title: High-yield total synthesis of (-)-strictinin through intramolecular coupling of gallates.
abstract: This paper describes a total synthesis of (-)-strictinin, an ellagitannin that is 1-O-galloyl-4,6-O-(S)-hexahydroxydiphenoyl (HHDP)-β-D-glucose. In the study, total efficiency of the synthesis was improved to produce a 78% overall yield in 13 steps from D-glucose. In the synthesis, formation of the 4,6-(S)-HHDP bridge including the 11-membered bislactone ring was a key step, in which intramolecular aryl-aryl coupling was adopted. The coupling was oxidatively induced by CuCl2-n-BuNH2 with perfect control of the axial chirality, and the reaction conditions of this coupling were optimized thoroughly to achieve the quantitative formation of the bridge.
authors.affiliation: School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda 669-1337, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Michihata
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kaneko
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Kasai
authors.forename: Kotaro
authors.initials: K
authors.lastname: Tanigawa
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Hirokane
authors.forename: Sho
authors.initials: S
authors.lastname: Higasa
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Yamada
mesh_terms: D060326:Chemistry Techniques, Synthetic; D005707:Gallic Acid / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010636:Phenols / Q000138:chemical synthesis* / Q000737:chemistry / Q000302:isolation & purification; D018515:Plant Leaves / Q000737:chemistry; D013237:Stereoisomerism; D064028:Tracheophyta / Q000737:chemistry
chemical_list: D010636:Phenols; C496786:strictinin; D005707:Gallic Acid