Two new glycosides from the seeds of Cassia obtusifolia

Two new glycosides,nor-rubrofusarin-6-O-β-D-(6′-O-acetyl)glucopyranoside(1) and 1-desmethylaurantio-obtusin-2-O-β-D-glucopyranoside (2) were isolated from the seeds of Cassia obtusifolia and their structures were established by chemical and spectral evidences.     

A new spirostanol saponin from the rhizomes of Paris mairei

A new spirostanol steroidal saponin,named maireioside A(1),together with three known steroidal saponins,hypoglaucin G(2), parisaponin I(3),and diosgenin-3-O-α-L-rhamnopyranosyl(1→4)-[α-L-rhamnopyranosyl(1→2)]-β-D-glucopyranoside(4),were isolated from the rhizomes of Paris mairei.The structure elucidation was accomplished by 1D and 2D NMR methods,HR-ESI-MS, and hydrolysis.     

Synthesis ofα-D-GlcpNAc-（1→2）-[α-D-ManpNAc-（1→3）-]α-L-Rhap-（1→2）-α-L-Rhap-（1→3）-α-L-Rhap,the repeating unit of O10 antigen from Acinetobacter baumannii

An efficient synthesis ofα-D-GlcpNAc-（1→2）-[α-D-ManpNAc-（1→3）-]α-L-Rhap-（1→2）-α-L-Rhap-（1→3）-α-L-Rhap（1）, the repeating unit of the O10 antigen from Acinetobacter baumannii was achieved via sequential assembly of the building blocks,p- methoxylphenyl 2,4-di-O-benzoyl-α-L-rhamnopyranoside（2）;2-O-allyloxycarbonyl-3,4-di-O-bcnzoyl-α-L-rhamnopyranosyl tri- chloroacetimidate（3）;4-methoxylphenyl 3-O-allyloxycarbonyl-4-O-benzoyl-α-L-rhanmopyranoside（4）;2-azido-3-O-benzoyl-2- deoxy-4,6-O-isopropylidene-α-D-mannopyranosyl trichloroacetirnidatc（5）;2-azido-3,4,6-tri-O-benzoyl-2-deoxy-α,β-D-glucopyr- ano syl trichloroacetimidatc（6）.The total yield of 1 from 4 was 4.7%.     

Flavonoid triglycosides from the seeds of Camellia oleifera Abel

Two flavonoid triglycosides, kaempferol 3-O-{ β-D-glucopyranosyl-（1→2）-[α-L-rhamnopyranosyl-（1→ 6）]-β-D-glucopyranoside} （1） and kaempferol 3-O-{ β-D-xylopyranosyl-（1 → 2）-[α-L-rhamnopyranosyl-（1→6）]-β-D-glucopyranoside } （2）, were isolated from the seed of Camellia oleifera Abel. The absolute configuration of compound 1 was established on the basis of its X-ray analysis. Their cytotoxic activities and anti-HIV-RT activities were evaluated.     

Synthesis of di-and tetrasaccharide containing 6-deoxytalose from the O-antigenic polysaccharide of B. pseudomallei strain 304b

Synthesis of the disaccharide β-D-Glup-(1→3)-6-deoxy-α-L-Talp Ⅱ,and its dimer Ⅲ from the O-antigenic polysaccharide of Burkholderia pseudomallei strain 304b,were achieved through assembly of suitably synthesized building blocks,4-methoxylphenyl 6-deoxy-2,4-di-O-benzoyl-α-L-talopyranoside (7),3-O-allyl-2,4,6-tri-O-benzoyl-α,β-D-glucopyranosyl trichloroacetimidate (8) and 2,3,4,6-tetra-O-benzoyi-α,β-D-glucopyranosyl trichloroacetimidate (Ⅱ).The total yield of Ⅲ from 4-methoxyiphenyl 2,3-O-isopropylidene-α-L-rhamnopyranoside (1) was 18%.     

A new C27-steroidal glycoside from Ophiopogon japonicus

A new C27-steroidal glycoside with three known compounds were isolated from the tuber of Ophiopogonjaponicus （Thunb.） Ker-Gawl. Based on the spectral analysis, including HRMS, 1H NMR, 13C NMR, DEPT, 1H-1H COSY, HMQC and HMBC, their chemical structures were determined as pennogenin-3-O-α-L-rhamnopyranosyl-（1→ 2）-β-D-xylopyranosyl-（1→ 4）-13-D-gluco- pyranoside （1）, pennogenin-3-O-α-L-rhamnopyranosyl-（1→ 2）-β-D-glucopyranoside （2）, ophiopojaponin C （3） and ophiopogonin D （4）. 2007 Jian Zhong Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.     

Two triterpene glycosides from the sea cucumber Bohadschia marmorata Jaeger

Further studies on the sea cucumber Bohadschia marmorata Jaeger led to the isolation of a new holostan-type triterpene glycoside,Marmoroside C（1）together with a known triterpene glycoside（2）.On the basis of spectroscopic analyses,including two- dimensional NMR techniques,and chemical reactions,the structure of the new triterpene glycoside was elucidated as 3-O-[3-O- methyl-β-D-glucopyranosyl-（1→3）-β-D-glucopyranosyl-（1→4）-β-D-quinovopyranosyl-（1→2）-4-O-sodium-sulfato-β-D-xylo- pyranosyl]-25-acetoxy-22-oxo-9（11）-holostene-3β,12α,17α-triol.     

Two new phenolic glycosides from the aerial parts of Androsace umbellata

Two new phenolic glycosides,2-hydroxy-4-O-β-D-glucopyranosylphenylacetic acid methyl acetate(1) and 2-hydroxy-4-O-β-D-glucopyranosylphenylacetic acid(2) were isolated from the aerial parts of Andwsace umbellata.Their structures were elucidated by spectral techniques.     

A new glycoside from Polygala tenuifolia Willd

A new tdterpenoid glycoside, 3-β-O-β-D-glucopyranosyl presenegenin 28-O-α-L-arabipyranosyl（1 → 3）-6-β- xylopyranosyl（1 → 4）-[β-D-apiofuranosyl（1 → 3）]-Ct-L-rhamnopyranosyl（1 → 2）-[α-L-rhamnopyranosyl（1 → 3）]-β-D-fucopyranosyl ester （1） was isolated from the Polygala tenuifolia Willd., together with two known saponins, including polygalasaponinXXIV （2） and polygalasaponinXXVIII （3）. The structure of new compound was elucidated by spectroscopic methods.     

New ent-kaurane-type diterpenoids from Isodon nervosus

Two new ent-kaurane-type diterpenoids,6β,7β,13α-trihydroxy-1α-acetoxy-7α,20-epoxy-ent-kaur-16-en-15-one（1）and 15β- hydroxy-6,7-seco-6,11β：6,20-diepoxy-1α,7-olide-ent-kaur-16-ene（2）were isolated from the Isodon nervosus,and the structures were elucidated by spectroscopic analysis.     

薤中新的甾体皂苷类化学成分

从薤(Allium chinense G. Don)的乙醇提取物中分离得到6个新甾体皂苷类化合物, 通过波谱数据及理化性质分析, 鉴定其分别为5α-cholano-22,16-内酯-3-O-β-D-吡喃葡萄糖基-(1→2)-[β-D-吡喃葡萄糖基-(1→3)]-β-D-吡喃葡萄糖基(1→4)-β-D-吡喃半乳糖苷(1)、 6-酮-5α-cholano-22,16-内酯-3-O-β-D-吡喃木糖基-(1→4)-[α-L-吡喃阿拉伯糖基-(1→6)]-β-D-吡喃葡萄糖苷(2)、 (25R)-26-O-β-D-吡喃葡萄糖基-5α-呋喃甾烷-3β,26-二醇-3-O-β-D-吡喃葡萄糖基-(1→2)-[β-D-吡喃葡萄糖基-(1→3)]-β-D-吡喃葡萄糖基(1→4)-β-D-吡喃半乳糖苷(3)、 (25R)-6-酮-26-O-β-D-吡喃葡萄糖基-5α-呋喃甾烷-3β,22α,26-三醇-3-O-α-L-吡喃木糖基-(1→4)-β-D-吡喃葡萄糖苷(4)、 (25R)-6-酮-5α-呋喃甾烷-3β,22α,24β,26-四醇-3-O-β-D-吡喃木糖基-(1→4)-[α-L-吡喃阿拉伯糖基-(1→6)]-β-D-吡喃葡萄糖苷(5)和(25R)-5α-呋甾-2α,3β,22α, 26-四醇-26-O-β-D-吡喃葡萄糖苷(6). 化合物1和2的皂苷元骨架在天然产物中首次分离得到. 选用H₂O₂诱导PC12细胞神经氧化损伤模型, 初步考察了6种新的呋甾型化合物的抗氧化活性, 实验结果表明, 化合物3对由H₂O₂诱导的细胞氧化损伤有显著的保护效果.     

Two new steroidal glucosides from Ophiopogon.japonicus （L.f.） Ker-Gawl

Two new steroidal glucosides, 26-O-β-D-glucopyranosyl （25S）-furost-5-ene-1β,3β,22α,26-tetraol l-O-β-D-xylopyranosyl- （1 → 3）-[α-h-rhamnopyranosyl-（1 → 2）]-[β-D-fueopyranoside and （25R） spirost-5-ene-3β,14α-diol-3-β-O-β-L-rhanmopyranosyl- （1 → 2）-[β-D-xylopyranosyl（1 → 4）]-[-β-D-glucopyranoside, were isolated from the Ophiopogon japonicus （L.f.） Ker-Gaw. Their structures were elucidated by spectroscopic methods.     

Cytotoxic triterpenoid saponins from Ardisia pusilla

A new triterpenoid saponin,3-O-{β-D-xylopyranosyl-(1→2)-β-D-glucopyranosyl-(1→4)-[β-D-ghcopyranosyl-(1→2)]-α-L-arabinopyranosyl }-3β,16α,28α-trihydroxy-1313,28-epoxy-oleanan-30-al(ardipusilloside Ⅲ,1),together with two known sapo-nins,ardisiacrispins A(2)and B(3),were isolated from the whole plants ofArdisia pusilla A.DC.Their structures were elucidated by extensive spectral analysis and chemical evidences.Saponins 1 and 3 exhibited significant cytotoxicity against human glioblastoma U251MG cells.     

Two new steroidal glycosides from Ophiopogon japonicus

Two new C27-steroidal glycosides were isolated from the fibrous roots of Ophiopogon japonicus. The spectral analysis and chemical evidence revealed their chemical structures to be （25R）-spirost-5,14-dien-3β-yl-O-α-L-rhamnopyranosyl-（1 → 2）-β-D- xylopyranosyl-（1 → 4）-β-D-glucopyranoside （1） and ophiogenin 3-O-β-D-glucopyranoside （2）.     

A new C21 steroid glycoside from Marsdenia tenacissima

A new C21 steroid glycoside,11α-O-tigloyl-12-β-O-acetyl tenacigenin B 3-O-β-D-glucopyranosyl-（1→4）-β-D-glucopyr- anosyl-（1→4）-3-O-methyl-6-deoxy-β-D-allopyranosyl-（1→4）-β-D-oleandropyranoside（1）,named tenacissoside N was isolated from the stems of Marsdenia tenacissima.The structure of the glycoside was identified by HR-ESI-MS and NMR spectra.     

A new glycoside from the leaves of Neoalsomitra integrifoliola

A new ionone glycoside （6R,9R）-blumenyl α-L-rhamnopyranosyl-（1 → 6）-β-D-gluco-pyranoside （1）, together with a new natural product 2-methoxyl-4-trans-pmpenyl-phenol α-L-rhamnopyranosyl-（1 → 6）-β-D-glucopyranoside （2）, was isolated from the leaves ofNeoalsomitra integrifoliola. Their structures were elucidated by chemical and spectral analysis. Compound 1 showed weak anti-inflammatory and low-level antioxidant activities.     

Two new diterpenoids from Isodon eriocalyx

Isodoneriocalyx(Dunn)Hara(Labiatae).Ithasbeenusedasfolkmedicinetotreatsorethroat,inflammationaswellasreducingbloodpressure'.Previousstudiesonthisgenushaverevealed,anumberofditerpenoidspossessvariousbioactivitiessuchasanti-tUmorandanti-bacterial='3act...     

A new cycloartane nortriterpenoid from Quercus variabilis Blume

The leaves and stems of Quercus variabilis Blume afforded a new cycloartane nortriterpenoid,3α-acetyloxy-4α,14α-dimethyl-9β, 19-cycloergost-24-oic acid(1),along with five known compounds(2-6).The structure of 1 was elucidated by 1D and 2D NMR and mass spectroscopy.     

SYNTHESIS OF α-AMINO-β-(4-IMIDAZOLYL)-ETHYLPHOSPHONIC ACID,THE PHOSPHONOISOSTERE OF HISTIDINE

A short synthesis starting from 4-imidazolylmethanol(2)was developedfor the phosphonoisostere of histidine,-amino-β-(4-imidazolyl)-ethylphosphosphonic acid,His(P)(1).The synthesis features Wittig-Hornerreaction of aldehyde(4)with diphosphonate(5)followed by selectivedetritylation with 50% formic acid.     

Two new kaempferol glycosides from the seeds of Camellia semiserrata Chi

Two new acetylated kaempferol glycosides were isolated from the seeds of Camellia semiserrata Chi,their structures were elucidated as kaempferol-3-O-[(3-O-acetyl)-α-L-rhamnopyranosyl(1→3)(4-O-acetyl)-α-L-rhamnopyranosyl(1→6)-β-D-glucopyranoside] (1) and kaempferol-3-O-[(2-O-acetyl)-α-L-rhamnopyranosyl(1→3)(4-O-acetyl)-α-L-rhamnopyranosyl(1→6)-β-D-gluco -pyranoside](2) by spectral experiments(including ESI-MS,1D- and 2D-NMR).