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1.
Three new glycosides, (3β,5α,8α,11α,12β,14β,17α,20R)‐3‐[(2,6‐dideoxy‐4‐O‐(6‐deoxy‐3‐O‐methyl‐β‐D ‐allopyranosyl)‐3‐O‐methyl‐β‐D ‐arabino‐hexopyranosyl)oxy]‐12‐O‐tigloyl‐8,20 : 11,20‐diepoxypregnane‐12,14‐diol ( 1 ), (3β,5α,8α,11α,12β,14β,17α,20R)‐3‐[(2,6‐dideoxy‐4‐O‐(6‐deoxy‐3‐O‐methyl‐β‐D ‐ allopyranosyl)‐3‐O‐methyl‐β‐D ‐arabino‐hexopyranosyl)oxy]‐12‐O‐(2‐methylbutanoyl)‐8,20 : 11,20‐diepoxypregnane‐12,14‐diol ( 2 ), and (3β,5α,11α,12β,14β,17α)‐12‐acetoxy‐3‐[(2,6‐dideoxy‐4‐O‐(6‐deoxy‐3‐O‐methyl‐β‐D ‐allopyranosyl)‐3‐O‐methyl‐β‐D ‐arabino‐hexopyranosyl)oxy]‐20‐oxo‐8,14‐epoxypregnan‐ 11‐yl isobutyrate ( 3 ) were isolated from the stems of Marsdenia tenacissima. The structures of the new compounds were elucidated by means of spectral data, including HR‐ESI‐MS, and 1D‐ and 2D‐NMR.  相似文献   

2.
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   

3.
建立了逐步合成具有重要生物活性的2-脱氧-2-氨基葡萄糖寡糖链的通用方法。采用邻苯二甲酰基保护氨基、硫代苯基为还原末端的离去基团,以氨基葡萄糖为起始原料,几种保护的几丁寡糖及结构类似物被合成:3-O-乙酰基-4,6-O-亚苄基-2-脱氧-2-邻苯二甲酰亚氨基-b-D-吡喃葡萄糖-(1→4)-(3-O-乙酰基-6-O-苄基-2-脱氧-2-邻苯二甲酰亚氨基)-b-D-吡喃葡萄糖甲苷(4)、3-O-乙酰基-4,6-O-亚苄基-2-脱氧-2-邻苯二甲酰亚氨基-b-D-吡喃葡萄糖-(1→4)-(3-O-乙酰基-6-O-苄基-2-脱氧-2-邻苯二甲酰亚氨基-b-D-吡喃葡萄糖)-(1→4)-(3-O-乙酰基-6-O-苄基-2-脱氧-2-邻苯二甲酰亚氨基)-b-D-吡喃葡萄糖甲苷(6)、3-O-乙酰基-4,6-O-亚苄基-2-脱氧-2-邻苯二甲酰亚氨基-b-D-吡喃葡萄糖-(1→3)-(4,6-O-亚苄基-2-脱氧-2-邻苯二甲酰亚氨基)-b-D-吡喃葡萄糖甲苷(8)、3-O-乙酰基-4,6-O-亚苄基-2-脱氧-2-邻苯二甲酰亚氨基-b-D-吡喃葡萄糖-(1→3)-(4,6-O-亚苄基-2-脱氧-2-邻苯二甲酰亚氨基-b-D-吡喃葡萄糖)- (1→3)-(4,6-O-亚苄基-2-脱氧-2-邻苯二甲酰亚氨基)- b-D-吡喃葡萄糖甲苷(10)。所合成化合物通过核磁共振和质谱分析确证了其化学结构。  相似文献   

