Dan-Yi Li

Caryophyllene Sesquiterpenes from the Marine-Derived Fungus Ascotricha sp. ZJ-M-5 by the One Strain–Many Compounds Strategy

The marine-derived fungus Ascotricha sp. ZJ-M-5, which can produce cyclonerodiol analogues, a 3,4-seco lanostane triterpenoid, and diketopiperazines in an eutrophic medium, was subjected to a one strain-many compounds (OSMAC) analysis. It was found to produce three new caryophyllene derivatives (1-3) and the known 1,3,6-trihydroxy-8-methylxanthone (4) in an oligotrophic medium, Czapek Dox broth with or without Mg(2+). (+)-6-O-Demethylpestalotiopsin A (1) and (+)-6-O-demethylpestalotiopsin C (2), which have a five-membered hemiacetal structural moiety, showed growth inhibitory effects against HL-60 and K562 leukemia cell lines with the lowest GI50 value of 6.9 ± 0.4 μM. It can be concluded that modification of the culture media is still effective in the discovery of novel bioactive fungal secondary metabolites.

Three new diterpenoids from the resin of Liquidambar formosana

Three new diterpenoids, liquidambolide A (1) and liquiditerpenoic acids A (2) and B (3), together with 10 known diterpenes were isolated from the resin of Liquidambar formosana Hance, whose structures were elucidated by detailed analysis on the NMR and HR-ESI-MS spectra.

Triterpenoid prosapogenols and prosapogenins from the husks of Xanthoceras sorbifolia.

Two new prosapogenins, 16-O-acetyl-21-O-(4-angeloyl)-α-l-rhamnopyranosyl barringtogenol C (1), 28-O-β-d-glucopyranosyl 16-deoxybarringtogenol C (2), were isolated from the acid hydrolyzate of the crude saponin obtained from the husks of Xanthoceras sorbifolia Bunge, along with six known triterpenoids. These structures were established on the basis of chemical and detailed spectral evidences. Compounds 1 and 2 showed cytotoxic activity against human cell lines (A375-S2, HeLa).

Three new acylated flavone C-glycosides from the flowers of Trollius chinensis

Three new flavone C-glycosides with the substitution of the unusual acyl, 2″-O-veratroylisoswertisin (1), 3″-O-2-methylbutyrylisoswertiajaponin (2), and 3″-O-2-methylbutyrylvitexin (3), together with the known compounds of 2″-O-2-methylbutyrylisoswertisin (4), 3″-O-2-methylbutyrylisoswertisin (5), and trollisin I (6) were isolated from the antibacterial fraction of the aqueous extract of the flowers of Trollius chinensis. The structural elucidations of these compounds were carried out by a detailed analysis of the NMR and MS spectra.

A new cyclonerol derivative from a marine-derived fungus Ascotricha sp. ZJ-M-5

A new sesquiterpene, ascotrichic acid (1), was isolated from a marine-derived fungus Ascotricha sp., together with the other two known analogues, cyclonerodiol (2) and 10(Z)-cyclonerotriol (3). Its structure was established by spectroscopic methods (1D and 2D NMR, HR-ESI-MS).

Two new compounds from a marine-derived fungus Penicilliumoxalicum

Two new anthraquinones, emodin-3-O-sulphate (1) and citreorosein-3-O-sulphate (2), as well as five known anthraquinones, were isolated from a marine-derived fungus Penicillium oxalicum. The structures of these compounds were determined by spectroscopic methods (1D and 2D NMR, HR-ESI-MS).

Antimicrobial constituents from the flowers of Trollius chinensis

A new 1-aryl-isochroman, trolliusol A (1), was isolated from the flowers of Trollius chinensis, along with seven known phenolic compounds in an antimicrobial activity-directed phytochemical investigation. The structures of these compounds were elucidated by spectroscopic methods, and their inhibitory activities against one fungus and four bacterial strains were measured.

Two new triterpenoid saponins from the husks of Xanthoceras sorbifolia

Two new oleanane triterpenoid saponins, xanthohuskisides A (1) and B (2), were isolated from the husks of Xanthoceras sorbifolia. The structures of these two compounds were established as 3-O-β-D-glucopyranosyl (1→6)-[β-D-glucopyranosyl (1→2)]-β-D-glucopyranosyl, 28-O-β-D-glucopyranosyl (1→6)-[α-L-rhamnopyranosyl (1→2)]-β-D-glucopyranosyl 16-deoxybarringtogenol C (1) and 3-O-β-D-glucopyranosyl (1→6)-[β-D-glucopyranosyl (1→2)]-β-D-glucopyranosyl, 28-O-β-D-glucopyranosyl (1→6)-β-D-glucopyranosyl 16-deoxybarringtogenol C (2), respectively, based on the analysis on their spectral data including NMR and HR-ESI-MS. The growth inhibitory activities of compounds 1 and 2 were assayed, and 2 showed moderate activity against U937 cell line with the IG50 value of 82.85 ± 1.58 µM.

A novel prenylated xanthone from the stems and leaves of Calophyllum inophyllum.

A novel prenylated xanthone, caloxanthone Q (1), was isolated from the stems and leaves of Calophyllum inophyllum. The structure elucidation was carried out by detailed spectroscopic analysis.

Two new threitol orsellinates from a sea mud-derived fungus, Ascotricha sp. ZJ-M-5

Abstract Two new d-threitol orsellinates (1–2) were isolated from the EtOAc extract of a sea mud-derived fungus, Ascotricha sp. ZJ-M-5, cultured in Czapek Dox broth. These two compounds featured in the symmetrical substitution of orsellinic acid or acetic acid, which was established on the basis of 1D and 2D NMR experiments. The characteristic optical rotations enabled the assignment of the absolute configuration.