Yun-Sheng Lin

Frajunolides E-K, briarane diterpenes from Junceella fragilis.

Chemical investigation of the gorgonian octocoral Junceella fragilis, collected in Taiwan, resulted in the isolation of seven new briarane-type diterpenes, frajunolides E-K (1-7), in addition to 14 known briaranes, praelolide, junceellin, junceellolides A-E, and K, 11a,20a-epoxy-4-deacetoxyjunceelolide D, umbraculolide A, junceellonoid A, and juncins Y, Z, and ZI, as well as ergosterol peroxide. The structures of 1-7 were determined by analysis of HRESIMS and 2D NMR spectroscopic data. Cytotoxicity and in vitro anti-inflammatory activities of compounds 1-7 were also evaluated.

Bioactive Marine Prostanoids from Octocoral Clavularia viridis

Chemical investigation of the nonpolar extract of soft coral Clavularia viridis resulted in isolation of five new prostanoids, designated as claviridic acids A–E (1–5, resp.), in addition to the known clavulones I–III. Their structures were determined on the basis of spectroscopic techniques, especially HR‐ESI‐MS, CD, and 2D‐NMR experiments. The isolated marine prostanoids exhibited potent inhibitory effect on PHA‐induced proliferation of peripheral blood mononuclear cells (PBMC), as well as significant cytotoxic activity against human gastric cancer cells (AGS).

The structure of δ-cadinol—amorphan-3-ene-9β-ol

Abstract The structure of δ-cadinol was established as amorphan-3-ene-9β-ol (VIII) by chemical behavior and spectroscopic data.

Four New Briarane Diterpenoids from Taiwanese Gorgonian Junceella fragilis

Four new 8-hydroxybriarane diterpenoids, frajunolides P–S (1–4), together with umbraculolide A, juncenolide C, junceellonoid A and juncin R, were isolated from the acetone extract of the gorgonian Junceella fragilis, collected from the southeast coast of Taiwan. Compound 1 contains an unusual pivaloyloxy group at C-2, while 3 is a rare compound having a chlorine atom on the olefinic carbon (C-6). The structures of the isolated compounds were established by extensive spectroscopic analysis, including 1D- and 2D-NMR, as well as HRMS data. Compound 1 was further confirmed by X-ray crystallographic analysis. In the anti-inflammatory test, compounds 1 and 2 exhibited moderate inhibition on superoxide anion generation and elastase release by human neutrophils in response to formylmethionylleucyl-phenylalanine/dihydrocytochalasin B (fMLP/CB).

The structure of 4-ketocedrol

4-Ketocedrol was isolated fromn-hexane extraction ofJuniperus squamata Linn. and its formula established by physical and chemical evidence.

Frajunolides L–O, Four New 8-Hydroxybriarane Diterpenoids from the Gorgonian Junceella fragilis

Four new 8-hydroxybriarane diterpenoids, frajunolides L–O (1–4), were isolated from the Taiwanese gorgonian Junceella fragilis. The structures of compounds 1–4 were elucidated based on spectroscopic analysis, especially 2D NMR (1H-1H COSY, HSQC, HMBC and NOESY) and HRMS. Compounds 1 and 4 showed weak anti-inflammatory activity as tested by superoxide anion generation and elastase release by human neutrophil in response to fMLP/CB. Compound 3 showed selective inhibition on elastase release in vitro.

The structure of isocedrolic acid isolated fromJuniperus squamata Lamb

Isocedrolic acid isolated fromJuniperus squamata Lamb. was established as 8s-hydroxycedrane-12-carboxylic acid by chemical and physical evidence.

New Briarane Diterpenoids from Taiwanese Soft Coral Briareum violacea

Ten new briarane diterpenoids, briaviolides A–J (1–10), together with six known briaranes, solenolides A and D, excavatolide A, briaexcavatolide I, 4β-acetoxy-9-deacetystylatulide lactone and 9-deacetylstylatulide lactone, were isolated from the Taiwanese soft coral, Briareum violacea. Their structures were determined on the basis of spectroscopic data (1H- and 13C-NMR, 1H–1H COSY, HSQC, HMBC and NOESY), HR-MS and chemical methods. The absolute configuration of briaviolide A (1) was determined by X-ray crystallographic analysis. Compounds 5, 9 and derivative 11 showed moderate inhibitory activities on superoxide-anion generation and elastase release by human neutrophils in response to N-formyl-methionyl-leucyl-phenylalanine/Cytochalasin B (fMLP/CB).

Extractive components from the nutmeg ofMyristica simarum A. DC.: The structure of lignan-ketone: Otobanone

Otobanon obtained fromn-hexane extract ofMyristica simarum A. DC. was elucidated as 1-oxo-otobain by the physical spectra and chemical degradation.

New Cytotoxic Prostanoids from Taiwanese Soft Coral Clavularia viridis

Chemical investigation of the AcOEt/MeOH extract of Clavularia viridis collected in Taiwan has afforded four new prostanoids, named claviridins A–D (1–4, resp.). The structures of compounds 1–4 were determined on the basis of 1D‐ and 2D‐NMR techniques, including COSY, HMQC, HMBC, and NOESY experiments. Pharmacological studies revealed that compounds 1–4 exhibited potent cytotoxicity against human cancer cells.