4.
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   

5.
The hydrolysis reactions of N-(O,O'diisopropyl)phosphoryl-L-α-alanine (DIPP-L-α-Ala), N-(O,O'diisopropyl)- phosphoryl-D-α-alanine (DIPP-D-α-Ala), N-(O,O'-diisopropyl)phosphoryl-β-alanine (DIPP-β-Ala) and N-(O,O'-diisopropyl)phosphoryl-γ-amino butyric acid (DIPP-γ-Aba), were studied by HPLC and their hydrolysis reaction kinetic equations were obtained. Under acid conditions, the reaction rate of DIPP-L-α-Ala was close to that of DIPP-D-α-Ala and the same rule was true between DIPP-β-Ala and DIPP-γ-Aba. Meantime, the reaction rate of DIPP-L/D-α-Ala was as 10 times as that of DIPP-β-Ala or DIPP-γ-Aba. Under basic conditions, the hydrolysis reactions of DIPP-β-Ala and DIPP-γ-Aba almost did not take place and the reaction rate of DIPP-L/D-α-Ala was about 1/10 of that under acid conditions. Moreover, theoretical calculation further illuminated the differences of the hydrolysis rate from the view of energy. The results would provide some helpful clues to why nature chose a-amino acids but not other kinds of analogs as protein backbones.  相似文献   

6.
The new rearranged‐abietane diterpene 1 , the four new triterpenoids 2 – 5 , and the new aminoethylphenyl oligoglycoside 6 , besides 19 known compounds, were isolated from the roots of Schnabelia tetradonta, a Chinese endemic herb. The structures of the new compounds were elucidated on the basis of spectroscopic evidence as 12,17‐epoxy‐11,14,16‐trihydroxy‐17(15→16)‐abeo‐abieta‐8,11,13,15‐tetraen‐7‐one ( 1 ), 21β‐(β‐D ‐glucopyranosyloxy)‐2α,3α‐dihydroxyolean‐12‐en‐28‐oic acid ( 2 ), 2β,3β,16β‐trihydroxy‐15‐oxo‐28‐norolean‐12‐en‐23‐oic acid ( 3 ), 3β‐[(4‐O‐acetyl‐β‐D ‐glucopyranuronosyl)oxy]‐2β,16β‐dihydroxy‐28‐norolean‐15‐oxo‐12‐en‐23‐oic acid ( 4 ), 3β‐[(4‐O‐acetyl‐6‐O‐methyl‐β‐D ‐glucopyranuronosyl)oxy]‐2β,16β‐dihydroxy‐15‐oxo‐28‐norolean‐12‐en‐23‐oic acid ( 5 ), and 4‐[2‐(acetylamino)ethyl]phenyl O‐6‐O‐[(Z)‐p‐methoxycinnamoyl]‐β‐D ‐glucopyranosyl‐(1→2)]‐O‐[β‐D ‐glucopyranosyl‐(1→3)]‐4‐O‐acetyl‐α‐L ‐rhamnopyranoside ( 6 ), respectively.  相似文献   

7.
Obesity is a complex health issue and it can cause many health and social problems. Previous studies reported that lipase is a main target for obesity treatment. We synthesized Rexo‐2‐norbornyl‐Nn‐butylcarbamate and Sexo‐2‐norbornyl‐Nn‐butylcarbamate as potential pseudomonas lipase inhibitors to probe the enantioselectivity of the enzyme and demonstrated that Rexo‐2‐norbornyl‐Nn‐butylcarbamate had better enzyme enantioselectivity, ki and the docking model with Pseudomonas species lipase in our previous studies. In this article, we reported the property of the Pseudomonas species lipase inhibitors, R‐and Sendo‐2‐norbornyl‐Nn‐butylcarbamate and compared the docking models of these two compounds with R‐ and Sexo‐2‐norbornyl‐Nn‐butylcarbamates by AutoDock. We found that Sendo‐2‐norbornyl‐Nn‐butylcarbamate has the best enantioselectivity, ki and docking model and this study could provide useful information about enzyme enantioselectivity for the development of Pseudomonas species lipase inhibitors for obesity treatment.  相似文献   

