title: A short synthetic route towards merosesquiterpenes with a benzoxanthene skeleton.
abstract: A short synthetic sequence for the preparation of merosesquiterpenes with a benzoxanthene skeleton starting from commercial (-)-sclareol is reported. The D ring of the target compound is obtained through a Diels-Alder cycloaddition, involving a dienoldiether derived from a tricyclic α,β-enone synthesized in two steps from the starting diterpene. Utilizing this procedure, the preparation of (+)-hongoquercin A and the first synthesis of (+)-cyclospongiaquinone-1 were achieved.
authors.affiliation: Departamento de Química Orgánica, Facultad de Ciencias, Instituto de Biotecnología, Universidad de Granada, 18071 Granada, Spain. eamr@ugr.es rachid@ugr.es.
authors.forename: Antonio
authors.initials: A
authors.lastname: Fernández
authors.forename: Esteban
authors.initials: E
authors.lastname: Alvarez
authors.forename: Ramón
authors.initials: R
authors.lastname: Alvarez-Manzaneda
authors.forename: Rachid
authors.initials: R
authors.lastname: Chahboun
authors.forename: Enrique
authors.initials: E
authors.lastname: Alvarez-Manzaneda
mesh_terms: D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry; D061565:Cycloaddition Reaction; D004224:Diterpenes / Q000737:chemistry; D012717:Sesquiterpenes / Q000138:chemical synthesis / Q000737:chemistry*; D013237:Stereoisomerism; D014966:Xanthenes / Q000737:chemistry*
chemical_list: D000970:Antineoplastic Agents; D004224:Diterpenes; D012717:Sesquiterpenes; D014966:Xanthenes; C000598290:cyclospongiaquinone-1; C114155:hongoquercin A; C070760:sclareol