Biomedical subjects

Han-Dong Sun

Publications and source records attributed to Han-Dong Sun.

At least 55 records · Page 3Linked to original sources

PubMed2005

Three new compounds from Isodon melissoides.

Reinvestigation of the aerial parts of Isodon melissoides has afforded two new ent-diterpenoids, melissoidesins V (1) and W (2), together with five known ones, glabcensin W (3), melissoidesin C (4), melissoidesin A (5), melissoidesin B (6) and melissoidesin D (7), one new ionone derivative 3alpha,4alpha-isopropyliden-beta-ionol (8), as well as three analogues, 3-hydroxy-4-oxo-beta-ionol (9), megastigma-7-en-3,5,6,9-tetraol (10) and blumenol A (11), and three phenolic compounds salicylic acid (12), syringic acid (13) and cirsiliol (14). The new structures were elucidated on the basis of spectroscopic techniques, especially the 2D-NMR spectral analysis.

Chromatography, Gel↗

PubMed2005

Complete NMR assignments of the antibacterial biflavonoid GB1 from Garcinia kola.

From the antibacterial fraction of the roots of Garcinia kola, 3'',4',4''',5,5'',7,7''-heptahydroxy-3,8''-biflavanone (GB1) was isolated as the major constituent, whose interesting conformations were studied on the basis of its 1D and 2D NMR spectra obtained at different temperatures and in different solvents. GB1 showed antibacterial activities against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) with MIC of 32 and 128 microg/ml, respectively.

Biflavonoids↗

PubMed2005

Two new icetexane diterpenoids from Salvia przewalskii.

Two new icetexane diterpenoids, przewalskin C, D (1, 2), together with sixteen known diterpenoids, were isolated from Salvia przewalskii. Eight of known ones (compounds 3, 12-18) were reported firstly from this plant. To the best of our knowledge, it's the first report of icetexane diterpenoids from this plant. The identification and structural elucidation of these compounds were based on 1D- and 2D-NMR spectral data analysis.

Diterpenes↗

PubMed2005

[Studies on chemical constituents from rhizome of Impatiens pritzellii var. hupehensis].

OBJECTIVE: To study the chemical constituents from the rhizome of Impatiens pritzellii var. hupehensis. METHOD: The rhizome were extracted with methanol, isolated and purified by column chromatography on silica gel. All the compounds were identified on the basis of spectral analysis (including IR, MS, NMR) and physico-chemical characters. RESULT: Five compounds were identified as a-spinasterol (I), alpha-spinasteryl-7, 22-dien-3-O-beta-D-glucopyranoside (II), stigmast-7, 22-dien-3-one (III), stearic acid (IV), hentriantane (V). CONCLUSION: Compound I is isolated from this plant for the first time, Compound II, III, IV, V are isolated from genus Balsaminaceae for the first time.

Impatiens↗

PubMed2004

Maoecrystal V, cytotoxic diterpenoid with a novel C19 skeleton from Isodon eriocalyx (Dunn.) hara.

Maoecrystal V (1), a novel C(19) diterpenoid possessing a unique 6,7-seco-6-nor-15(8-->9)-abeo-5,8-epoxy-ent-kaurane skeleton, was isolated from the leaves of a Chinese medicinal herb, Isodon eriocalyx. Its structure was determined by comprehensive NMR and MS spectroscopic analysis and confirmed by single-crystal X-ray diffraction study. Compound 1 showed remarkable inhibitory activity toward HeLa cells with IC(50) = 0.02 microg/mL (cis-platin: IC(50) = 0.99 microg/mL).

Crystallography, X-Ray↗

PubMed2004

Coriatone and corianlactone, two novel sesquiterpenes from Coriaria nepalensis.

Both coriatone (1). a novel highly oxygenated picrotoxane-type sesquiterpene, and corianlactone (2). with an unprecedented sesquiterpene basic skeleton, named coriane, were isolated from Coriaria nepalensis Wall. The structures of 1 and 2 were determined by analysis of their two-dimensional NMR data, and the structure of 2 was confirmed by X-ray analysis. Compounds 1 and 2 showed no remarkable inhibitory activity toward K(562) cells. They are cytotoxic with IC(50) > 50 microg/mL (cis-platinim: IC(50) = 0.49 microg/mL).

