Yan-Hui Fu

Bioactive Anthraquinone Derivatives from the Mangrove-Derived Fungus Stemphylium sp. 33231

Four new anthraquinone derivatives (1-4) and four new alterporriol-type anthranoid dimers (14-17), along with 17 analogues, were isolated from the solid rice fermentation of the fungus Stemphylium sp. 33231 obtained from the mangrove Bruguiera sexangula var. rhynchopetala collected from the South China Sea. Their structures were elucidated using comprehensive spectroscopic methods. The absolute configurations of 1, 3, and 4 were determined by single-crystal X-ray diffraction of their derivatives (1a, 3b, and 4a). The absolute configurations of the chiral 17-19 were determined by comparing their CD spectra with 21. The inhibitory activities of most of the compounds against seven terrestrial pathogenic bacteria and two cancer cell lines were evaluated.

New clerodane diterpenoids from the roots of Polyalthia laui.

Five new clerodane diterpenoids, polylauiester A (1), (4→2)-abeo-2,13-diformyl-cleroda-2,12E-dien-14-oic acid (2) and polylauiamides B-D (3-5), together with 11 known clerodane diterpenoids (6-16), were isolated from the roots of Polyalthia laui. Among them, polylauiester A (1) represents the first example of a novel norclerodane diterpenoid only containing 17 carbon atoms on the carbon skeleton, and polylauiamide B (3) is an unusual diterpenoid with a p-substituted benzene ring as a substituent. Their structures were elucidated by extensive spectroscopic methods, and the relative configuration of polylauiamide B (3) was further confirmed by the single crystal X-ray diffraction method. Biological evaluation of new compounds against human Hela, MCF-7 and A549 human cancer cell lines showed that all compounds displayed weak cytotoxicities against various human cancer cell lines in the range of IC50 at 25.01-39.31μM.

Four new tetracyclic alkaloids with cis-decahydroquinoline motif from Myrioneuron effusum.

Four new Myrioneuron alkaloids, mysumamides A-D (1-4), along with three known ones were isolated from the twigs and leaves of Myrioneuron effusum. All of these alkaloids possessed the tetracyclic skeleton and contained the decahydroquinoline (cis-DHQ) moiety. Their structures and relative configurations were elucidated on the basis of spectroscopic methods, especially 2D NMR techniques. The absolute configuration of 1 was determined by single-crystal X-ray diffraction. The cytotoxic activities of these compounds were also evaluated in vitro.

A new isoflavone from the roots of Ficus auriculata

Abstract A new isoflavone, 5,7,4′-trihydroxy-3′-hydroxymethylisoflavone (1), together with three known isoflavones, 3′-formyl-5,4′-dihydroxy-7-methoxyisoflavone (2), ficuisoflavone (3) and alpinumisoflavone (4), were isolated from the roots of Ficus auriculata. Among them, 1 is a rare isoflavone containing 16 carbon atoms on the carbon skeleton. The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with data reported in the literature. All compounds were evaluated for their antibacterial activities against five terrestrial pathogenic bacteria in vitro. Compounds 1–4 showed significant antibacterial activities against various terrestrial pathogenic bacteria with MIC values ranging from 1.30 to 39.93 μM.

Bioactive furanocoumarins from the stems and leaves of Clausena hainanensis

Abstract A new furanocoumarin, clauhainanin A (1), together with seven known furanocoumarins (2–8), were isolated from the stems and leaves of Clausena hainanensis. The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with data reported in the literature. All known compounds (2–8) were isolated from C. hainanensis for the first time. All isolated compounds were evaluated for their cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Compounds 1–8 exhibited significant inhibitory effects with IC50 values ranging from 1.36 to 18.96 μM.

A new dihydrochalcone glycoside from the stems of Homalium stenophyllum

Abstract A new dihydrochalcone glycoside, phloretin-4-O-β-D-glucopyranoside (1), together with seven known flavonoids (2–8), were isolated from the stems of Homalium stenophyllum. The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with data reported in the literature. The known compounds (2–8) were isolated from the genus Homalium for the first time. All compounds were evaluated for their antibacterial activities against six pathogenic bacteria in vitro.

Bioactive Phenolic and Isocoumarin Glycosides from the Stems of Homalium paniculiflorum

Two new phenolic glycosides (1 and 2) and two new isocoumarin glycosides (3 and 4), along with 14 known compounds (5–18), were isolated from the stems of Homalium paniculiflorum. Their structures were established on the basis of extensive spectroscopic analyses and chemical methods. All new compounds were evaluated for their anti-inflammatory activities via examining the inhibitory activity on nitric oxide (NO) production induced by lipopolysaccharide (LPS) in mouse macrophage RAW 264.7 cells in vitro. Compounds 1 and 4 exhibited inhibitory activities with IC50 values of 30.23 ± 1.23 μM and 19.36 ± 0.19 μM, respectively.

Bioactive monoterpene indole alkaloids from Nauclea officinalis

Two new monoterpene indole alkaloids, naucleaoffines A (1) and B (2), together with six known alkaloids (3-8), were isolated from the stems and leaves of Nauclea officinalis. The structures of 1 and 2 were elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with the data reported in literature. All isolated compounds were evaluated for their anti-inflammatory activities and anti-HIV-1 activities. Compounds 1-8 exhibited significant inhibitory activities on nitric oxide (NO) production induced by lipopolysaccharide in mouse macrophage RAW 264.7 cells in vitro with IC50 values comparable to that of hydrocortisone. In addition, compounds 1-8 showed significant anti-HIV-1 activities with EC50 ranged from 0.06 to 2.08u202fµM. These findings suggest that the discoveries of these indole alkaloids with significant anti-inflammatory activities and anti-HIV-1 activities isolated from N. officinalis could be of great importance to the development of new anti-inflammatory and anti-HIV agents.

Structurally diverse diterpenoids from Trigonostemon howii

Abstract Phytochemical investigation on the stems and leaves of Trigonostemon howii resulted in the isolation of a new abietane diterpenoid, trigohowimine A (1), along with seven known structurally diverse diterpenoids (2–8). The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparison with data reported in the literature. New compound 1 was evaluated for its cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480. Compound 1 showed significant inhibitory effects against various human cancer cell lines with IC50 values ranging from 0.82 to 8.53 μM.

Biologically active oligostilbenes from the stems of Vatica mangachapoi and chemotaxonomic significance

Abstract Phytochemical investigation of the stems of Vatica mangachapoi (Dipterocarpaceae) led to the isolation and structural elucidation of twenty-seven oligostilbenes (1–27), including a new natural compound 1. The structure of 1 was elucidated on the basis of spectroscopic analyses including NMR, MS and ECD data, and the known compounds were identified by comparisons with those reported in the literature. The absolute configuration of 1 was first time determined by a combination of NOESY spectrum and quantum chemical computation. Among of isolates were tested for their anti-osteoporosis and anti-HIV-1 activities in vitro by the MTT method. Moreover, the chemotaxonomic significance of these compounds was summarised.