title: Regio- and diastereoselective synthesis and X-ray structure determination of (+)-2-deoxyoryzalexin S from (+)-podocarpic acid. Structural nonidentity with its nominal natural isolated enantiomer.
abstract: (+)-2-Deoxyoryzalexin S (1), the nominal enantiomer of a diterpenoid isolated in Chile from Calceolaria species, was regio- and diastereoselectively synthesized from (+)-podocarpic acid. (+)-2-Deoxyoryzalexin S (1) was characterized also as its acetyl derivative, (+)-2, whose structure was confirmed by X-ray crystallographic analysis. Surprisingly, comparison of the data recorded for (+)-1 and (+)-2 and those reported in the literature for the Calceolaria isolated diterpenoid 1 and its derivative (-)-2 showed some differences, suggesting that the latter do not possess the proposed structures.
authors.affiliation: Dipartimento di Chimica, Università degli Studi di Roma "La Sapienza" , P.le Aldo Moro, 5, I-00185 Roma, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Leonelli
authors.forename: Valentina
authors.initials: V
authors.lastname: Latini
authors.forename: Andrea
authors.initials: A
authors.lastname: Trombetta
authors.forename: Gabriele
authors.initials: G
authors.lastname: Bartoli
authors.forename: Francesca
authors.initials: F
authors.lastname: Ceccacci
authors.forename: Angela
authors.initials: A
authors.lastname: La Bella
authors.forename: Alessio
authors.initials: A
authors.lastname: Sferrazza
authors.forename: Doriano
authors.initials: D
authors.lastname: Lamba
authors.forename: Luisa M
authors.initials: LM
authors.lastname: Migneco
authors.forename: Rinaldo Marini
authors.initials: RM
authors.lastname: Bettolo
mesh_terms: D045784:Abietanes / Q000737:chemistry*; D002677:Chile; D018360:Crystallography, X-Ray; D004224:Diterpenes; D008958:Models, Molecular; D015394:Molecular Structure; D028083:Scrophulariaceae / Q000737:chemistry*; D013237:Stereoisomerism; D013329:Structure-Activity Relationship
chemical_list: C587745:(+)-2-deoxyoryzalexin S; D045784:Abietanes; D004224:Diterpenes; C002470:podocarpic acid