Isolation of linobiflavonoid, a novel biflavonoid from Linostoma pauciflorum Griff

A novel biflavonoid, that we have named linobiflavonoid, and the known biscoumarin ether, daphnoretin, were isolated from the root extracts of Linostoma pauciflorum Griff. The structure of linobiflavonoid was determined from interpretation of its NMR spectroscopic data and from a comparison of this data with those of known biflavonoids and biflavones. The known flavones, 5,4\u27-dihydroxy- 7,3\u27,5\u27-trimethoxyflavone and 5,4\u27-dihydroxy-7-methoxyflavone along with stigmasterol were isolated from the vines of the same plant. 4\u27-Dihydroxy-7,3\u27-5\u27-trimethoxyflavone was active against Mycobacterium tuberculosis (MIC 3.13 mu M) and KB-oral cavity cancer (IC50 17.41 mu M). (C) 2011 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved

8-O-Acetyl-8-epi-9-de­oxygoniopypyrone

The title compound (systematic name: 7-oxo-3-phenyl-2,6-dioxabicyclo­[3.3.1]nonan-4-yl acetate), C15H16O5, is a styryllactone derivative which was isolated from Goniothalamus macrophyllus. The mol­ecule has two fused rings consisting of a tetra­hydro-2H-pyran and a lactone ring, with the benzene ring and the acetyl group attached to the tetra­hydro-2H-pyran ring. The tetra­hydro-2H-pyran ring is in a standard chair conformation, whereas the lactone ring is in an envelope conformation. In the crystal, mol­ecules are linked by weak C—H⋯O inter­actions into sheets parallel to the ac plane. Weak C—H⋯π inter­actions are also observed

A new cerebroside and the cytotoxic constituents isolated from <i>Xylaria allantoidea</i> SWUF76

<p>A new cerebroside, namely allantoside (<b>1</b>), and 10 known compounds (<b>2</b>–<b>11</b>) were isolated from <i>Xylaria allantoidea</i> SWUF76. The structure of compound <b>1</b> was determined by comprehensive spectroscopic analysis including 1D and 2D nuclear magnetic resonance (NMR) as well as high-resolution electron ionisation mass spectrometry (HREIMS) and electrospray ionisation mass spectrometry (ESIMS). Compounds <b>1</b>, <b>4</b>, <b>5</b>, <b>6</b>, <b>7</b>, <b>8</b> and <b>11</b> were evaluated for cytotoxic activities against cancer cell lines (Hela, HT29, HCT116 and MCF-7) and normal Vero cell lines by MTT assay. Compounds <b>6</b> and <b>7</b> exhibited anticancer activity after 24 h of treatment. Compound <b>7</b> showed significant cytotoxicity against Hela (IC₅₀ = 2.24 μg/mL), HT29 (IC₅₀ = 2.51 μg/mL), HCT116 (IC₅₀ = 3.50 μg/mL) and MCF-7 (IC₅₀ = 3.77 μg/mL) and Vero (IC₅₀:3.65 μg/mL) cells. Compound <b>6</b> showed slight cytotoxicity against all tested cancer cell lines.</p

Rearranged Benzophenones and Prenylated Xanthones from <i>Garcinia propinqua</i> Twigs

The first phytochemical investigation of <i>Garcinia propinqua</i> has led to the isolation and identification of three new compounds, including two rearranged benzophenones, doitunggarcinones A (<b>1</b>) and B (<b>2</b>), and a xanthone, doitunggarcinone C (<b>3</b>), together with seven known compounds (<b>4</b>–<b>10</b>). The structures of <b>1</b>–<b>3</b> were elucidated on the basis of spectroscopic methods, including UV, IR, NMR, and MS. The antibacterial activity of the 10 isolates was evaluated against <i>Escherichia coli</i> TISTR 780, <i>Salmonella typhimurium</i> TISTR 292, <i>Staphylococcus aureus</i> TISTR 1466, and methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) SK1

Isolation of linobiflavonoid, a novel biflavonoid from Linostoma pauciflorum Griff.

A novel biflavonoid, that we have named linobiflavonoid, and the known biscoumarin ether, daphnoretin, were isolated from the root extracts of Linostoma pauciflorum Griff. The structure of linobiflavonoid was determined from interpretation of its NMR spectroscopic data and from a comparison of this data with those of known biflavonoids and biflavones. The known flavones, 5,4\u27-dihydroxy- 7,3\u27,5\u27-trimethoxyflavone and 5,4\u27-dihydroxy-7-methoxyflavone along with stigmasterol were isolated from the vines of the same plant. 4\u27-Dihydroxy-7,3\u27-5\u27-trimethoxyflavone was active against Mycobacterium tuberculosis (MIC 3.13 mu M) and KB-oral cavity cancer (IC50 17.41 mu M). (C) 2011 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved