黑刺菝葜中的甾体皂苷

从黑刺菝葜(Smitax scobinicaulis C.H.Wringh)根茎中再次分离得到2个新的甾体皂苷化合物,经理化、光谱分析及与标准样品对照,鉴定化合物Ⅲ为(25D)螺甾-5-烯-3β,17α,27-三羟基-3-O-β-D-吡喃葡萄糖-(1→4)-O-[α-L-吡喃阿拉伯糖(1→6)]-β-D-吡喃葡萄糖甙。化合物Ⅳ为(25D)螺甾-3β,17α,27-三羟基-3-O-β-D-吡喃葡萄糖-(1→4)-O-[α-L-吡喃阿拉伯糖(1→6)]-β-D-吡喃葡萄糖甙。     

排风藤中皂苷类化学成分研究

从茄属植物排风藤的全草中分离得到了4个皂苷类化合物,经鉴定分别为:25R-螺甾-3-O-[β-D-吡喃木糖基-(1→3)]-O－β-D-吡喃葡萄糖基-(1→2)-O-β-D-吡喃葡萄糖基-(1→4)-O-β-D-吡喃半乳糖苷(1),5α,25R-螺甾-3-O-[β-D-吡喃木糖基-(1→3)]-O-β-D-吡喃葡萄糖基-(1→2)-O－β-D-吡喃葡萄糖基-(1→4)-O-β-D-吡喃半乳糖苷(2),22α,25R-26-O-β-D-吡喃葡萄糖基-22-羟基-呋甾-△5-3β,26-二醇-3-O-β-D-吡喃葡萄糖基-(1→2)-O-[β-D-吡喃木糖基-(1→3)]-O-β-D-吡喃葡萄糖基-(1→4)-O-β-D-吡喃半乳糖苷(3),22α,25R-26-O-β-D-吡喃葡萄糖基-22-羟基-呋甾-△5-3β,26-二醇-3-O－β-D-吡喃葡萄糖基-(1→2)-O-β-D-吡喃葡萄糖基-(1→4)-O-β-D-吡喃葡萄糖苷(4).化合物1-4均为首次从排风藤中分离得到.     

蒺藜中甾体皂苷TTS-12提取分离工艺研究

对蒺藜全草中-抗真菌甾体皂苷：替告皂苷元3-O-β-D．吡喃木糖(1→2)-[β-D-吡喃木糖(1→3)]-β-D-吡喃葡萄糖(1→4)．[α-L-吡喃鼠李糖(1→2)]-β-D-吡喃半乳糖甙苷(TTS-12)进行提取分离工艺研究,采用70％乙醇提取后,沉淀部分经乙酸乙酯处理再进行硅胶柱层析,粗品重结晶后得到TTS-12纯品,HPLC-ELSD法测定TTS-12含量,TTS-12的收率为86．5％,产品纯度为97．1％。本工艺简便实用,收率稳定,产品纯度高,适合中试生产TTS-12。     

知母中甾体皂苷类成分的研究(英文)

从中药知母(Anemarrhena asphodeloides Bge.)的70%乙醇提取物中分离得到6个化合物,经波谱学方法和与已知样品对照鉴定为:3-O-β-D-glucopyranosyl-(1→2)-β-D-galactopyranosyl-(3β,5β)-pregn-16(17)-ene-20-one(1)、timosaponin AIII(2)、timosaponin BIII(3)、22-hydroxy-5β-furost-3β,15α-diol-3-O-β-D-glucopyranosyl(1→2)-β-D-galactopyranoside(4)、timosaponin G(5)、β-daucosterol(6)。其中化合物1为新天然产物,命名为知母孕甾A,是知母中首次发现的C21甾体类化合物,经HR ESI-MS、1D NMR、2D NMR确定其结构,并首次对其核磁数据进行归属。     

传统中药漆姑草（Sagina japonica）中的C-27甾体成分

利用Diaion HP 20及硅胶柱层析进行化合物的分离,从乙酸乙酯萃取部位分离得到了4个化合物,借助多种光谱技术进行结构鉴定分别鉴定为(25R)-螺甾-5-烯-1β,3β-二醇1-O{O-α-L-鼠李吡喃糖苷-(1→2)-O-[β-D-木糖吡喃糖苷-(1→3)]1β-D-岩藻吡喃糖苷}(ophiopogonin D,1),(25R)-ruscogenin 1-O-[2-O-(乙酰基)-α-L-鼠李吡喃糖苷-(1→2)][β-D-木糖吡喃糖苷-(1→3)]-β-D-岩藻吡喃糖苷(2),(25R)-rascogenin 1-O-[3-0-(乙酰基)-α-L-鼠李吡喃糖苷-(1→2)][β-D-木糖吡喃糖苷-(1→3)]-β-D-岩藻吡喃糖苷(3),蜕皮甾酮(4).所有化合物均为首次从该植物中分得.     

