α‐rhamnopyranosyl‐(1→2)] [α‐rhamnopyranosyl‐(1→3)]‐β‐glucopyranoside ( 6 ).  相似文献   

18.
Chemical examination of a marine sponge Xestospongia sp. resulted in the isolation of 20 sterol derivatives ( 1 – 20 ), including eight new sterols namely aragusterols J – L ( 1 – 3 ), (5α,7α,12β,22E)‐7,12,18‐trihydroxystigmast‐22‐en‐3‐one ( 4 ), (5α,7α,12β,24R)‐ and (5α,7α,12β,24S)‐7,12,20‐trihydroxystigmastan‐3‐one ( 5 / 6 ), and (5α,7α,12β,22E,24R)‐ and (5α,7α,12β,22E,24S)‐7,12,20‐trihydroxyergost‐22‐en‐3‐one ( 7 / 8 ). The structures of new compounds were determined through extensive spectroscopic analyses and chemical conversion. The sterol diversity was mainly characterized by the presence of a cyclopropane unit at side chain, while compound 4 with 18‐hydroxymethyl group was found in stigmasterol family for the first time. Cytotoxic test revealed the inhibitory effects of compounds 1 , 4 , and 17 against human leukemia cell line K562 with IC50 values of 18.3, 24.1, and 34.3 μm , respectively.  相似文献   

19.
In search for bioactive compounds from the flower of Datura metel L., three new withanolide glucosides, namely baimantuoluosides A, B, and C ( 1 – 3 , resp.) were isolated. Enzymatic hydrolysis of 1 – 3 afforded the corresponding aglycones 1a, 2a , and 3a , respectively. The structures of the new compounds were elucidated as (5α,6α,7α,12β,22R)‐5,12‐dihydroxy‐1,26‐dioxo‐6,7 : 22,26‐diepoxyergosta‐2,24‐dien‐27‐yl β‐D ‐glucopyranoside ( 1 ), (5α,6α,7α,12α,22R)‐5,12‐dihydroxy‐1,26‐dioxo‐6,7 : 22,26‐diepoxyergosta‐2,24‐dien‐27‐yl β‐D ‐glucopyranoside ( 2 ), (5α,6α,7α,22R)‐5‐hydroxy‐1,26‐dioxo‐6,7 : 22,26‐diepoxyergosta‐2,24‐dien‐27‐yl β‐D ‐glucopyranoside ( 3 ) on the basis of chemical and physicochemical evidence, and are further confirmed by the structure determination by X‐ray diffraction of withanolide aglycone 1a .  相似文献   

20.
Phytochemical analyses were carried out on the rhizomes of Clintonia udensis (Liliaceae) with particular attention paid to the steroidal glycoside constituents, resulting in the isolation of three new polyhydroxylated spirostanol glycosides, named clintonioside A ( 1 ), B ( 2 ), and C ( 3 ). On the basis of their spectroscopic data, including 2D‐NMR spectroscopy, in combination with acetylation and hydrolytic cleavage, the structures of 1 – 3 were determined to be (1β,3β,23S,24S,25R)‐1,23,24‐trihydroxyspirost‐5‐en‐3‐yl Oβ‐D ‐glucopyranosyl‐(1→4)‐O‐[α‐L ‐rhamnopyranosyl‐(1→2)]‐β‐D ‐glucopyranoside ( 1 ), (1β,3β,23S,24S)‐3,21,23,24‐tetrahydroxyspirosta‐5,25(27)‐dien‐1‐yl Oα‐L ‐rhamnopyranosyl‐(1→2)‐O‐[β‐D ‐xylopyranosyl‐(1→3)]‐β‐D ‐glucopyranoside ( 2 ), and (1β,3β,23S,24S)‐21‐(acetyloxy)‐24‐[(6‐deoxy‐β‐D ‐gulopyranosyl)oxy]‐3,23‐dihydroxyspirosta‐5,25(27)‐dien‐1‐yl Oα‐L ‐rhamnopyranosyl‐(1→2)‐O‐[β‐D ‐xylopyranosyl‐(1→3)]‐β‐D ‐glucopyranoside ( 3 ).  相似文献   

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