title: Evidence for pi-stacking as a source of stereocontrol in the synthesis of the core pyranochromene ring system common to calyxin I, calyxin J, and epicalyxin J.
abstract: A diastereoselective synthesis of the tetrahydropyranochromene ring system common to several natural product isolates of Alpinia blepharocalyx is reported. We have shown that a stereochemical preference exists for a syn configuration between the anomeric aryl substituents, representative of the C-7 and C-7' substituents in the natural products. Further, our results show that stereocontrol is under kinetic control, and calculations suggest that a favorable pi-stacking interaction may be the source of this stereocontrol.
authors.affiliation: Department of Chemistry, Mississippi State University, Mississippi State, Mississippi 39762, USA.
authors.forename: Sidika Polat
authors.initials: SP
authors.lastname: Cakir
authors.forename: Sean
authors.initials: S
authors.lastname: Stokes
authors.forename: Andrzej
authors.initials: A
authors.lastname: Sygula
authors.forename: Keith T
authors.initials: KT
authors.lastname: Mead
mesh_terms: D032429:Alpinia / Q000737:chemistry; D003500:Cyclization; D036381:Diarylheptanoids / Q000138:chemical synthesis* / Q000737:chemistry / Q000302:isolation & purification; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D036381:Diarylheptanoids; C410688:calyxin I; C545382:calyxin J; C545383:epicalyxin J