Biomedical subjects
Publications and source records attributed to Han-Dong Sun.
Three new prenylated phenolic compounds, fornicins A-C (1-3), were obtained from the fruiting bodies of Ganoderma fornicatum. The structure elucidation was achieved by interpretation of spectroscopic data. These compounds exhibited moderate cytotoxic activity with IC(50) values of 15 to 30 microg/mL in Hep-2 cells.
Two new abietane diterpenoids, yunnannin A and danshenol C, were isolated from Salvia yunnanensis together with ten known diterpenoids, danshenol A, przewalskin, tanshinone IIA, tanshinone I, crypotanshinone, 1,2-dihydrotanshinone, tanshinlactone, 5,6-dehydrosugiol, 12-hydroxy-6,7-seco-8,11,3-abietatriene-6,7-dial and phytol. Their structures were established based on spectroscopic data, chemical reactions and comparison with literature data. Compounds were tested for their antitumor activity in T-24, QGY, K562, Me180 and BIU87 cell lines. Compound showed inhibited growth of K562 (IC50=0.53 microg/mL), T-24 (IC50=7.94 microg/mL), QGY (IC50=4.65 microg/mL) and Me180 (IC50=6.89 microg/mL) cell lines while compound was inactive. Compound showed moderate inhibitory activity on QGY (IC50=16.75 microg/mL) and Me180 (IC50=5.84 microg/mL) cells.
A phytochemical investigation on the leaves of Isodon parvifolius yielded three new ent-abietanoids parvifolines L-N (1-3), together with five known ent-abietanoids (4-8) and one known ent-labdane diterpenoid (9). Their structures were determined on the basis of extensive spectroscopic analysis.
This paper reviewed the worldwide research progresses of the genus Laggera both on phytochemical and pharmacological work in the past few decades. The main secondary metabolites of this genus are proved to be sesquitepenoids, flavonoids and phenolic acids. Phamacological investigations revealed that the certain extracts of some Laggera species possess significant bioactivities on anti-inflammation, anti-tumor and anti-viral infection. This review afforded the comprehensive description of the active components as to provide useful references to elucidate their historical clinical application on upper respiratory infection, influenza, parotitis, and recurrent herpes viral infection.
Semnostachya menglaensis Tsui (Acanthaceae) is a rare plant indigenous to Mengla in the tropical rainforest of the Xishuangbanna prefecture in the south of Yunnan province, People's Republic of China. When the leaves are crushed, a characteristic smell of basmati rice or pandan leaves develops. Their hexane extract, prepared from a specimen growing in a greenhouse of the botanical garden of the Kunming Institute of Botany, contains 1-(3,4,5,6-tetrahydro-2-pyridyl)-1-propanone (41.2%) and 1-(1,4,5,6-tetrahydro-2-pyridyl)-1-propanone (37.5%) which constitute the main part of the volatile compounds. Minor components are 1-(3,4,5,6-tetrahydro-2-pyridyl)-1-ethanone (4.9%), 1-(1,4,5,6-tetrahydro-2-pyridyl)-1-ethanone (4.8%), 1-(2-piperidyl)-1-propanone (5.2%), 1-octen-3-ol (3.2%), 1-octen-3-one (1.9%), and 3-octanol and 1-(2-pyridyl)-1-propanone in trace amounts.
[structure: see text] Two novel triterpene dilactones with an unprecedented rearranged hexacyclic skeleton, kadlongilactones A (1) and B (2), have been isolated from the leaves and stems of Kadsura longipedunculata Finet et Gagnep (Schisandraceae). Their structures were established by comprehensive 1D and 2D NMR spectroscopic analysis, coupled with single-crystal X-ray crystallographic diffraction. Compounds 1 and 2 exerted significant inhibitory effects against human tumor K562 cells with IC(50) = 1.40 and 1.71 microg/mL, respectively.
Two new highly oxygenated nortriterpenoids with a unique norcycloartane skeleton, micrandilactones B and C, were isolated from Schisandra micrantha; micrandilactone C exhibited an EC50 value of 7.71 microg/mL (SI > 25.94) against HIV-1 replication with minimal cytotoxicity, and the potent anti-HIV-1 activity and unique structural features of make it a promising lead for therapeutic development of a new generation of anti-HIV drug.
