title: Total synthesis of 10-isocyano-4-cadinene and its stereoisomers and evaluations of antifouling activities.
abstract: The first enantioselective total synthesis of 10-isocyano-4-cadinene, a marine sesquiterpene isolated from nudibranchs of the family Phyllidiidae, and determination of its absolute stereochemistry were achieved. 10-Isocyano-4-cadinene is expected to be a novel nontoxic antifouling agent. In the synthesis, intermolecular Diels-Alder reaction and samarium diiodide induced Barbier-type cyclization were employed as key steps. The absolute configuration of 10-isocyano-4-cadinene was determined as (1S,6S,7R,10S) by comparison of the optical rotations between natural and synthetic samples. In addition, the authors successfully synthesized 10-epi- and di-1,6-epi-10-isocyano-4-cadinene through the same synthetic pathway. Antifouling activities against Balanus amphitrite with the cadinenes were also evaluated.
authors.affiliation: Division of Environmental Materials Science, Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Nishikawa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nakahara
authors.forename: Yousuke
authors.initials: Y
authors.lastname: Shirokura
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Nogata
authors.forename: Erina
authors.initials: E
authors.lastname: Yoshimura
authors.forename: Taiki
authors.initials: T
authors.lastname: Umezawa
authors.forename: Tatsufumi
authors.initials: T
authors.lastname: Okino
authors.forename: Fuyuhiko
authors.initials: F
authors.lastname: Matsuda
mesh_terms: D000818:Animals; D003486:Cyanides / Q000138:chemical synthesis* / Q000737:chemistry* / Q000494:pharmacology; D003500:Cyclization; D009682:Magnetic Resonance Spectroscopy; D009281:Naphthalenes / Q000138:chemical synthesis* / Q000737:chemistry* / Q000494:pharmacology; D009904:Optical Rotation; D000081223:Polycyclic Sesquiterpenes; D012717:Sesquiterpenes / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D013237:Stereoisomerism; D001468:Thoracica / Q000187:drug effects
chemical_list: C480379:10-isocyano-4-cadinene; D003486:Cyanides; D009281:Naphthalenes; D000081223:Polycyclic Sesquiterpenes; D012717:Sesquiterpenes