New citrinin derivatives isolated from Penicillium citrinum

Three new coupling compounds derived from citrinin (9) and 2,3,4-trimethyl-5,7-dihydroxy-2,3-dihydrobenzofuran (8) – penicitrinone A (1), penicitrinol A (2) and penicitrinone B (3) – and a new citrinin derivative – decarboxydihydrocitrinin (4) – were isolated along with 3-methoxy-1-methyl-4(1H)-quinolone (5), quinolactacin A2 (6), dihydrocitrinone (7), 2,3,4-trimethyl-5,7-dihydroxy-2,3-dihydrobenzofuran (8), citrinin (9), quinocitrinin A or B (10), and decarboxydihydrocitrinone (11) from the extract of Penicillium citrinum IFM 53298. The relative structures of compounds 1–4 were confirmed on the basis of spectroscopic investigations and chemical correlations. Citrinin (9) and quinolactacin A2 (6) both showed antifungal activity.     

Two new flavonol glycosides from the leaves of Cleome chelidonii L.f.

From the leaves of Cleome chelidonii L.f., two new flavonol glycosides, named cleomesides A (1) and B (2), and four known compounds, quercetin 3-O-β-glucopyranosyl(1 → 2)-α-rhamnoside-7-O-α-rhamnoside (3), ethyl α-galactopyranoside (4), adenine (5) and glycerol monostearate (6), were isolated. The structures of all isolated compounds (1–6) were determined by NMR spectroscopy and mass spectrometry. The data of known compounds (3–6) were further compared with the reported data for these compounds.     

灰毡毛忍冬化学成分的研究

从灰毡毛忍冬(Lonicera mocranthoide Hand. -Mazz.)花的乙醇提取物的正丁醇溶解部分分得三个常春藤皂甙元的双糖链甙,其中一个为已知化合物川续断皂甙乙(dipsacoside B,Ⅰ);另外两个为新化合物,分别命名为灰毡毛忍冬皂甙甲(macranthoidin A,Ⅱ)和灰毡毛忍冬皂甙(nmcranthoidin B,Ⅲ),两者的次级皂甙灰毡毛忍冬次皂甙甲(macranthoside A,Ⅱb)和灰毡毛忍冬次皂甙乙(macranthoside B,Ⅲb),亦未见报道。     

牛蒡子化学成分的研究

从牛蒡(Arctium lappa L.)子乙醚和丙酮提取物中,经硅胶柱层析,低压柱层析和制备性薄层层析分离到一个甾体化合物,胡萝卜甙(daucosterol,Ⅰ)和四个已知木脂素:牛蒡子甙元(arctigenin,Ⅱ)、牛蒡子甙(arctiin,Ⅲ)、罗汉松脂素(matairesinol,Ⅳ)和牛蒡酚F(lappaol F,Ⅴ)。一个新木脂素,命名为新牛蒡素乙(neoarctin B,Ⅵ)。根据光谱(UV,IR,¹H-NMR,¹³C-NMR,DEPT,2D-NMR和MS)分析,推定了其化学结构为式Ⅵ。     

Two new flavonoids from Selaginella uncinata

Two new flavonoids, uncinataflavones A (1) and B (2), along with one known compound 6-(5-carboxyl-2-methoxyphenyl)-apigenin (3), were isolated from Selaginella uncinata (Desv.) Spring. All these compounds belong to apigenin derivatives with aryl substituents at C-6 position. The structures of new compounds were elucidated on the basis of comprehensive spectroscopic analyses (UV, IR, 1D, and 2D NMR as well as HR-ESI-MS).     

流感病毒神经氨酸酶抑制剂筛选模型的建立和应用

目的建立适用于高通量筛选的流感病毒神经氨酸酶(neuraminidase,NA)抑制剂筛选模型。方法从甲型及乙型流感病毒中制备神经氨酸酶,以2′-(4-methylumbelliferyl)-α-D-N-acetylneuraminic acid(MUNANA)作为底物,建立检测神经氨酸酶活性的荧光测定法及其抑制剂体外筛选方法,用高通量筛选系统对1 200个化合物与提取物进行初筛。结果神经氨酸酶酶促反应以pH 3.5,二价阳离子浓度为2～6 mmol·L^-1及37℃孵育时酶活性最佳;甲、乙型流感病毒不同株神经氨酸酶的米氏常数(Km)的范围为(4.89～5.94) μmol·L^-1;初筛发现12个化合物对流感病毒神经氨酸酶有可重复的抑制活性。结论优化了神经氨酸酶反应体系,建立的体外模型可用于抗甲、乙型流感病毒药物的高通量筛选及酶抑制动力学的研究。     