油菜蜂花粉中皂苷化学成分的研究

油菜蜂花粉煮沸灭酶,减压蒸干,用80%乙醇提取,经AB-8大孔树脂、MCI柱和ODS反相柱层析柱分离,得到4个皂苷类化合物,通过理化方法、1H NMR、13C NMR等手段鉴定他们的化学结构,分别为:3,22-二羟基,3-O-β-D-葡萄糖-齐墩果烷(1)、3,22-二羟基,3-O-β-D-吡喃葡萄糖基(1→2)-β-D-吡喃葡萄糖基-[-β-D-吡喃葡萄糖(1→6)]-齐墩果烷(2)、3,22-二羟基,3-O-β-D-吡喃葡萄糖基(1→2)-β-D-吡喃葡萄糖基-[-β-D-吡喃葡萄糖(1→6)]-齐墩果酸(3)和3-O-β-D-葡萄糖-谷甾醇苷(4)。其中,皂苷1～3在油菜蜂花粉中首次报导。     

滇产植物皂素成分的研究——Ⅹ.五指莲的两个新甾体皂甙(1)

从重楼属植物五指莲Paris axialis H.Li.根茎中分离到三个甾体皂甙,经化学降解,质谱,核磁共振谱分析,证明其中两个甙为新的化合物,即偏诺皂甙元-3-O-β-D-葡萄吡喃糖基(1→3)[α-L-鼠李吡喃糖基(1→2)]-β-D-葡萄吡喃糖甙(Ⅰ)和24α-羟基偏诺皂甙元-3-O-β-D-葡萄吡喃糖基(1→3)][α-L-鼠李吡喃糖基(1→2)]-β-D-葡萄吡喃糖(Ⅲ);另一个鉴定为薯芋皂甙元-3-O-β-D-葡萄吡喃糖基(1→3)[α-L-鼠李吡喃糖基(1→2)]-β-D-葡萄吡喃糖甙(Ⅱ)。     

龙舌兰发酵叶汁中的一个新甾体皂苷

从龙舌兰（Agave americana)的发酵叶汁中分离到一个新甾体皂苷。结合波谱和化学方法,新化合物的结构鉴定为替告皂苷元3－O－α－L－鼠李吡喃糖基－（1→3)－β-D-葡萄吡喃糖基－（1→2）-[β-D-葡萄吡喃糖基－（1→3)-β－D－葡萄吡喃糖基－（1→4）－β－D－半乳吡喃糖苷。     

裂果薯的化学成分研究——皂甙甲和乙

从裂果薯(Tacca plantaginea Drenth)中分离到甲、乙、丙三个甾体化合物。化物合甲和乙,经光谱解析和化学分析鉴定为两个新甾体皂甙。其中裂果薯皂甙甲(Ⅱ)为一个糖连接方式上不常见的皂甙(约茂皂甙元-3-O-β-D-吡喃葡萄糖(1→2)[α-L-吡喃鼠李糖(1→3)][α-L-吡喃鼠李糖(1→4)]-β-D-吡喃葡萄糖甙);裂果薯皂甙乙(Ⅲ)(约茂皂甙元-3-O-α-L-吡喃鼠李糖(1—2)[α-L-吡喃鼠李糖(1→3)]-β-D-吡喃葡萄糖甙)。丙为豆甾醇甙。     

蜘蛛抱蛋属中甾体皂甙的分布

在文献资料和实验研究的基础上,本文总结了甾体皂甙在蜘蛛抱蛋属植物中的分布。发现单羟基的薯蓣皂甙元的配糖体一蜘蛛抱蛋皂甙(薯蓣皂甙元-3-O[β-D-葡萄吡喃糖基(1→2)]-[β-D-木吡喃糖基(1→3)]-β-D-葡萄吡哺糖基(1→4)-β-D-半乳吡哺糖甙),广泛存在于所研究过的这些植物中,而且是大部植物根茎的主要皂甙。它是蜘蛛抱蛋属植物的特征化学成分,表明该属是一个自然类群,甾体皂甙对它是有分类学意义的。     

Structural studies of the capsular polysaccharide produced by Leuconostoc mesenteroides ssp. cremoris PIA2