[structure: see text]. Lancifodilactone G (1), a novel, highly oxygenated nortriterpenoid featuring a partial enol structure and a spirocyclic moiety, was isolated from the medicinal plant Schisandra lancifolia. Its structure and stereochemistry were determined from extensive one- and two-dimensional NMR and mass spectral data, coupled with single-crystal X-ray analysis. Compound 1 exerted minimal cytotoxicity against C8166 cells (CC50 > 200 microg/mL) and showed anti-HIV activity with EC50 = 95.47 +/- 14.19 microg/mL and a selectivity index in the range of 1.82-2.46.
Four new, highly oxygenated nortriterpenoids with unique schisanartane skeletons, micrandilactones D-G (1-4), have been isolated from the leaves and stems of Schisandra micrantha, and their structures have been elucidated on the basis of extensive spectral studies. The postulated biogenetic sequences of sixteen highly oxygenated nortriterpenoids and bisnortriterpenoids with new skeletons from three Schisandra species are discussed and have been compared from a chemotaxonomic standpoint.
The development of specific inhibitors that can block nuclear factor-kappaB (NF-kappaB) activation is an approach for the treatment of cancer, autoimmune, and inflammatory diseases. Several diterpenoids, oridonin, ponicidin, xindongnin A, and xindongnin B were isolated from the herb Isodon rubescens. These compounds were found to be potent inhibitors of NF-kappaB transcription activity and the expression of its downstream targets, cyclooxygenase-2 and inducible nitric-oxide synthase. The mechanisms of action of the diterpenoids against NF-kappaB are similar, but significant differences were also identified. All of the diterpenoids directly interfere with the DNA-binding activity of NF-kappaB to its response DNA sequence. Oridonin and ponicidin have an additional impact on the translocation of NF-kappaB from the cytoplasm to nuclei without affecting IkappaB-alpha phosphorylation and degradation. The effect of these compounds on the interaction of NF-kappaB with consensus DNA sequences is unique. Different inhibitory effects were observed when NF-kappaB bound to various DNA sequences. Both p65/p65 and p50/p50 homodimers, as well as p65/p50 heterodimer association with their responsive DNA, were inhibited. Kinetic studies on NF-kappaB-DNA interaction indicate that the diterpenoids decrease the B(max app) but have no effect on K(d app). This suggests that this class of compounds interacts with both p65 and p50 subunits at a site other than the DNA binding site and subsequently modulates the binding affinity of the transcription factor toward DNA with different NF-kappaB binding sequences. The diterpenoid structure could therefore serve as a scaffold for the development of more potent and selective NF-kappaB inhibitors that target regulated gene transcription.
[structures: see text] Lancifodilactone F (1), possessing an unprecedented rearranged pentanortriterpenoid backbone derived from cycloartane, was isolated from the leaves and stems of Schisandra lancifolia (Rehd. et Wils) A. C. Smith. Its structure was established by comprehensive NMR and MS spectroscopic analysis, coupled with single-crystal X-ray experiment. Compound 1 exerted minimal cytotoxicity against C8166 cells (CC50 > 200 microg/mL) and showed anti-HIV activity with EC50 = 20.69 +/- 3.31 microg/mL and a selectivity index > 6.62.
Investigation on the anthelminthic bioactive compounds of the ethanol extract of Tadehagi triquetrum resulted in the isolation of three new prenylated isoflavones, triquetrumones A (1), B (2), and C (3), and one new prenylated biisoflavanone, (R)-triquetrumone D (4), along with 16 known compounds, cyclokievitone (5), yukovanol (6), aromadendrin (7), kaempferol (8), astragalin (9), 2-O-methyl-l-chiro-inositol (10), galactitol (11), p-hydroxycinnamic acid (12), ursolic acid (13), betulinic acid (14), beta-sitosterol (15), daucosterol (16), stigmasterol (17), stigmasta-5,22-dien-3-O-beta-d-glucopyranoside (18), saccharose (19), and docosanoic acid (20). The structures of 1-4 were elucidated on the basis of spectroscopic and spectrometric methods. Compounds 1-3 displayed mild anthelminthic bioactivity, and compound 3 showed a significant binding ability to the estrogen receptor.