8.
Eight new acylated preatroxigenin saponins 1 – 8 were isolated as four inseparable mixtures of the trans‐ and cis‐4‐methoxycinnamoyl derivatives, atroximasaponins A1/A2 ( 1 / 2 ), B1/B2 ( 3 / 4 ), C1/C2 ( 5 / 6 ) and D1/D2 ( 7 / 8 ) from the roots of Atroxima congolana. These compounds are the first examples of triterpene saponins containing preatroxigenin (=(2β,3β,4α,22β)‐2,3,22,27‐tetrahydroxyolean‐12‐ene‐23,28‐dioic acid as aglycone. Their structures were elucidated on the basis of extensive 1D‐ and 2D‐NMR studies and FAB‐MS as 3‐O(β‐D ‐glucopyranosyl)preatroxigenin 28‐{Oβ‐D ‐xylopyranosyl‐(1→4)‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐O‐[Oβ‐D ‐glucopyranosyl‐(1→3)‐β‐D ‐glucopyranosyl‐(1→3)]‐4‐O‐(trans‐4‐methoxycinnamoyl)‐β‐D ‐fucopyranoyl} ester ( 1 ) and its cis‐isomer 2 , 3‐O‐(β‐D ‐glucopyranosyl)preatroxigenin 28‐{Oβ‐D ‐xylopyranosyl‐(1→4)‐Oα‐L ‐rhamnopyranosyl‐(1→ 2)‐O‐[O‐6‐O‐acetyl‐β‐D ‐glucopyranosyl‐(1→3)‐β‐D ‐glucopyranosyl‐(1→3)]‐4‐O‐(trans‐ 4‐methoxycinnamoyl)‐β‐D ‐fucopyranosyl} ester ( 3 ) and its cis‐isomer 4 , 3‐O‐(β‐D ‐glucopyranosyl)preatroxigenin 28‐{Oβ‐D ‐xylopyranosyl‐(1→4)‐O‐[β‐D ‐apiofuranosyl‐(1→3)]‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐O‐[O‐6‐ O‐acetyl‐β‐D ‐glucopyranosyl‐(1→3)‐β‐D ‐glucopyranosyl‐(1→3)]‐4‐O‐(trans‐4‐methoxycinnamoyl)‐β‐D ‐fucopyranoyl} ester ( 5 ) and its cis‐isomer 6 , 3‐O‐(β‐D ‐glucopyranosyl)preatroxigenin 28‐{Oβ‐D ‐xylopyranosyl‐(1→4)‐O‐[β‐D ‐apiofuranosyl‐(1→3)]‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐O‐[Oβ‐D ‐xylopyranosyl‐(1→3)‐β‐D ‐glucopyranosyl‐(1→3)]‐4‐O‐(trans‐4‐methoxycinnamoyl)‐β‐D ‐fucopyranosyl ester ( 7 ) and its cis‐isomer 8 .  相似文献   

9.
A simple and highly efficient stereoselective total synthesis of the 6‐alkylated pyranones (6R)‐6‐[(1E,4R,6R)‐4,6‐dihydroxy‐10‐phenyldec‐1‐en‐1‐yl]‐5,6‐dihydro‐2H‐pyran‐2‐one ( 1 ) and (6S)‐5,6‐dihydro‐6‐[(2R)‐2‐hydroxy‐6‐phenylhexyl]‐2H‐pyran‐2‐one ( 2 ) was developed using Crimmins' aldol reaction, SmI2 reduction, GrubbsII‐catalyzed olefin cross‐metathesis, and Still's modified Horner? Wadsworth? Emmons reaction.  相似文献   

10.
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   

11.
Two new C-21 steroidal glycosides, mucronatosides M(1) and N(2), were isolated from the stems of Stephanotis mucronata, together with one known compound stephanoside M(3). On the basis of chemical evidence and extensive spectroscopic methods, including one-dimensional and two-dimensional NMR, the structures of the two new compounds were identified as 12-O-tigloyl-20-O-N-methylanthraniloyl sarcoslin 3-O-β-D-glucopyranosyl-(1→4)-6- deoxy-3-O-methyl-β-D-allopyranosyl-(→4)-β-D-cymaropyranosyl-(1→4)-β-D-cymaropyranoside (1), and 12-O- cinnamoyl-20-O-nicotinoyl( 2OS)-pregn-6-ene-3 β,5α,8βm12 β,14β,17β,20-heptanol 3-O-β-D-glucopyranosyl-(1→4)-6- deoxy-3-O-methyl-β-D-allopyranosyl-(1→4)-β-D-cymaropyranosyl-(1→4)-β-D-cymaropyranoside (2).  相似文献   

