Octanorcucurbitane and cucurbitane triterpenoids from the tubers of Hemsleya endecaphylla with HIV-1 inhibitory activity

Two new cucurbitacins, endecaphyllacins A (1) and B (2), together with six known analogues (3-8), were isolated from the tubers of Hemsleya endecaphylla. The structures of 1 and 2 were elucidated by NMR and MS spectroscopic analysis. The relative stereochemistry of 1 was determined by single-crystal X-ray diffraction. Compound 4 (cucurbitacin B) showed potent anti-HIV-1 in C8166 cells (EC=0.09 microg/mL) with a selectivity index of 16.7.     

Cucurbitane triterpenes from the fruiting bodies and cultivated mycelia of Leucopaxillus gentianeus

A reinvestigation of the fruiting bodies of the mushroom Leucopaxillus gentianeus, allowed the isolation of two minor cucurbitane triterpenes, namely, cucurbitacin D (5) and the new metabolite 16-deoxycucurbitacin B (6). The latter compound lacks an oxygenated substituent at C-16, an unprecedented structural feature among congeners of cucurbitacin B. The cucurbitanes present in the fruiting bodies were compared with those extracted from mycelia grown on the modified Melin-Norkans (MMN) culture medium. Cucurbitacins B (1) and D (5), as well as leucopaxillones A (3) and B (4), were isolated from both sources; in contrast, 16-deoxycucurbitacin B (6) and a mixture of fatty acid esters of cucurbitacin B (2) were absent in the mycelia. A new triterpene, 18-deoxyleucopaxillone A (7), was isolated from the mycelia, but was not detected in the fruiting bodies. The antiproliferative activity of the isolated triterpenes was determined against the NCI-H460 human tumor cell line, in comparison with the antitumor compound topotecan, a well-known topoisomerase I inhibitor.     

Actin-aggregating cucurbitacins from Physocarpus capitatus

Bioassay-guided fractionation of Physocarpus capitatus yielded two new cucurbitacins (3 and 4) along with the known cucurbitacin F (1) and dihydrocucurbitacin F (2). Preliminary mechanism of action studies indicate that the cucurbitacins cause actin aggregates and inhibit cell division.     

高效液相色谱测定苦味西葫芦中葫芦素的含量

目的:建立同时测定苦味西葫芦中4个葫芦素含量的HPLC分析方法。方法:采用高效液相色谱法,Kromasil C8色谱柱(150 mm×4.6 mm,ID,5μm);流动相:乙腈-水(含2.0%冰醋酸),梯度洗脱;检测波长215 nm;流速1.0 ml/min。结果:线性范围为23,24-二氢葫芦素F 0.28~5.6μg/ml(r=0.9978),23,24-二氢葫芦素D 0.39~7.8μg/ml(r=0.9986),葫芦素B 0.304~6.08μg/ml(r=0.9983),葫芦素E 2.52~50.4μg/ml(r=0.9998)。4个化合物的精密度和重现性RSD均5%,回收率均大于95%。结论:本方法可成功用于苦味西葫芦中4个葫芦素的含量测定。     

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??OBJECTIVE To study the chemical constituents from the tubers of Hemsleya penxianensis. METHODS The constituents were isolated from the tubers of H. penxianensis and purified by column chromatography, and the structures were identified by spectral analysis and chemical methods. RESULTS Five compounds were isolated from the tubers of H. penxianensis and the structures were identified as 2??,3??,16??,20, 24-pentahydroxycucurbita-5, 25(E)-diene-11,22-dione(1), cucurbitacin ??a(2), cucurbitacin ??_b(3), hemslecins G(4), and jinfushanencins B(5). CONCLUSION Compound 1 is a new compound.     

Cucurbitane glucosides from the root of Machilus yaoshansis

Seven new cucurbitane triterpene glucosides (1-5, 8, and 9) and five known analogues (6, 7, 10, cucurbitacin I 2-O-β-d-glucopyranoside, and khekadaengoside K) have been isolated from an ethanol extract of roots of Machilus yaoshansis. Compounds 1 and 2 have an unusual 16,23:22,25-diepoxy unit, 4 is an uncommon cucurbitane 25-carbamate with the carbamoyl amino group attached at C-24 to form an oxazolidinone ring in the side chain, and 8 is the first example of a trinorcucurbitane derivative. The configurations in several pairs of C-24 epimeric cucurbitacins with 24,25-dihydroxy-22-one side chains were assigned, and the validity of J(23a,24) and J(23b,24) values to differentiate the configuration at C-24 in these cucurbitane derivatives is discussed. Compounds 2-4 showed in vitro activity against protein tyrosine phosphatase 1B with IC50 values of 8.63, 2.81, and 4.26 μM, respectively. Cucurbitacin E 2-O-β-d-glucopyranoside (10) showed selective cytotoxicity against BGC-823 and A549 cancer cells with IC50 values of 4.98 and 3.20 μM, respectively.     

