Cytotoxic hydroazulene diterpenes from the brown alga Dictyota dichotoma.
Two new hydroazulenoid (prenyl guaiane) diterpenes, dictyone acetate (2) and 3,4-epoxy 13-hydroxy pachydictyol A (4) were isolated from the petroleum ether fraction of the alcoholic extract of the brown alga, Dictyota dichotoma (Hudson) Lamouroux, which was collected from the Red Sea coasts at Hurgada, Egypt, together with three known ones, pachydictyol A (1), dictyone (3) and 11-hydroxypachydictyol A (dictyol E) (5). In addition, the steroidal compound, stigmasta-5,(E)-24(28)-dien-3-beta-ol (fucosterol) (6) was also isolated. The structures of the isolated compounds have been determined on the basis of spectroscopic evidences as well as physical and chemical correlation with known compounds. Compounds 1, 2, 3 and 5 showed moderate cytotoxic activity.
Gedara
Sahar R
SR
Department of Pharmacognosy, Faculty of Pharmacy, Mansoura University, Mansoura 35516, Egypt.
Abdel-Halim
Osama B
OB
el-Sharkawy
Saleh H
SH
Salama
Osama M
OM
Shier
Thomas W
TW
Halim
Ahmed F
AF
D016475:3T3 Cells; D000473:Alkanes; D000818:Animals; D002470:Cell Survival / Q000187:drug effects*; D002472:Cell Transformation, Viral; D003603:Cytotoxins / Q000737:chemistry* / Q000302:isolation & purification; D004224:Diterpenes / Q000737:chemistry* / Q000302:isolation & purification / Q000633:toxicity*; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D008958:Models, Molecular; D008968:Molecular Conformation; D015394:Molecular Structure; D010578:Petroleum; D000459:Phaeophyceae / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification; D012623:Seawater
D000473:Alkanes; D003603:Cytotoxins; D004224:Diterpenes; D010578:Petroleum; D010936:Plant Extracts; C004544:naphtha