12.
Four new triterpenoidal saponins acylated with monoterpenic acid, i.e., adianthifoliosides C, D, E, and F ( 1 – 4 ), besides the two known julibroside III and the monodesmonoterpenyl elliptoside A, were isolated from the roots of Albizia adianthifolia. Their structures were elucidated on the basis of extensive 1D‐ and 2D‐NMR studies and mass spectrometry as 3‐O‐{Oα‐L ‐arabinopyranosyl‐(1→2)‐Oβ‐d‐ fucopyranosyl‐(1→6)‐O‐[β‐d‐ glucopyranosyl‐(1→2)]‐β‐d‐ glucopyranosyl}‐21‐O‐{(2E,6S)‐6‐{{4‐O‐[(2E,6S)‐2,6‐dimethyl‐6‐(β‐D ‐quinovopyranosyloxy)octa‐2,7‐dienoyl]‐β‐d‐ quinovopyranosyl}oxy}‐2‐(hydroxymethyl)‐6‐methylocta‐2,7‐dienoyl}acacic acid 28‐{Oα‐L ‐arabinofuranosyl‐(1→4)‐O‐[β‐d‐ glucopyranosyl‐(1→3)]‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐β‐d‐ glucopyranosyl} ester ( 1 ), 21‐O‐{(2E,6S)‐6‐{{4‐O‐[(2E,6S)‐2,6‐dimethyl‐6‐(β‐d‐ quinovopyranosyloxy)octa‐2,7‐dienoyl]‐β‐d‐ quinovopyranosyl}oxy}‐2‐(hydroxymethyl)‐6‐methylocta‐2,7‐dienoyl}‐3‐O‐{Oβ‐D ‐xylopyranosyl‐(1→2)‐Oβ‐d‐ fucopyranosyl‐(1→6)‐2‐(acetylamino)‐2‐deoxy‐β‐d‐ glucopyranosyl}acacic acid 28‐{Oα‐L ‐arabinofuranosyl‐(1→4)‐O‐[β‐d‐ glucopyranosyl‐(1→3)]‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐β‐d‐ glucopyranosyl} ester ( 2 ), 21‐O‐{(2E,6S)‐6‐{{3‐O‐[(2E,6S)‐2,6‐dimethyl‐6‐(β‐d‐ quinovopyranosyloxy)octa‐2,7‐dienoyl]‐β‐d‐ quinovopyranosyl}oxy}‐2,6‐dimethylocta‐2,7‐dienoyl}‐3‐O‐{Oβ‐D ‐xylopyranosyl‐(1→2)‐Oβ‐d‐ fucopyranosyl‐(1→6)‐2‐(acetylamino)‐2‐deoxy‐β‐d‐ glucopyranosyl}acacic acid 28‐{Oα‐L ‐arabinofuranosyl‐(1→4)‐O‐[β‐d‐ glucopyranosyl‐(1→3)]‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐β‐d‐ glucopyranosyl} ester ( 3 ), and 3‐O‐{Oα‐L ‐arabinopyranosyl‐(1→2)‐Oβ‐d‐ fucopyranosyl‐(1→6)‐O‐[β‐d‐ glucopyranosyl‐(1→2)]‐β‐d‐ glucopyranosyl}‐21‐O‐{(2E,6S)‐2,6‐dimethyl‐6‐(β‐d‐ quinovopyranosyloxy)octa‐2,7‐dienoyl}acacic acid 28‐{Oα‐L ‐arabinofuranosyl‐(1→4)‐O‐[β‐d‐ glucopyranosyl‐(1→3)]‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐β‐d‐ glucopyranosyl} ester ( 4 ).  相似文献   