Novel cytotoxic diterpenes from Casearia arborea

Cytotoxicity-guided fractionation of the dichloromethane-methanol extract of the roots of Casearia arborea yielded five novel clerodane diterpenes, casearborins A-E (1-5), as well as cucurbitacin B. The presence of cucurbitacins glycosides was also detected. The absolute configuration of casearborin E was determined by X-ray crystallography.     

Cytotoxic oxylipins from a marine sponge Topsentia sp

By a bioactivity-guided fractionation, seven new oxylipins, topsentolides A(1)-C(2) (1-7), were isolated from the MeOH extract of a marine sponge Topsentia sp. Detailed NMR and MS analyses established the planar structures of these structurally related oxylipins, which are proposed to be biosynthesized by lipoxygenation followed by cyclization of unsaturated fatty acids. Acetonide derivatives and MTPA esters were prepared to elucidate the stereochemistry of topsentolides B(1) (3), B(2) (4), and C(2) (7). All compounds were tested against a panel of five human solid tumor cell lines and displayed moderate cytotoxicity.     

Globosumones A-C, cytotoxic orsellinic acid esters from the Sonoran desert endophytic fungus Chaetomium globosum

Three new esters of orsellinic acid, globosumones A-C (1-3), and three known compounds, orsellinic acid (4), orcinol, and trichodion (5), were isolated from Chaetomium globosum endophytic on Ephedrafasciculata (Mormon tea). The structures of the new compounds 1-3 were established spectroscopically, which included 2D NMR experiments and 1H NMR studies on Mosher's ester derivatives. All compounds were evaluated for inhibition of cell proliferation in a panel of four cancer cell lines, NCI-H460 (non-small cell lung cancer), MCF-7 (breast cancer), SF-268 (CNS glioma), and MIA Pa Ca-2 (pancreatic carcinoma), and normal human fibroblast cells (WI-38). Only globosumones A (1) and B (2) were found to be moderately active.     

Cytotoxic cucurbitacin constituents from Sloanea zuliaensis

A new cucurbitacin D analogue, 2-deoxycucurbitacin D (1), as well as cucurbitacin D (2) and 25-acetylcucurbitacin F (3) were isolated from Sloanea zuliaensis. Compound 1 was found only in the young leaves of the plant and not in the mature leaves, and its structure was established using spectroscopic means. Compounds 1-3 demonstrated potent cytotoxic activity against breast (MCF-7), lung (H-460), and central nervous system (SF-268) human cancer cell lines.     

Isomalabaricane-type compounds from the marine sponge Rhabdastrella aff. distincta

Fractionation of the marine sponge Rhabdastrella aff. distincta led to the isolation and characterization of four new isomalabaricane analogues, isogeoditin A (1), 13-(E)-isogeoditin A (2), isogeoditin B (3), and 22,23-dihydrostellettin B (4), along with seven known isomalabaricane derivatives (5-11). Methylation of 10 and 11 afforded methyl esters 12 and 13. The structures of compounds 1-4 were determined on the basis of spectroscopic data analysis. All compounds were tested against a small panel of human tumor cell lines.     

维药药西瓜化学成分的分离与鉴定

目的研究药西瓜Citrullus colocynthis的化学成分。方法采用硅胶、Sephadex LH-20等色谱手段结合重结晶技术进行分离纯化,通过NMR波谱数据和理化性质确定化合物的结构。结果从药西瓜中分离得到11个化合物,分别鉴定为β-谷甾醇(1)、α-菠甾醇-3-O-β-D-吡喃葡萄糖苷(2)、α-菠甾酮(3)、双-[(2-乙基)己基]邻苯二甲酸酯(4)、对羟基苯甲酸(5)、6-C-对甲基苄基牡荆素(6)、双氢葫芦素E(7)、葫芦素E(8)、异表双氢葫芦素D(9)、双氢异葫芦素B-25-乙酯(10)、葫芦素E-2-O-β-D-吡喃葡萄糖苷(11)。结论化合物6为新化合物,命名为6-C-对甲基苄基牡荆素;化合物1～5、7、9、10均为首次从该属植物中分离得到。     

土贝母化学成分研究

目的 :研究中药土贝母的化学成分。方法 :应用硅胶、C₁₈及SephadexLH-20柱色谱分离 ,物理、化学方法及光谱 (IR ,MS ,1H NMR ,¹³C NMR ,2DNMR)分析技术鉴定结构。结果 :分离并鉴定了 8个化合物 ,分别为麦芽酚(Ⅰ) ,大黄素 (Ⅱ) ,葫芦素B(Ⅲ ) ,葫芦素E(Ⅳ ) ,Δ^{7,22 ,25} 豆甾三烯 3 醇 (Ⅴ ) ,Δ^{7,22 ,25} 豆甾三烯醇 3O 十九烷酸酯(Ⅵ) ,Δ^{7,22 ,25} 豆甾三烯醇-3-O-β-D-吡喃葡萄糖苷 (Ⅶ )与Δ^{7,22 ,25} 豆甾三烯醇-3-O-β-D-(6′-棕榈酰基 )吡喃葡萄糖苷(Ⅷ )。结论 :化合物Ⅱ～Ⅷ为首次从该植物中分离得到 ,其中化合物Ⅵ ,Ⅷ为新化合物。     

A New Flavone C-glycoside from Citrullus colocynthis

Objective To study the chemical constituents of Citrullus colocynthis. Methods The chemical constituents were isolated and purified by column chromatography on silica gel and Sephadex LH-20 and recrystallization as well. NMR spectra and physicochemical property were characterized for structural identification. Results Eleven compounds were isolated and identified as β-sitosterol (1), α-spinasterol-3-O-β-D-glucopyranoside (2), α-spinasterone (3), bis (2-ethylhexyl) phthalate (4), p-hydroxybenzoic acid (5), 6-C-p-methylbenzoylvitexin (6), dihydrocucurbitacin E (7), cucurbitacin E (8), dihydro-epi-iso-cucurbitacin D (9), dihydroisocucurbitacin B-25-acaetate (10), and cucurbitacin E 2-O-β-D-glucopyranoside (11). Conclusion Compound 6 is a novel compound. Compounds 1-5, 7, 9, and 10 are isolated from C. colocynthis for the first time.     

Granulatamides A and B, cytotoxic tryptamine derivatives from the soft coral Eunicella granulata

Two new tryptamine derivatives, granulatamides A (1) and B (2), were isolated from the 2-propanol extract of the soft coral Eunicella granulata. Their structures were determined on the basis of detailed spectroscopic analysis and comparison with previously published data for similar compounds. Both compounds showed moderate in vitro cytotoxicity against a panel of 16 human tumor cell lines.     

Oligosaccharide esters from the roots of Polygala arillata

Two new sucrose esters, arillatoses A (1) and B (2), and four new trisaccharide esters, arillatoses C-F (3-6), were isolated from the roots of Polygala arillata, together with four known sucrose esters, glomeratose E (7) and sibiricoses A(1) (8), A(5) (9), and A(6) (10). The structures of the new compounds were elucidated on the basis of chemical and spectroscopic evidence.     

白木香果实中的葫芦素（英文）

目的：对白木香果实中的化学成分进行研究。方法：采用硅胶和SephadexLH-20柱色谱等方法对化合物进行分离,根据化合物的理化性质和波谱数据进行鉴定。结果：共分离纯化出5个化合物,其结构分别鉴定为葫芦苦素I（1）、葫芦素I（2）、葫芦素D（3）、异葫芦素D（4）和新葫芦素B（5）。结论：化合物1？5均为首次从沉香属植物中分离得到。化合物1,2,4和5对K562、SGC-7901和SMMC-7721显示有细胞毒活性。     

Bioactive compounds from Psorothamnus junceus

During a search for bioactive compounds from Psorothamnus junceus, four heterocyclic compounds, psorothamnone A (1), psorothamnone B (2), dalrubone (3), and emorydone (4) were isolated from the ethanol extract of the stem bark. Psorothamnones A (1) and B (2) demonstrated inhibitory activity against protein kinase C (PKC), a key enzyme involved in the signal transduction of cell proliferation and differentiation. Dalrubone (3) and emorydone (4) showed cytotoxicity against several human tumor cell lines.     

Sesquiterpene benzoxazoles and sesquiterpene quinones from the marine sponge Dactylospongia elegans

A new sesquiterpene benzoxazole, nakijinol B (3), its acetylated derivative, nakijinol B diacetate (6), and two new sesquiterpene quinones, smenospongines B (4) and C (5), were isolated from the methanol extract of the marine sponge Dactylospongia elegans. Also isolated were the known compounds dactyloquinone B and a 1:1 mixture of ilimaquinone and 5-epi-ilimaquinone. Their structures were determined on the basis of spectroscopic analyses and comparison with literature data. The isolated compounds were assessed for their cytotoxicity against a panel of human tumor cell lines (SF-268, H460, MCF-7, and HT-29) and a normal mammalian cell line (CHO-K1). All compounds were found to have activities in the range 1.8-46 μM and lacked selectivity for tumor versus normal cell lines.     

Rautandiols A and B, pterocarpans and cytotoxic constituents from Neorautanenia mitis

As part of a study on potential antitumor agents from rainforest plants, two new pterocarpans, rautandiol A (1) and rautandiol B (2), together with eight known compounds, were isolated from Neorautanenia mitis. Among the compounds isolated, rotenone (3) and 12-hydroxyrotenone (4) showed significant cytotoxic activity with IC(50) values of 0.008-0.010 and 0.04-0.06 microg/mL against MCF-7 and A-549 cells, respectively.