title: Total synthesis of (R)-telomestatin.
abstract: We have achieved a total synthesis of telomestatin, and its absolute configuration was determined to be (R). Coupling of cysteine-containing trisoxazole amine and serine-containing trisoxazole carboxylic acid, followed by macrocyclization, provided a 24-membered diamide. The seventh oxazole ring was formed by a Shin's procedure via dehydroamide. Cyclodehydration of a modified (R)-cysteine-(S-(t)Bu) moiety using Kelly's method (PPh3(O)-Tf2O) with anisole furnished (R)-telomestatin, whose CD spectrum was in good agreement with that of the natural product.
authors.affiliation: Department of Applied Chemistry, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo 152-8552, Japan. doit@apc.titech.ac.jp
authors.forename: Takayuki
authors.initials: T
authors.lastname: Doi
authors.forename: Masahito
authors.initials: M
authors.lastname: Yoshida
authors.forename: Kazuo
authors.initials: K
authors.lastname: Shin-ya
authors.forename: Takashi
authors.initials: T
authors.lastname: Takahashi
mesh_terms: D015394:Molecular Structure; D010080:Oxazoles / Q000138:chemical synthesis*; D013302:Streptomyces / Q000737:chemistry; D019098:Telomerase / Q000037:antagonists & inhibitors
chemical_list: D010080:Oxazoles; C431888:telomestatin; D019098:Telomerase