13.
The push‐pull activated methyl (3Z)‐4,6‐O‐benzylidene‐3‐[(methylthio)methylene]‐3‐deoxy‐α‐D‐erythro‐hexopyranosid‐2‐ulose (1) reacted with dialkyl malonate in the presence of potassium carbonate to give the alkyl (2R,4aR,6S,10bS)‐4a,6,8,10b‐tetrahydro‐6‐methoxy‐8‐oxo‐2‐phenyl‐4H‐pyrano[3′,2′:4,5]pyrano[3,2‐d][1,3]dioxine‐9‐carboxylates 2 and 3. Treatment of 1 with 3‐oxo‐N‐phenyl‐butyramide, N‐(4‐methoxy‐phenyl)‐3‐oxo‐butyramide, and 3‐oxo‐No‐tolyl‐butyramide, respectively, in the presence of potassium carbonate and 18‐crown‐6 yielded the (2R,4aR,6S,10bS)‐9‐acetyl‐7‐aryl‐4,4a,7,10b‐tetrahydro‐6‐methoxy‐2‐phenyl[1,3]dioxino‐[4′,5′:5,6]pyrano[3,4‐b]pyridin‐8(6H)‐ones 46. (2R,4aR,6S,10bS)‐4,4a,8,10b‐Tetrahydro‐6‐methoxy‐8‐oxo‐2‐phenyl‐4H‐pyrano[3′,2′:4,5]pyrano[3,2‐d][1,3]dioxine‐9‐carboxamide (7) was prepared by anellation reactions of 1 either with malononitrile or with cyanoacetamide.  相似文献   

14.
Three new phenylethyl glycosides, 3′′′′‐O‐methylmaxoside (=2‐(3,4‐dihydroxyphenyl)ethyl Oβ‐D ‐glucopyranosyl‐(1→3)‐O‐[β‐D ‐glucopyranosyl‐(1→6)]‐4‐O‐(E)‐feruloyl‐β‐D ‐glucopyranoside; 1 ), digilanatosides A (=2‐(3,4‐dihydroxyphenyl)ethyl O‐6‐O‐(E)‐sinapoyl‐β‐D ‐glucopyranosyl‐(1→3)‐4‐O‐(E)‐caffeoyl‐β‐D ‐glucopyranoside; 2 ), and digilanatoside B (=2‐(3,4‐dihydroxyphenyl)ethyl O‐6‐O‐(E)‐p‐coumaroyl‐β‐D ‐glucopyranosyl‐(1→3)‐4‐O‐(E)‐caffeoyl‐β‐D ‐glucopyranoside; 3 ) were isolated from the aerial parts of Digitalis lanata, along with two known phenylethyl glycosides, purpureaside A and maxoside, a phenylpropanoid glucose ester, 1‐O‐(E)‐feruloyl‐β‐glucopyranose, a benzoquinolethanoid glucoside, cornoside, a cardenolide, lanatoside C, a furostane‐type steroidal saponin, purpureagitoside, and a disaccharide, sucrose. Their structures were elucidated on the basis of spectroscopic evidence (1D‐ and 2D‐NMR, and HR‐MALDI‐MS).  相似文献   

15.
Two new oleanane‐type triterpene saponins, afrocyclamins A and B ( 1 and 2 , resp.), were isolated from a MeOH extract of the roots of Cyclamen africanum Boiss . & Reuter , together with three known triterpenoid saponins, lysikokianoside, deglucocyclamin I, and its dicrotalic acid derivative. The structures were elucidated, on the basis of 1D‐ and 2D‐NMR experiments and mass spectrometry as (3β,20β)‐13,28‐epoxy‐16‐oxo‐3‐{Oβ‐D ‐xylopyranosyl‐(1→2)‐Oβ‐D ‐glucopyranosyl‐(1→4)‐O‐[β‐D ‐glucopyranosyl‐(1→2)]‐α‐L ‐arabinopyranosyl}oxy}oleanan‐29‐al ( 1 ) and (3β,16α,20β)‐16,28,29‐trihydroxy‐olean‐12‐en‐3‐yl O‐4‐O‐(4‐carboxy‐3‐hydroxy‐3‐methyl‐1‐oxobutyl)‐β‐D ‐xylopyranosyl‐(1→2)‐Oβ‐D ‐glucopyranosyl‐(1→4)‐O‐[β‐D ‐glucopyranosyl‐(1→2)]‐α‐L ‐arabinopyranoside ( 2 ).  相似文献   

