title: Trans-fused iridoid glycosides from Penstemon mucronatus.
abstract: Two new trans-fused iridoid glycosides (5 alpha H)-6 alpha-8-epidihydrocornin and (5 alpha H)-6 alpha-8-hydroxy-8-epiloganin, were isolated from Penstemon mucronatus, along with cornin, penstemoside and three hastatosides. The trans-fused iridoids are only the second and third known among over 900 described cis-fused iridoid glycosides. Two pairs of iridoids, identical except for the stereochemistry at C-8, were found. Structures were determined by spectroscopic methods.
authors.affiliation: Department of Chemistry, Colorado State University, Fort Collins 80523, USA.
authors.forename: R E
authors.initials: RE
authors.lastname: Krull
authors.forename: F R
authors.initials: FR
authors.lastname: Stermitz
mesh_terms: D002236:Carbohydrate Conformation; D005960:Glucosides / Q000737:chemistry / Q000302:isolation & purification*; D057888:Iridoid Glucosides; D039823:Iridoids; D009682:Magnetic Resonance Spectroscopy; D010944:Plants / Q000737:chemistry*; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013237:Stereoisomerism
chemical_list: D005960:Glucosides; D057888:Iridoid Glucosides; D039823:Iridoids; C079206:pedicularioside; C091292:penstemonoside