Antifungal jujubogenin saponins from Colubrina retusa.

Antifungal assay-guided isolation of the 95% ethanol extract of the stems of Colubrina retusa yielded jujubogenin 3-O-alpha-L-arabinofuranosyl(1-->2)-[beta-D-glucopyranosyl (1-->3)]-alpha-L-arabinopyranoside (1), which showed modest growth-inhibitory effects against Candida albicans, Cryptococcus neoformans, and Aspergillus fumigatus (MICs, 50 microg/mL). In addition, two new minor saponins, jujubogenin 3-O-alpha-L-arabinofuranosyl(1-->2)-[2-O-(trans, cis)p-coumaroyl-beta-D-glucopyranosyl(1-->3)]-alpha-L-arabinopy ranosi de (2), and jujubogenin 3-O-(5-O-malonyl)-alpha-L-arabinofuranosyl (1-->2)-[beta-D-glucopyranosyl(1-->3)]-alpha-L-arabinopyranoside (3), were obtained. Saponin 2 was marginally active against only C. neoformans, with a MIC of 50 microg/mL, while 3 was inactive. NMR spectroscopy was used extensively for the structure determination of these compounds. The previously reported ambiguity of the NMR assignments of jujubogenin saponins for carbons -26 to -29 was clarified by a comprehensive analysis of the NMR spectra of 1.     

New jujubogenin glycosides from Colubrina asiatica

Three new jujubogenin glycosides, namely, 3' '-O-acetylcolubrin (1); 3' ',2' "-O-diacetylcolubrin (2), and 3' '-O-acetyl-6' '-O-trans-crotonylcolubrin (3), were isolated from the leaves of Colubrina asiatica, in addition to the known colubrin, rutin, and kaempferol 3-O-rutinoside. Compounds 1-3 were isolated and purified via a combination of chromatographic procedures, and determined structurally using spectroscopic methods.     

凹叶瑞香中的香豆素成分

目的：对凹叶瑞香（Daphne retusa）的化学成分进行研究。方法：利用硅胶柱色谱,Sephadex LH-20和RP18反相柱色谱的方法分离和纯化化合物,通过光谱方法及理化性质鉴定化合物结构。结果：从凹叶瑞香氯仿部位分离得到8个香豆素类成分,分别为7-羟基香豆素（1）,7-甲氧基-8-羟基香豆素（2）,7-羟基-8-甲氧基香豆素（3）,双白瑞香素-7-O-β-D-葡萄糖苷（4）,伞形花内酯-7-O-β-D-葡萄糖苷（5）,结香苷A和C（6和7）,【8,8’-bi-2H-1-benzopyran]-2,2’dione,7’-（α—D—glu—copyranosyloxy）-7-hydroxy-3-[（2-OXO-2H-1-benzopyran-7-y1）oxy]（8）。结论：所有化合物均为首次从该植物中分得。     

苦瓜中新葫芦烷型皂苷的研究

目的研究苦瓜的化学成分。方法采用乙醇提取、大孔吸附树脂纯化和硅胶柱色谱分离,通过光谱分析鉴定化合物的结构。结果从苦瓜中分离并鉴定了2对异构体。经13C-NMR光谱分析,其中一对异构体的化学结构初步确定为19R-5β,19环氧葫芦烷-6,23,25-三烯-3β,19-二醇(Ⅰa)和19S-5β,19环氧葫芦烷-6,23,25-三烯-3β,19-二醇(Ⅰb);另一对异构体的化学结构确定为5β,19环氧葫芦烷-6,23,25-三烯-3-O-吡喃葡萄糖苷(Ⅱa)和5β,19环氧葫芦烷-6,23,25-三烯-3-O-阿洛吡喃糖苷(Ⅱb)。结论化合物Ⅰa、Ⅰb、Ⅱa、Ⅱb均为首次从苦瓜中分离得到的新化合物。     

Cytotoxic triterpenoids from Maytenus retusa

Seven new triterpenoids (1-7) and 36 known compounds were isolated from the root bark of Maytenus retusa. Their structures were determined by 1D and 2D spectroscopic studies. Several compounds were evaluated for their cytotoxicity against the human tumor cell lines HL-60 and MCF-7. Some of them were cytotoxic, with IC(50) values ranging between 0.2 and 4.7 μM.     