16.
Asprellols A–C ( 1 – 3 , resp.), three new 24‐nortriterpenoids, were isolated from the CHCl3‐soluble fraction of 95% EtOH extract of the roots of Ilex asprella, together with a known nortriterpenoid. The structures of the new compounds were elucidated as 2,6β,20β‐trihydroxy‐3‐oxo‐11α,12α‐epoxy‐24‐norursa‐1,4‐dien‐28,13β‐olide ( 1 ), 2,6β‐dihydroxy‐3‐oxo‐11α,12α‐epoxy‐24‐norursa‐1,4,20(30)‐trien‐28,13β‐olide ( 2 ), and 2,6β‐dihydroxy‐3‐oxo‐11α,12α‐epoxy‐24‐noroleana‐1,4‐dien‐28,13β‐olide ( 3 ) on the basis of spectroscopic analyses.  相似文献   

17.
Five new diterpenes, cespihypotins W–Z ( 1 – 4 , resp.) and cespihypotone ( 5 ) have been isolated from the AcOEt‐soluble fraction of the Formosan soft coral Cespitularia hypotentaculata. Two of them having the norverticillane skeleton, i.e., 1 and 2 , and the other three, 3 – 5 , possessing a verticillane skeleton. The structures were established as (+)‐(1βH,7E)‐6β,11β‐dihydroxynorverticilla‐4(18),7‐diene‐10,12‐dione ( 1 ), (+)‐(1βH,7E)‐6β‐acetoxy‐11β‐hydroxynorverticilla‐4(18),7‐diene‐10,12‐dione ( 2 ), (?)‐(1βH,7E)‐6β‐acetoxyverticilla‐4(18),7,11‐triene‐10,12‐γ‐lactone ( 3 ), (+)‐(1βH,7E)‐6β‐acetoxy‐10‐hydroxyverticilla‐4(18),7,11‐triene‐10,12‐γ‐lactone ( 4 ), and (+)‐(1βH,3Z)‐10β‐hydroxy‐6‐oxoverticilla‐3,11‐diene‐10,12‐γ‐lactone ( 5 ), respectively, on the basis of 1D‐ and 2D‐NMR spectroscopic analyses.  相似文献   

18.
Two new kaempferol glycosides, 5‐hydroxy‐2‐(4‐hydroxyphenyl)‐4‐oxo‐7‐(α‐L ‐rhamnopyranosyloxy)‐4H‐chromen‐3‐yl 2‐O‐acetyl‐3‐Oβ‐D ‐glucopyranosyl‐α‐L ‐rhamnopyranoside ( 1 ) and 5‐hydroxy‐2‐(4‐hydroxyphenyl)‐4‐oxo‐7‐(α‐L ‐rhamnopyranosyloxy)‐4H‐chromen‐3‐yl β‐D ‐glucopyranosyl‐(1→2)‐6‐O‐[(2E)‐3‐(4‐hydroxyphenyl)prop‐2‐enoyl]‐β‐D ‐glucopyranosyl‐(1→2)‐β‐D ‐glucopyranoside ( 2 ), along with ten known compounds, were isolated from the 95% EtOH extract of the whole plant of Androsace umbellata. The structures of the new glycosides were determined on the basis of detailed spectroscopic analyses, including 1D‐ and 2D‐NMR, MS, and chemical methods.  相似文献   

