title: Cembrane diterpenes from the southern African soft coral Cladiella kashmani.
abstract: Two known cembrane diterpenes, flaccidoxide (1) and (1Z,3E,7E,11S, 12S,14S)-11,12-epoxy cembra-1,3,7-trien-14-ol (2), and the new cembrane diterpene flaccidoxide-13-acetate (3) were isolated from specimens of Cladiella kashmani collected off Ponto do Oura, Mozambique. The modified Mosher's method established the previously unassigned absolute configuration of 1 as (1Z,3E,7E,11S,12S,13S, 14R)-14-acetoxy-11,12-epoxy cembra-1,3,7-trien-13-ol. Acetylation of 1 yielded 3 and thus confirmed the structure of 3 as (1Z,3E,7E,11S, 12R,13S,14R)-13,14-diacetoxy-11,12-epoxy cembra-1,3,7-triene. All three diterpenes were toxic to the brine shrimp Artemia salina.
authors.affiliation: Department of Chemistry, Rhodes University, Grahamstown, 6140, South Africa.
authors.forename: C A
authors.initials: CA
authors.lastname: Gray
authors.forename: M T
authors.initials: MT
authors.lastname: Davies-Coleman
authors.forename: M H
authors.initials: MH
authors.lastname: Schleyer
mesh_terms: D000107:Acetylation; D000818:Animals; D000970:Antineoplastic Agents / Q000302:isolation & purification* / Q000494:pharmacology; D003063:Cnidaria / Q000737:chemistry*; D004224:Diterpenes / Q000302:isolation & purification* / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D013019:South Africa; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; D004224:Diterpenes; C420264:flaccidoxide; C420263:flaccidoxide-13-acetate