New antimycobacterial and antimalarial 8,9-secokaurane diterpenes from Croton kongensis

Two new 8,9-secokaurane diterpenes, ent-8,9-seco-7alpha,11beta-diacetoxykaura-8(14),16-dien-9,15-dione (1) and ent-8,9-seco-8,14-epoxy-7alpha-hydroxy-11beta-acetoxy-16-kauren-9,15-dione (2), together with two known compounds, ent-8,9-seco-7alpha-hydroxy-11beta-acetoxykaura-8(14),16-dien-9,15-dione (3) and ent-7beta-hydroxy-15-oxokaur-16-en-18-yl acetate, were isolated from Croton kongensis. This is the first report on the presence of 8,9-secokauranes in the plant genus Croton. Diterpenes 1-3 exhibited antimycobacterial activity with minimum inhibitory concentrations (MICs) of 25.0, 6.25, and 6.25 microg/mL, respectively, and possessed antimalarial activity with IC(50) ranges of 1.0-2.8 microg/mL. They also demonstrated comparable cytotoxicity toward the Vero (IC(50) ranged from 0.9 to 3.2 microg/mL), KB (IC(50) from 1.2 to 13.8 microg/mL), and BC cell lines (IC(50) from 1.1 to 2.2 microg/mL, except for compound 1, which was inactive against BC cells).     

An acetylated bidesmosidic saponin from Schefflera octophylla.

A new acetylated bidesmosidic triterpenoid saponin has been isolated from the leaves of Schefflera octophylla and structurally elucidated as 3-epi-betulinic acid 3-O-beta-D-6'-acetylglucopyranoside 28-[alpha-L-rhamnopyranosyl(1----4)-O-beta-D-glucopyranosyl(1----6)]-bet a-D-0-glucopyranoside [1].     

A new triterpenoidal saponin from Acacia auriculiformis.

A new triterpenoidal saponin has been isolated from an aqueous EtOH extract of the legumes of Acacia auriculiformis and characterized as 3-O-([beta-D-xylopyranosyl(1----3)-beta-D-xylopyranosyl(1----4)-alpha-L- rhamnopyranosyl(1----2)]-[alpha-L-rhamnopyranosyl(1----4)]-beta-D- glucopyranosyl)-3,16,21-trihydroxyolean-12-en-28-oic acid [1] by chemical studies and spectral data.     

A new triterpene saponin from Pittosporum viridiflorum from the Madagascar rainforest.

A novel triterpenoid saponin, pittoviridoside (1), which possesses an unusual 2,3,4-trisubstituted glycosidic linkage, has been isolated from Pittosporum viridiflorum using the engineered yeast strains 1138, 1140, 1353, and Sc-7 for bioactivity-guided fractionation. The structure of this compound was determined to be 3-O-[beta-D-glucopyranosyl(1-->2)]-[alpha-D-arabinopyranosyl(1-->3)],[alpha-l-arabinofuranosyl(1-->4)-beta-D-glucuronopyranosyl-21-angeloyl-22-senecioylolean-12-en-3beta,15alpha,16alpha,21beta,22alpha,28-hexol by spectral, chemical, and GC analyses. This compound showed weak cytotoxicity against the A2780 human ovarian cancer cell line.     

A new saponin from Deeringia amaranthoides

A new triterpenoid saponin, 3-O-[alpha-L-rhamnopyranosyl (1----3)-beta-D-glucuronopyranosyl]-28-O-[beta-D-xylopyranosyl (1----2)-beta-D-glucopyranosyl]-3 beta-hydroxyolean-12-en-28-oate [3] has been isolated together with two known saponins, 3-O-[alpha-L-rhamnopyranosyl (1----3)-beta-D-glucuronopyranosyl]-3 beta- hydroxyolean-12-en-28-oic acid [1] and 3-O-[alpha-L-rhamnopyranosyl (1----3)-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-3 beta- hydroxyolean-12-en-oate [2], from the fruits of Deeringia amaranthoides.     

Bidentatoside I, a new triterpene saponin from Achyranthes bidentata.

Bidentatoside I (1) is a new triterpene saponin bearing an unusual dioxopropionic acid unit, isolated from the roots of Achyranthes bidentata. Structural elucidation was performed mainly by chemical and homo- and heteronuclear 2D NMR techniques. This compound did not show any potentiation of the in vitro cytotoxicity of cisplatin in the HT 29 human colon cancer cell line.     

A cytotoxic triterpene saponin from the root bark of Aralia dasyphylla.

A novel triterpene saponin (1) was isolated from an ethanol extract of the root bark of Aralia dasyphylla. Its structure was elucidated as 3-O-[beta-D-glucopyranosyl (1-->3)-beta-D-galactopyranosyl(1-->2)]-beta-D-glucuronopyranosyl- ole anolic acid-28-O-beta-D-glucopyranoside, according to spectral and chemical evidence. Compound 1 showed significant cytotoxic activity against KB and Hela-S(3) cells.     

A new triterpenoid saponin from Isolatocereus dumortieri

A new triterpenoid saponin, named dumortierinoside A, was isolated from Isolatocereus dumortieri. The structure was determined as dumortierigenin 3-O-alpha-L-rhamnopyranosyl (1-->2)-beta-D-glucopyranosyl(1-->2)-beta-D-glucuronopyranoside (1) on the basis of NMR and mass spectroscopy.     