19.
Four novel triterpenoid saponins, Vaccariside B‐E (1–4), were isolated from the seeds of Vaccaria segetalis and their structures were elucidated as 3‐O‐β‐D‐galactopyranosyl‐(1–2)‐β‐D‐glucuronopyranosyl quillaic add 28‐O‐β‐D‐xylopyranosyl‐(1–3)‐α‐L rhamno‐pyranosyl‐(1–2)‐[α‐L‐arabinofura‐nosyl‐(1–3)]‐4‐O‐acetyl‐β‐D)‐fucopyranoside (1), 3‐O‐β‐D‐galactopyranosyl ‐ (1–2) ?3‐O‐acetyl‐β‐D ‐ glucuronopyranosyl quillaic acid 28‐O‐β‐D‐xylopyranosyl‐(1–3)‐α‐L‐rhamnopyra‐nosyl‐(1–2)‐[α‐L‐arabinofuranosyl‐(1–3)]‐4‐O‐acetyl‐β‐D‐fucopyranoside (2), 3‐O‐β‐D‐galactopyranosyl‐(1–2)‐β‐D‐glucuronopyranosyl quillaic add 28‐O‐α‐L‐arabinopyranosyl‐(1–3)‐α‐L‐rhamnopyranosyl‐(1–2)‐[α‐L‐arabinofuranosyl‐(1–3)]‐4‐O‐acetyl‐β‐D‐fucopyranoside (3), 3‐O‐β‐D‐galacto‐pyranosyl‐(1–2)‐[β‐D‐xytopyranosyl‐(1–3)]‐β‐D‐glucurono‐pyranosyl quillaic add 28‐O‐β‐D‐xylopyranosyl‐(1–3)‐α‐L‐rhamnopyranosyl‐(1–2)‐[α‐L‐arabinofuranosyl‐(1–3)]‐4‐O‐acetyl‐β‐D‐fucopyranoside (4), respectively.  相似文献   

20.
Four new triterpenoid saponins, pachystegiosides A ( 1 ), B ( 2 ), C ( 3 ), and D ( 4 ), were isolated from the roots of Acanthophyllum pachystegium K. H. Their structures were elucidated by means of a combination of homo‐ and heteronuclear 2D‐NMR techniques (COSY, TOCSY, NOESY, HSQC, and HMBC) and by FAB‐MS. The new compounds were characterized as 3‐O‐{Oβ‐D ‐galactopyranosyl‐(1→2)‐O‐[β‐D ‐xylopyranosyl‐(1→3)]‐β‐D ‐glucuronopyranosyl}quillaic acid 28‐{Oβ‐D ‐xylopyranosyl‐(1→3)‐Oβ‐D ‐xylopyranosyl‐(1→4)‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐O‐[3,4‐di‐O‐acetyl‐β‐D ‐quinovopyranosyl‐(1→4)]‐β‐D ‐fucopyranosyl}ester ( 1 ), 3‐O‐{Oβ‐D ‐galactopyranosyl‐(1→2)‐O‐[β‐D ‐xylopyranosyl‐(1→3)]‐β‐D ‐glucuronopyranosyl}quillaic acid 28‐{Oβ‐D ‐xylopyranosyl‐(1→3)‐Oβ‐D ‐xylopyranosyl‐(1→4)‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐O‐[4‐O‐acetyl‐β‐D ‐quinovopyranosyl‐(1→4)]‐β‐D ‐fucopyranosyl} ester ( 2 ), 3‐O‐{Oβ‐D ‐galactopyranosyl‐(1→2)‐O‐[β‐D ‐xylopyranosyl‐(1→3)]‐β‐D ‐glucuronopyranosyl}quillaic acid 28‐{Oβ‐D ‐xylopyranosyl‐(1→4)‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐O‐[4‐O‐acetyl‐β‐D ‐quinovopyranosyl‐(1→4)]‐β‐D ‐fucopyranosyl} ester ( 3 ), and gypsogenic acid 28‐[Oβ‐D ‐glucopyranosyl‐(1→2)‐Oβ‐D ‐glucopyranosyl‐(1→6)‐Oβ‐D ‐glucopyranosyl‐(1→3)‐β‐D ‐galactopyranosyl] ester ( 4 ).  相似文献   

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