title: Meroditerpenoids from the brown alga Sargassum siliquastrum.
abstract: Eleven new meroditerpenoids (7-11, 14-17, 19, 20) and nine known compounds (1-6, 12, 13, 18) were isolated from the brown alga Sargassum siliquastrum. Combined chemical and spectroscopic analyses revealed a common tetraprenyl hydroquinone structure; these compounds belonged to the nahocol, isonahocol, and sargahydroquinoic acid classes. The dihydroquinone moiety of 20 was unique and unprecedented in a brown alga. Stereochemical assignments were made for several of the known compounds based on their chemical reactivity. These compounds exhibited moderate to significant radical-scavenging activity as well as weak inhibitory activities against sortase A and isocitrate lyase.
authors.affiliation: Natural Products Research Institute, College of Pharmacy, Seoul National University, San 56-1, Sillim, Gwanak, Seoul 151-742, Korea.
authors.forename: Misong
authors.initials: M
authors.lastname: Jung
authors.forename: Kyoung Hwa
authors.initials: KH
authors.lastname: Jang
authors.forename: Bora
authors.initials: B
authors.lastname: Kim
authors.forename: Bong Ho
authors.initials: BH
authors.lastname: Lee
authors.forename: Byoung Wook
authors.initials: BW
authors.lastname: Choi
authors.forename: Ki-Bong
authors.initials: KB
authors.lastname: Oh
authors.forename: Jongheon
authors.initials: J
authors.lastname: Shin
mesh_terms: D019881:Aminoacyltransferases / Q000037:antagonists & inhibitors; D001426:Bacterial Proteins / Q000037:antagonists & inhibitors; D001578:Benzopyrans / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D002176:Candida albicans / Q000201:enzymology; D003546:Cysteine Endopeptidases; D004224:Diterpenes / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology; D016166:Free Radical Scavengers / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology; D007522:Isocitrate Lyase / Q000037:antagonists & inhibitors; D007723:Korea; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D044647:Sargassum / Q000737:chemistry*; D013211:Staphylococcus aureus / Q000201:enzymology
chemical_list: D001426:Bacterial Proteins; D001578:Benzopyrans; D004224:Diterpenes; D016166:Free Radical Scavengers; D019881:Aminoacyltransferases; C120542:sortase A; D003546:Cysteine Endopeptidases; D007522:Isocitrate Lyase