从单条草中分得一个新的三萜皂苷

目的：对报春花科珍珠菜属药用植物单条草Lysimachia candida的化学成分进行研究。方法：采用硅胶柱层析进行分离和纯化，通过波谱和化学方法进行结构鉴定。结果：从正丁醇萃取部分分离出1个三萜皂苷类化合物，结构鉴定为：3β,16α-羟基齐墩果－12－烯－28－醛－3－O－β－D－吡喃葡萄糖基－23－O－α－D－呋喃核糖苷，命名为单条草苷甲（1），结论：单条草苷甲是新结构的三萜皂苷。     

鹿药新呋甾皂苷的分离鉴定及活性研究

目的:研究鹿药Smilacina japonica根茎及根的化学成分及活性.方法:采用超声提取,柱色谱分离与纯化,根据理化性质及红外、质谱、一维、二维核磁共振等波谱方法鉴定结构,进行了体外抗肿瘤活性测定.结果:分离得到1个化合物,鉴定为26-O-β-D-吡喃葡萄糖基-(25R)-呋甾-5-烯3β,12,17α,22ζ,26-五醇-12-O-乙酰基-3-O-α-L-吡喃鼠李糖基-(1→2)-β-D-吡喃葡萄糖苷(1),该化合物具有抑制入肺腺癌SPC-A-1细胞生长的活性.结论:化合物1为新化合物.     

Homopseudopteroxazole,a new antimycobacterial diterpene alkaloid from Pseudopterogorgia elisabethae

In the course of our study to find novel antimycobacterial secondary metabolites from Caribbean gorgonian octocorals, we have isolated a new diterpene alkaloid, namely, homopseudopteroxazole (1), as a minor constituent of the hexane extract from the sea plume Pseudopterogorgia elisabethae. Its structure was deduced by interpretation of combined spectroscopic data, including extensive 1D and 2D NMR measurements, and NMR spectral comparisons with known amphilectane models. Biological screening studies indicate that homopseudopteroxazole (1) is a strong growth inhibitor of Mycobacterium tuberculosis H(37)Rv.     

Screening of some New Caledonian and Vanuatu medicinal plants for antimycobacterial activity

Twenty plants, belonging to sixteen families, used in traditional New Caledonian and Vanuatu medicine for treatment of symptoms potentially related to tuberculosis (cough, fever or inflammation) were screened for antimycobacterial activity. We also screened an original endemic plant, Amborella trichopoda, only member of the monogeneric family Amborellaceae and considered the most primitive living angiosperm. In total, 55 extracts were evaluated for inhibitory activity against Mycobacterium bovis BCG strain at a concentration of 100 microg/ml. Methanolic and dichloromethane extracts of Amborella trichopoda, Codiaeum peltatum, Myristica fatua, and essential oils Myoporum crassifolium showed an activity at this concentration. Methanolic extract of Amborella trichopoda fruits presented a significant activity with a minimal inhibitory concentration included between 1 and 2.5 microg/ml. In the same conditions, this activity was comparable with those of the reference drugs pyrazynamide and ethambutol, at 20 and 2.5 microg/ml, respectively.     

Tetrahdroxysqualene from Rhus taitensis shows antimycobacterial activity against Mycobacterium tuberculosis

Tuberculosis has become a major health problem, in particular with the emergence of extremely drug resistant tuberculosis (XDRTB). In our search for new therapeutic leads against TB, we isolated a new triterpene (1) from the plant Rhus taitensis collected in Papua New Guinea. Tetrahydroxysqualene (1) was isolated using bioassay-guided fractionation of the methanolic extract of R. taitensis leaves and twigs. The structure of tetrahydroxysqualene (1) was elucidated on the basis of HRESIMS and 1D and 2D NMR spectra. Tetrahydroxysqualene (1) exhibited antituberculosis activity with an MIC of 10.0 microg/mL, while showing only modest cytotoxicity.     

A new bioactive steroidal saponin from Sansevieria cylindrica

A new steroidal saponin was isolated from the leaves of Sansevieria cylindrica. Its structure was established as (3beta,12beta,15alpha,25S)-26-(beta-D-glucopyranosyloxy)-22-hydroxyfurost-5-en-3-yl 12-O- (6-deoxy-alpha-L-mannopyranosyl)-15-O-(6-deoxy-alpha-L-mannopyranosyl)-beta-D-glucopyranoside. The structural identification was performed using detailed analyses of (1)H and (13)C NMR spectra including 2D NMR spectroscopic techniques (COSY, HETCOR, HMBC and HMQC) and chemical conversions. The steroidal saponin showed no haemolytic effects in the in vitro assays and demonstrated inhibition of the capillary permeability activity.