斩龙剑中新苯丙素甙的结构鉴定

从玄参科植物斩龙剑(Veronivastrum sibirica (L.)Pennell.)的根部分得九种化学成分,分别为斩龙剑甙A(sibiriosideA,Ⅰ)斩龙剑甙B(sibiriosideB,Ⅱ),异阿魏酸(isoferulicacid,Ⅲ),6-(4-methoxyferulpol)mioporoside(Ⅳ),scrophularioside(Ⅴ),6-O-阿魏酰梓醇(6-O-trans-feruloylcatalpol,Ⅵ),阿魏酸(ferulicacid,Ⅶ),胡萝卜甾醇(daucosterol,Ⅷ)和β-谷甾醇(Ⅸ)。其中斩龙剑甙A和斩龙剑甙B为新苯丙素甙化合物,应用波谱分析和理化数据测定,确定了它们的结构。     

Two new neuroprotective phenolic compounds from Gastrodia elata

Two new phenolic compounds 4-(4′-hydroxybenzyl) phenyl glucoside (gastrodin B, 1) and 1′-hydroxymethyl-phenyl 4-hydroxy-3-(4″-hydroxybenzyl) benzyl ether (gastrol B, 2) were isolated from the rhizomes of Gastrodia elata. Their structures were elucidated on the basis of spectroscopic data and chemical reaction. All compounds exhibited potent neuroprotective activity against H₂O₂-induced PC12 cell damage.     

Inhibition of protein tyrosine phosphatase 1B by triterpenes isolated from Potentilla discolor Bge

Seven oleanene triterpenes were isolated from the roots of Potentilla discolor Bge and their structures were identified as3-oxoolean-12-en-27-oic acid (1), gypsogenic acid (2), 3α-hydroxyolean-12-en-27-oic acid (3), 3β-hydroxyolean-12-en-27-oic acid (4), aceriphyllic acid A (5), aceriphyllic acid A methyl ester (6), and oleanolic acid (7). Compounds 1–7 inhibited protein tyrosine phosphatase 1B (PTP1B) activity, with IC₅₀ values ranging from (7.5±0.5) to (22.7±0.5) μmol/L. Among the isolates, compounds 1, 2, 3 and 7 from thePotentilla discolor Bge were found to exhibit selective PTP1B inhibitory activity.     

New phenylpropanoid esters of sucrose from <Emphasis Type="Italic">Polygonum hydropiper</Emphasis> and their antioxidant activity

By various chromatographic methods, two new phenylpropanoid esters of sucrose named hidropiperosides A (1) and B (2), and three known compounds as vanicosides A (3), B (4), and E (5) were isolated from the methanolic extract of the whole plant of Polygonum hydropiper L. (Polygonaceae). Their structures were elucidated by extensive spectroscopic methods including 1D-and 2D-NMR experiments, as well as ESI-MS analysis. All the isolated compounds were tested for their antioxidant activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay system. Among them, compounds 2 and 3 showed significant antioxidant activity with their SC₅₀ values of 23.4 and 26.7 μg/mL, respectively.     

Structural analogues of cumambrin B from the flower ofChrysanthemum boreale

The structural analogues of cumambrin B (1, 2, 3, 4) were isolated from the flower ofChrysanthemum boreale Makino. The structures of compounds were determined by two-dimensional¹H-¹H COSY and¹³C-¹H COSY spectra with the aid of homonuclear and heteronuclear double resonance experiment. The stereochemistry of compounds has been verified from single crystal X-ray diffraction of cumambrin A (2). The antimicrobial activities of these guaianolides have been studied.     

Five new compounds from Dendrobium crystallinum

Five new compounds, dencryol A (1), dencryol B (2), crystalltone (3), crystallinin (4), and 3-hydroxy-2-methoxy-5,6-dimethylbenzoic acid (5), together with six known compounds, dendronobilin B (6), syringic acid (7), apigenin (8), isoviolanthin (9), 6?-glucosyl-vitexin (10), and palmarumycin JC2 (11), have been isolated from the stems of Dendrobium crystallinum, of which compounds 9–11 were isolated from the genus Dendrobium for the first time, and all the other compounds were first obtained from this plant. Their structures were established on the basis of spectroscopic analysis and literature data.     

