title: A divergent approach to benzylisoquinoline-type and oxoaporphine alkaloids via regioselective direct ring metalation of alkoxy isoquinolines.
abstract: Methoxy- and benzyloxy-substituted isoquinolines are regioselectively metalated at C-1 with the Knochel-Hauser base, subsequent trapping with aromatic aldehydes gives aryl(isoquinolin-1-yl)carbinols as building blocks for divergent syntheses of different types of benzylisoquinoline alkaloids. Photochemical cyclization of ortho-bromo analogues under reductive conditions gives oxoaporphine alkaloids. Nine benzylisoquinoline alkaloids and two oxoaporphine alkaloids were obtained in two or three steps from appropriate isoquinolines.
authors.affiliation: Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians University, Butenandtstr. 5-13, D-81377 Munich, Germany. Franz.Bracher@cup.uni-muenchen.de.
authors.forename: Benedikt
authors.initials: B
authors.lastname: Melzer
authors.forename: Franz
authors.initials: F
authors.lastname: Bracher
mesh_terms: D000470:Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry; D001060:Aporphines / Q000138:chemical synthesis* / Q000737:chemistry; D044182:Benzylisoquinolines / Q000138:chemical synthesis* / Q000737:chemistry; D007546:Isoquinolines / Q000737:chemistry*; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D000470:Alkaloids; D001060:Aporphines; D044182:Benzylisoquinolines; D007546:Isoquinolines