title: Expedient entry to the piperazinohydroisoquinoline ring system using a sequential Ugi/Pictet-Spengler/reductive methylation reaction protocol.
abstract: An expedient entry to the piperazinohydroisoquinoline ring system present in the tetrahydroisoquinoline antitumor alkaloids family is described. The synthetic sequence involves: a sequential Ugi reaction followed by an N-Boc-deprotection process and iminium formation with a spontaneous Pictet-Spengler cyclization and reductive N-methylation, with all these processes performed in a two-operation protocol in the same reaction flask.
authors: Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, Coyoacán México DF 04510, México.
authors: Ma-Angeles
authors: MA
authors: Cano-Herrera
authors: Luis D
authors: LD
authors: Miranda
mesh_terms: D000470:Alkaloids / Q000138:chemical synthesis / Q000737:chemistry; D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry; D018360:Crystallography, X-Ray; D003500:Cyclization; D007546:Isoquinolines / Q000138:chemical synthesis / Q000737:chemistry*; D008745:Methylation; D008968:Molecular Conformation; D010084:Oxidation-Reduction; D000077489:Piperazine; D010879:Piperazines / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000470:Alkaloids; D000970:Antineoplastic Agents; D007546:Isoquinolines; D010879:Piperazines; D000077489:Piperazine; C039109:isoquinoline