The structure of the capsular polysaccharide (CPS) produced by Leuconostoc mesenteroides ssp. cremoris PIA2 has been determined using component analysis and NMR spectroscopy. (1)H and (13)C resonances were assigned using 2D NMR experiments, and sequential information was obtained by (1)H,(1)H-NOESY and (1)H,(13)C-HMBC experiments. The CPS consists of linear pentasaccharide repeating units with the following structure: →3)-β-D-Galf-(1→6)-β-D-Galf-(1→2)-β-D-Galf-(1→6)-β-D-Galf-(1→3)-β-D-Galp-(1→, in which four out of the five sugar residues have the furanoid ring form, a structural entity found in bacteria but not in mammals. The analysis of the magnitude of the homonuclear three-bond coupling constants of the anomeric protons for the five-membered sugar rings indicates that the sugar residues substituted at a primary carbon atom show one kind of conformational preferences, whereas those substituted at a secondary carbon atom show another kind of conformational preferences.     

Structure of the O-polysaccharide of Pragia fontium 27480 containing 2,3-diacetamido-2,3-dideoxy-d-mannuronic acid

The following structure of the O-polysaccharide of Pragia fontium 27480 was elucidated by sugar analysis, including determination of the absolute configurations of the monosaccharides, and Smith degradation along with 1D and 2D (1)H and (13)C NMR spectroscopy: →4)-β-d-ManpNAc3NAcA-(1→2)-α-l-Rhap-(1→3)-β-l-Rhap-(1→4)-α-d-GlcpNAc-(1→ where ManNAc3NAcA stands for 2,3-diacetamido-2,3-dideoxymannuronic acid.     

Structure of the O-polysaccharide from the lipopolysaccharide of Providencia alcalifaciens O48

An O-polysaccharide was isolated by mild acid degradation of the lipopolysaccharide of Providencia alcalifaciens O48 and studied by sugar and methylation analyses along with (1)H and (13)C NMR spectroscopy, including 2D COSY, TOCSY, ROESY and (1)H,(13)C HSQC and HMBC experiments. It was found that the polysaccharide is acidic and has a linear mono-O-acetylated tetrasaccharide repeating unit with the following structure: →3)-α-D-Manp-(1→2)-α-L-Fucp-(1→2)-β-D-GlcpA4Ac-(1→3)-α-D-GalpNAc-(1→.     

Passibiflorin,epipassibiflorin and passitrifasciatin: cyclopentenoid cyanogenic glycosides from Passiflora

An epimeric mixture of two novel cyclopentenoid cyanogenic glycosides, passibiflorin [1-(6-O-β-D-rhamnopyranosyl-β-D-glucopyranosyloxy)-4-hydroxycyclopent-2-en-1-nitrile] and its C-1 epimer, epipassibiflorin, has been isolated from Passiflora biflora and P. talamancensis. The structures were determined by means of ¹H NMR and ¹³C NMR. Another novel cyclopentenoid cyanogenic glycoside, passitrifasciatin [1-(4-O-β-D-rhamnopyranosyl-β-D-glucopyranosyloxy)-4-hydroxycyclopent-2-en-1-nitrile] is described from Passiflora trifasciata. The structure was determined by means of ¹H NMR. The identification of the sugar moieties was made by HPLC and TLC. The isolation of a β-1 → 4 and a β-1 → 6-rhamnoglucoside of cyclopentenoid cyanogens from three species of subgenus Plectostemma of Passiflora suggests that diglycosides of this type are taxonomically diagnostic for the section.     

小花盾叶薯蓣甙的酶降解

从小花盾叶薯蓣(Dioscorea parviflora C. T. Ting)的新鲜根状茎中分离到一个新的呋甾烷型配糖体,命名为小花盾叶薯蓣甙(parvifloside) (1),其结构通过波谱和化学方法鉴定为:(25R)-26-O-β-glucopyranosyl-furost-5-en-3β, 22ξ, 26-triol 3-O-β-D-glucopyranosyl (1→3)-β-D-glucopyranosyl (1→4)-[α-L-rhamnopyranosyl (1→2)]-β-D-glucopyranoside.化合物1在纤维素酶粗酶和β-葡萄糖苷酶中进行水解,得到降解产物2-7.对1的酶解现象进行了讨论.同时,对所分离的甾体皂甙的抗稻瘟霉菌活性进行了初步筛选.     

Costusoside-I and costusoside-J,two new furostanol saponins from the seeds of Costus speciosus

The structure of costusoside I and costusoside J have been established as 3-O-{β-d-glucopyranosyl (1 → 2)-α-l-rhamnopyranosyl (1 → 2) [α-l-rhamnopyranosyl (1 → 4)]-β-d-glucopyranosyl}-26-O-(β-d-glucopyranosyl)-22α-methoxy 25 R)-furost-5-en-3β, 26-diol and its 22-hydroxy compound respectively, isolated fron the seeds of Costus speciosus.     

