| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 5176658 | Phytochemistry Letters | 2015 | 4 Pages |
â¢Three new compounds (1-3) were isolated from an extract of watermelon seeds.â¢1 and 2 were compounds with pyrrole and pyrazole rings in a molecule.â¢1-3 were evaluated for melanogenesis inhibitory activities.â¢1 exhibited modest inhibitory activity (inferior to arbutin) without cytotoxicity.
Three new compounds, i.e. 1-[2-(5-hydroxymethyl-1H-pyrrole-2-carbaldehyde-1-yl)ethyl]-1H-pyrazole (1), 1-({[5-(α-d-galactopyranosyloxy)methyl]-1H-pyrrole-2-carbaldehyde-1-yl}-ethyl)-1H-pyrazole (2), and (4-hydroxyphenyl)methanol 4-[β-d-apiofuranosyl(1â2)-O-β-d-glucopyranoside] (3), were isolated from an extract of watermelon seeds. Compounds 1 and 2 were pyrazole-alkaloids with a pyrrole ring. This is the first study to show compounds with pyrrole and pyrazole rings in a molecule isolated from natural products. In the evaluation for melanogenesis inhibitory, compound 1 exhibited modest inhibitory activity on melanogenesis without cytotoxicity. Meanwhile compound 2 showed some inhibitory activity accompanied by some cytotoxicity.
Graphical abstractDownload full-size image