SIRT1 inhibitory compounds from the roots of Codonopsis pilosula

Three new compounds, pilosulinene A (1), pilosulinols A (2), and B (3), along with seven known compounds, were isolated from the roots of Codonopsis pilosula cultivated in Xundian County of Yunnan Province. The structures of new compounds were established by spectroscopic methods. In particular, the presence of an aromatic ring in the structure of 1 makes it intriguing. The inhibitory activity of compounds against SIRT1 was evaluated. The results showed that 8 could inhibit Sirt1 in a dose-dependent manner.     

红花锦鸡儿地上部分抗HIV化学成分的研究

为了研究红花锦鸡儿(Caragana rosea)地上部分的化学成分，寻找具有抗HIV作用的药用成分。在抗HIV生物活性指导下，利用色谱技术进行分离纯化，从红花锦鸡儿地上部分的乙酸乙酯提取部位分得5个化合物，根据理化性质和波谱技术进行结构鉴定，分别鉴定为myricetin(1)，mearnsetin(2)，对羟基桂皮酸(3)，cararosinol A(4)，cararosinol B(5)，并推测了cararosinol B与该植物中发现的另一白藜芦醇四聚体kobophenol A的转化关系。化合物4和5为新的白藜芦醇四聚体，化合物1～3为首次从该植物中分得。上述化合物体外均无明显的抑制HIV作用。     

Cytotoxic triterpenoides from Alismatis Rhizoma

Four prostane-type triterpenes were isolated from a methanol extract of Alismatis Rhizoma by bioassay-guided isolation using in vitro cytotoxic assay. The compounds were identified as alisol B 23-acetate (1), alisol C 23-acetate (2), alisol B (3), alisol A 24-acetate (4) by spectroscopic methods. Amongst the compounds, alisol B (3) showed significant cytotoxicity against SK-OV3, B16-F10, and HT1080 cancer cell lines with ED50 values of 7.5, 7.5, 4.9 microg/ml, respectively.     

Secoiridoids and xanthones from Tylophora secamonoides Tsiang

A new secoiridoid, secamonoide A (1), and a new xanthone glycoside, secamonoide B (2), together with nine known compounds, were isolated from the aerial parts of Tylophora secamonoides Tsiang. Their structures were elucidated on the basis of spectroscopic methods. An antimicrobial bioassay showed that secamonoides A and B exhibited weak activities (MIC values greater than 100 mg/ml) against some hospital bacteria in vitro.     

Three new Phlegmariurine B type lycopodium alkaloids from Huperzia serrata

Phlegmariurine B ( 1 ), a known alkaloid, along with three new analogous compounds, 2 f -hydroxyphlegmariurine B ( 2 ), 2-oxoyphlegmariurine B ( 3 ) and 11-oxophlegmariurine B ( 4 ), were isolated from the CHCl 3 fraction of total alkaloids of whole plant of the Chinese medicinal herb Huperzia serrata . Their structures were elucidated by spectral analysis.     

Two new dimeric secoiridoid glycosides from the fruits of Ligustrum lucidum

Two new secoiridoid glycosides, ligusides A and B (1 and 2), as well as seven known compounds (3–9), were isolated from the fruits of Ligustrum lucidum. Their structures were elucidated on the basis of spectroscopic and chemical analysis.     

Studies on the chemical constituents of Ilex pubescens

Three new compounds, ilexisochromane (1), ilex acid A (2), and ilex acid B (3), were isolated from the roots of Ilex pubescens. Their structures were elucidated using the combination of 1- and 2-D NMR and mass spectrometry analyses.     

New lignan glycosides from Cupressus duclouxian (Cupessaceae)

From the branches and leaves of Cupressus duclouxiana two new lignan glycosides named cupressoside A (1) and cupressoside B (2), together with matairesinoside (3), dihydrodehydrodiconiferyl alcohol (4), dihydrodehydrodiconiferyl alcohol-9-O-α-l-rhamnopyranoside (5), dihydrodehydrodiconiferyl alcohol-4-O-α-l-rhamnopyranoside (6), ( ? )-isolariciresinol (7) and ( ? )-isolariciresinol-9-O-β-d-xylopyranoside (8), were isolated. The structures of these compounds were determined on the basis of their HR-FAB-MS, IR, UV, ¹H and ¹³C NMR (DEPT), and 2D NMR (HMQC, HMBC, COSY, NOESY) spectral data.