Five new 2-(2-phenylethyl)chromone derivatives from agarwood.

Agarwood has been used as an incense and in traditional medicines as aphrodisiac, sedative, cardiotonic, and carminative. In this study, five new 2-(2-phenylethyl)chromones (2, 13-16) and eleven known compounds (1, 3-12) were isolated from the agarwood. The structures of the new compounds were determined by H-, C-, and two-dimensional NMR together with electronic circular dichroism (ECD) spectroscopy.

Three new 5,6,7,8-tetrahydroxy-5,6,7,8-tetrahydrochromone derivatives enantiomeric to agarotetrol from agarwood.

Agarwood (jinkoh in Japanese) is a resinous wood from Aquilaria species of the family Thymelaeaceae and has been used as incense and in traditional medicines. Characteristic chromone derivatives such as agarotetrol have been isolated from agarwood. In previous study, we isolated two new 2-(2-phenylethyl)chromones together with six known compounds from MeOH extract of agarwood.

Effects of saffron and its constituents, crocin-1, crocin-2, and crocetin on α-synuclein fibrils.

Saffron, the stigma of Crocus sativus Linné (Iridaceae family), has been known to inhibit aggregation of β-amyloid, a nerve tissue protein. α-Synuclein (αS) is a 140-amino acid protein found abundantly in various regions of the brain. Its abnormal aggregation and accumulation in nerve tissue are said to cause neurodegenerative diseases such as Parkinson's disease, Lewy body dementia, and multiple-system atrophy.

Agarwood Inhibits Histamine Release from Rat Mast Cells and Reduces Scratching Behavior in Mice: Effect of Agarwood on Histamine Release and Scratching Behavior.

Objectives: This study was conducted to clarify the effects of agarwood on histamine release from mast cells in rats and on the scratching behaviors in mice.

Methods: Histamine release from rat mast cells induced by compound 48/80 or concanavalin A (Con A) and compound 48/80-induced scratching behavior in mice were examined to investigate the effects of agarwood. The hyaluronidase activity and the 3',5'-cyclic adenosine monophosphate (cAMP) levels in mast cells were examined to investigate the mechanisms for the inhibition of histamine release.

New 2-(2-Phenylethyl)chromone Derivatives and Inhibitors of Phosphodiesterase (PDE) 3A from Agarwood.

The MeOH extract of agarwood showed inhibitory activity against phosphodiesterase (PDE) 3A. Fractionation of the extract led to the isolation of two new 2-(2-phenylethyl)chromones, 6,8-dihydroxy-2-[2-(4'-methoxyphenyl)ethyl]chromone (6), and 6,7-dihydroxy-2-(2-phenylethyl)chromone (8), together with six known compounds. All isolated compounds were tested for their PDE 3A inhibitory activity using fluorescence polarization method.

Analgesic Effects of Toad Cake and Toad-cake-containing Herbal Drugs: Analgesic effects of toad cake.

Objectives: This study was conducted to clarify the analgesic effect of toad cake and toad-cake-containing herbal drugs.

Methods: We counted the writhing response of mice after the intraperitoneal administration of acetic acid as a nociceptive pain model and the withdrawal response after the plantar surface stimulation of the hind paw induced by partial sciatic nerve ligation of the mice as a neuropathic pain model to investigate the analgesic effect of toad cake and toad-cake-containing herbal drugs. A co-treatment study with serotonin biosynthesis inhibitory drug 4-chloro- DL-phenylalanine methyl ester hydrochloride (PCPA), the catecholamine biosynthesis inhibitory drug α-methyl- DL-tyrosine methyl ester hydrochloride (AMPT) or the opioid receptor antagonist naloxone hydrochloride was also conducted.

Synthesis and biological activities of glycosphingolipid analogues from marine sponge Aplysinella rhax.

A novel glycosphingolipid, beta-D-GalNAcp(1-->4)[alpha-D- Fucp(1-->3)]-beta-D-GlcNAcp(1-->)Cer (1), isolated from the marine sponge Aplysinella rhax, has a unique structure, with D-fucose and N-acetyl-D-galactosamine attached to a reducing-end N-acetyl-D-glucosamine through an alpha1-->3 and beta1-->4 linkage, respectively. We synthesized glycolipid analogues carrying a 2-branched fatty alkyl residue or a 2-trimethylsilyl ethyl residue in place of ceramide (2 and 3), non-natural type trisaccharide analogue containing an L-fucose residue (4), and other analogues (5 and 6). Among these prepared compounds, 2 showed the most potent nitric oxide (NO) production inhibitory activity against LPS-activated J774.