Crystallography, X-Ray↗

PubMed2004

Cytotoxic isoprenylated xanthones from Cudrania tricuspidata.

Eight new isoprenylated xanthones, cudratricusxanthones A-H (1-8), were isolated from the roots of Cudrania tricuspidata, together with ten known compounds, cudraxanthones H (9) and M (10), xanthone V(1a) (11), toxyloxanthone C (12), macluraxanthone B (13), 1-hydroxy-3, 6, 7-trimethoxyxanthone (14), cycloartocarpesin (15), artocarpesin (16), cudraflavone B (17), and kaempferol (18). Their structures were characterized by spectroscopic methods. Xanthones 5, 7, 10, and 12 showed inhibitory effects on four kinds of human digestive apparatus tumor cell lines (HCT-116, SMMC-7721, SGC-7901, and BGC-823) with IC(50) values of 1.6-11.8 microg/mL. Xanthones 2, 4, and 11 displayed significant cytotoxicity against HCT-116, SMMC-7721, and SGC-7901 (IC(50)=1.3-9.8 microg/mL). Flavonoids 15-17 were almost inactive.

Antineoplastic Agents↗

PubMed2004

ent-Kaurene diterpenoids from Isodon oresbius.

Three new ent-kaurene diterpenoids, oreskaurins A-C (1-3), together with ten known ent-kaurene diterpenoids, enmenin monoacetate (4), effusanin E (5), adenolin B (6), maoecrystal G (7), enmelol (8), trichokaurin (9), sodoponin (10), trichorabdal A (11), nodosin (12), enmein (13), and a flavonoid, vitexin (14), were isolated from Isodon oresbius. Their structures were determined by spectroscopic means. Compound 12 showed inhibitory activity toward K562 cells with IC(50)=1.43 microg/ml.

Diterpenes, Kaurane↗

PubMed2004

Lancifodilactones B-E, new nortriterpenes from Schisandra lancifolia.

Four new nortriterpenes, lancifodilactones B-E (1-4), were isolated from the leaves and stems of Schisandra lancifolia. Their structures were determined by analysis of 1D and 2D NMR spectroscopic data. These compounds are members of a new highly oxygenated cycloartane skeletal class with a biosynthetically modified eight-membered ring D.

China↗

PubMed2004

Diterpenoids from Isodon melissoides.

Nine new diterpenoids, melissoidesins M-U (1-9), along with five known analogues, melissoidesin F (10), xindongnin B (11), melissoidesin G (12), melissoidesin E (13), and dawoensin A (14), were isolated from the aerial parts of Isodon melissoides. The structures of new compounds were elucidated by analysis of spectral evidence including extensive 2D NMR data. Compounds 2, 3, 7, 11, 12, and 14 showed cytotoxicity against the human tumor BGC-823 cell line with IC(50) values less than 10 microg/mL, respectively.

Antineoplastic Agents, Phytogenic↗

PubMed2004

New isoprenylated flavones, artochamins A--E, and cytotoxic principles from Artocarpus chama.

Five new isoprenylated flavones, artochamins A-E (1-5), together with eight known flavones (6-13), were isolated from the roots of Artocarpus chama. All structures were elucidated by spectroscopic methods. Artonin E (12) showed strong cytotoxicity against 1A9 (ovarian), significant activity against MCF-7 (breast adenocarcinoma), and moderate activity against HCT-8 (ileocecal) and MDA-MB-231 (breast adenocarcinoma) tumor cell lines. Artochamin C (3) was more potent against MCF-7, 1A9, HCT-8, and SK-MEL-2 (melanoma) than A549 (lung carcinoma), KB (epidermoid carcinoma of the nasopharynx), and its drug-resistant (KB-VIN) variant. Artocarpin (6) displayed weak but relatively broad inhibitory effects compared with 3 and 12.

Antineoplastic Agents, Phytogenic↗

PubMed2004

Three new oxetane-ring-containing taxoids from Taxus chinensis.