Two new taxoids, 2,20-O-diacetyltaxumairol N (1) and 14beta-hydroxy-10-deacetyl-2-O-debenzoylbacatin III (2), were isolated from the needles and stems of Taxus chinensis. Their structures were determined on the basis of extensive 1D- and 2D-NMR-spectral analysis. Compound 1 showed weak cytotoxicity activity against T-24 (IC50 = 34 microg/ml) and QGY-7701 (IC50 = 22 microg/ml) cancer lines. Compound 2 showed no obvious cytotoxicity activity against T-24 (IC50 > 100 microg/ml) and QGY-7701 (IC50 > 100 microg/ml) cancer lines.
Five new ent-kaurane diterpenoids, epi-maoecrystal N (1), eriocalyxin G (2), maoecrystal W (3), maoecrystal X (4), and maoecrystal Y (5), along with 22 known ones, were isolated from Isodon eriocalyx (Dunn.) Hara., and their structures were determined by spectroscopic methods. All diterpenoids, except for 3 and 13, were evaluated for inhibition of the K562, T-24, Me180, QGY-7701, and BIU87 cell lines (Table 2).
Nine new diterpenoids, albopilosins B-J (1-9), together with six known analogues, albopilosin A (10), macrocalyxin C (11), rabdokunmin C (12), excisanin (13), amethystonoic acid (14), and coetsanoic acid (15), were isolated from the aerial parts of Isodon albopilosus. The structures of 1-9 were established using spectroscopic methods including extensive 1D and 2D NMR analysis. The diterpenoids isolated were evaluated for their inhibitory activities against HepG2 (hepatoma) cells. Compounds 7 and 13 were the most active, with both having IC(50) values of <15 microM.
A new isoprenylated xanthone, cudrafrutixanthone A, was isolated from the roots of Cudrania fruticosa, together with 18 known compounds. Their structures were elucidated by spectroscopic methods. Most isoprenylated xanthones exhibited cytotoxicity against HCT-116, SMMC-7721, SGC-7901, and BGC-823 cell lines with IC (50) values of 1 - 5 microg/mL. Toxyloxanthone C and wighteone showed antifungal activity against Candida albicans with MICs of 25 and 12.5 microg/mL, respectively.
Five new oleanane-type triterpene saponins, named foenumosides A ( 1), B ( 2), C ( 3), D ( 4) and E ( 5), were isolated from the aerial parts of Lysimachia foenum-graecum Hance. Their structures were identified on the basis of 1D and 2D NMR techniques, including H-H COSY, HMQC, HMBC, HMQC-TOCSY, ROESY experiments as well as chemical methods. We have evaluated the cytotoxity of 1 - 5 against rat and human polymorphonuclear leukocytes and the effect of 5 on the arachidonic acid metabolizing enzyme. All compounds showed a high degree of toxicity except for compound 5, while 5 notably reduced the production of leukotriene B (4) (LTB (4)) from rat peritoneal leukocytes with an IC (50) value of 74 microM without inhibiting human elastase. Compound 5 also reduced the production of 12-HHTrE and 12-HETE by 14 % and 50 % as a measurement for cyclooxygenase-1 and 12-lipoxygenase inhibition at 100 microM.
Two new compounds, rubescensins Q and R (1 and 2), and a new acetonide derivative (3) of lasiodonin, together with thirteen known analogues, oridonin (4), ponicidin (5), wikstroemioidin B (6), lasiodonin (7), lasiokaurin (8), enmenol (9), 1-O-beta-D-glucopyranosyl-enmenol (10), trichokaurin (11), the acetonide of maoyecrystal F (12), rabdoternins A-D (13-16), have been isolated from Isodon rubescens var. taihangensis. The structures of the new compounds were elucidated on the basis of spectroscopic methods, especially the 2D NMR spectral analysis. Compound 3 exhibited cytotoxicity against K562, Bcap37, CA, CNE, BIU87, BGC823, and HeLa cell lines.