Structural elucidation of an α-1,2-mannosidase resistant oligosaccharide produced in Pichia pastoris

The N-glycosylation pathway in Pichia pastoris has been humanized by the deletion of genes responsible for fungal-type glycosylation (high mannose) as well as the introduction of heterologous genes capable of forming human-like N-glycosylation. This results in a yeast host that is capable of expressing therapeutic glycoproteins. A thorough investigation was performed to examine whether glycoproteins expressed in glycoengineered P. pastoris strains may contain residual fungal-type high-mannose structures. In a pool of N-linked glycans enzymatically released by protein N-glycosidase from a reporter glycoprotein expressed in a developmental glycoengineered P. pastoris strain, an oligosaccharide with a mass consistent with a Hexose(9)GlcNAc(2) oligosaccharide was identified. When this structure was analyzed by a normal-phase high-performance liquid chromatography (HPLC), its retention time was identical to a Man(9)GlcNAc(2) standard. However, this Hexose(9)GlcNAc(2) oligosaccharide was found to be resistant to α-1,2-mannosidase as well as endomannosidase, which preferentially catabolizes endoplasmic reticulum oligosaccharides containing terminal α-linked glucose. To further characterize this oligosaccharide, we purified the Hexose(9)GlcNAc(2) oligosaccharide by HPLC and analyzed the structure by high-field one-dimensional (1D) and two-dimensional (2D) (1)H NMR (nuclear magnetic resonance) spectroscopy followed by structural elucidation by homonuclear and heteronuclear 1D and 2D (1)H and (13)C NMR spectroscopy. The results of these experiments lead to the identification of an oligosaccharide α-Man-(1 → 2)-β-Man-(1 → 2)-β-Man-(1 → 2)-α-Man-(1 → 2) moiety as part of a tri-antennary structure. The difference in enzymatic reactivity can be attributed to multiple β-linkages on the α-1,3 arm of the Man(9)GlcNAc(2) oligosaccharide.     

Structure of the O-specific polysaccharide of Proteus vulgaris O15 containing a novel regioisomer of N-acetylmuramic acid, 2-acetamido-4-O-[(R)-1-carboxyethyl]-2-deoxy-D-glucose

An acidic O-specific polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of Proteus vulgaris O15 and studied by sugar and methylation analyses along with 1H and 13C NMR spectroscopy, including 2D COSY, TOCSY, ROESY, and H-detected 1H,(13)C HMQC experiments. The polysaccharide was found to contain an ether of GlcNAc with lactic acid, and the following structure of the repeating unit was established:-->3)-alpha-D-GlcpNAc4(R-Lac)6Ac-(1-->2)-beta-D-GlcpA-(1-->3)-alpha-L-6dTalp2Ac-(1-->3)-beta-D-GlcpNAc-(1-->where L-6dTal and D-GlcNAc4(R-Lac) are 6-deoxy-L-talose and 2-acetamido-4-O-[(R)-1-carboxyethyl]-2-deoxy-D-glucose, respectively. The latter sugar, which to our knowledge has not been hitherto found in nature, was isolated from the polysaccharide by solvolysis with anhydrous triflic acid and identified by comparison with the authentic synthetic compound. Serological studies with the Smith-degraded polysaccharide showed an importance of 2-substituted GlcA for manifesting of the immunospecificity of P. vulgaris O15.     

Structural studies of the lipopolysaccharide of Moritella viscosa strain M2-226

The structure of the O-specific side chain of the lipopolysaccharide from the Gram-negative psychrophilic bacterium Moritella viscosa strain M2-226, responsible for the winter ulcer in Atlantic salmon, has been determined. Monosaccharide analysis and (1)H and (13)C NMR spectroscopy were employed to elucidate the structure. It was concluded that the polysaccharide is composed of a trisaccharide repeating unit with the following structure: →3)-β-D-GlcpNAc-(1→4)-[α-D-GlcpA-(1→3)]-α-L-Fucp-(1→ .     

Structures of verbascoside and orobanchoside,caffeic acid sugar esters from Orobanche rapum-genistae

The complete structural elucidation of the two caffeic acid sugar esters verbascoside and orobanchoside, has been realized by ¹H and ¹³C NMR studies. It has been demonstrated that verbascoside is β-(3′,4′-dihydroxyphenyl)ethyl-O-α-L-rhamnopyranosyl(1→3)-β-D-(4-O-caffeoyl)-glucopyranoside, and orobanchoside is β-hydroxy-β-(3′,4′-dihydroxyphenyl)-ethyl-O-α-L-rhamnopyranosyl(1→2)-β-D-(4-O-caffeoyl)-glucopyranoside.