title: Absolute stereochemistry of altersolanol A and alterporriols.
abstract: The absolute stereochemistry of altersolanol A (1) was established by observing a positive exciton couplet in the circular dichroism (CD) spectrum of the C3,C4-O-bis(2-naphthoyl) derivative 10 and by chemical correlations with known compound 8. Before the discussion, the relative stereochemistry of 1 was confirmed by X-ray crystallographic analysis. The shielding effect at C7'-OMe group by C1-O-benzoylation established the relative stereochemical relationship between the C8-C8' axial bonding and the C1-C4/C1'-C4' polyol moieties of alterporriols E (3), an atropisomer of the C8-C8' dimer of 1. As 3 could be obtained by dimerization of 1 in vitro, the absolute configuration of its central chirality elements (C1-C4) must be identical to those of 1. Spectral comparison between the experimental and theoretical CD spectra supported the above conclusion. Axial stereochemistry of novel C4-O-deoxy dimeric derivatives, alterporriols F (4) and G (5), were also revealed by comparison of their CD spectra to those of 2 and 3.
authors.affiliation: Department of Biochemistry and Biotechnology, Faculty of Agriculture and Life Science, Hirosaki University, Hirosaki 036-8561, Japan.
authors.forename: Saki
authors.initials: S
authors.lastname: Kanamaru
authors.forename: Miho
authors.initials: M
authors.lastname: Honma
authors.forename: Takanori
authors.initials: T
authors.lastname: Murakami
authors.forename: Taro
authors.initials: T
authors.lastname: Tsushima
authors.forename: Shinji
authors.initials: S
authors.lastname: Kudo
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Tanaka
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Nihei
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Nehira
authors.forename: Masaru
authors.initials: M
authors.lastname: Hashimoto
mesh_terms: D000880:Anthraquinones / Q000737:chemistry*; D002942:Circular Dichroism; D019281:Dimerization; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010860:Pigments, Biological / Q000737:chemistry; D004718:Saccharomycetales / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000880:Anthraquinones; D010860:Pigments, Biological; C574404:alteporriol F; C574405:alteporriol G; C064250:alterporriol D; C064252:alterporriol E; C058812:altersolanol A