Three new 14beta-benzoyloxy taxoids containing an oxetane ring, namely, 14beta-benzoyloxybaccatin IV (1), 14beta-benzoyloxy-13-deacetylbaccatin IV (2), and 14beta-benzoyloxy-2-deacetylbaccatin VI (3), have been isolated from the leaves and stems of Taxus chinensis. Their structures were elucidated on the basis of 1D and 2D NMR spectroscopic data.

Cyclization↗

PubMed2004

Flavonoids and coumarins from Leaves of Phellodendron chinense.

Three new compounds, phellodensin G, phellodenols D and E have been isolated from the leaves of Phellodendron chinense Schneid (Rutaceae), together with thirteen known compounds. Their structures were established by means of spectroscopic analysis, including extensive 2D NMR and mass spectra.

Coumarins↗

PubMed2004

Cytotoxic ent-kaurane diterpenoids from Isodon rubescens var. rubescens.

Five new ent-kauranoids, xindongnins C - G ( 1 - 5), together with five known ones, xindongnins A and B ( 6 and 7), melissoidesin G ( 8), dawoensin A ( 9), and glabcensin V ( 10), were isolated from the leaves of Isodon rubescens var. rubescens, and structurally elucidated. Compounds 1, 4, and 6 - 10 showed inhibitory effects against human tumor K562 cells with IC (50) values ranging from 0.3 to 7.3 microg/mL. The structure of 6 was revised on the basis of its 2D-NMR spectral data.

Antineoplastic Agents, Phytogenic↗

PubMed2004

Two new coumarin derivatives from the roots of Heracleum rapula.

Two new coumarins, 13- O-[ beta- D-apiofuranosyl(1-->6)- beta- D-glucopyranosyl]-(12 R)-heraclenol ( 1) and (12 R,12" R)-diheraclenol ( 2) were isolated from the acetone extract of the fresh roots of Heracleum rapula. Their structures were determined by means of spectroscopic analysis and, in the case of compound 1, the structure elucidation was supported by acid hydrolysis. Compound 1 is a coumarin glycoside while 2 is a coumarin dimer. The inhibitory effects of 1, its aglycone ( 3), and 2 on rabbit platelet aggregation induced by PAF, AA and ADP were tested. Weak activities were observed for each compound with the percentages of inhibition in the range of 0.7 - 24.8 %.

Animals↗

PubMed2004

Structural elucidation of fritillahupehin from bulbs of Fritillaria hupehensis Hsiao et K.C. Hsia.

A novel diterpenoid ester, fritillahupehin (1) and three known fatty acids, palmitic acid (2), lignoceric acid (3) and azelaric acid (4), have been isolated from the bulbs of Fritillaria hupehensis Hsiao et K.C. Hsia. The structure of fritillahupehin has been established to be ent-kauran-16beta-yl lignocerate by means of spectroscopic and chemical evidence. Compounds 2-4 were isolated from Fritillaria sp. for the first time.

Diterpenes↗

PubMed2004

Cytotoxic ent-kauranoids from Isodon leucophyllus.

Two new compounds, baiyecrystals D and E (1, 2), together with eight known analogues, xerophilusin B (4), macrocalin B (5), oridonin (6), rosthorin A (7), lasiocarpanin (8), rabdoternin A (9) and phyllostachysin A (10) and B (11), were isolated from the aerial parts of Isodon leucophyllus. The structures of 1 and 2 and 4-11 were elucidated on the basis of spectroscopic methods, especially the 2D NMR spectral analysis. Compounds 2, 6-8 and 10 were evaluated for their antineoplastic activities in vitro. Among them, lasiocarpanin (8) showed significant inhibitory activities against K562 and Bcap37 cells, with the IC50 values of 0.13 and 1.26 microg mL(-1), respectively, which were lower than those of the positive control.

Antineoplastic Agents, Phytogenic↗

PubMed2004

Ent-kaurane diterpenoids from Isodon rubescens var. rubescens.

Five new ent-kaurane diterpenoids xindongnins H-L (1-5), together with five known ones, xindongnins A and B (6, 7), melissoidesins G (8), dawoensin A (9), and glabcensin V (10) were isolated from Isodon rubescens var. rubescens. Their structures were elucidated by spectroscopic methods including extensive 2D NMR techniques.

Diterpenes, Kaurane↗