title: Naphthalene analogues of lignans.
abstract: The methodology for the synthesis of podophyllotoxin and thuriferic acid-type lignans has been applied to derivatives carrying a naphthalene moiety. Starting from the 1,3-dithiane of 2-naphthaldehyde afforded the expected analogues in the 2,1-naphthalene series. The preferred conformations of these compounds are influenced by the bulky naphthalene system. By contrast, 1,8-bridged products were obtained from the 1,3-dithiane of 1-naphthaldehyde. In this series, polycyclic naphthalene lignan analogues were isolated after deprotection and/or desulfurization reactions. The cyclizations produced in this process are due to the proximity between the 3,4,5-trimethoxyphenyl moiety and the reacting C-2 of the 1,3-dithiane ring.
authors.affiliation: Laboratorio de Química Orgánica y Farmacéutica, Facultad de Farmacia, Universidad de Salamanca, Campus Miguel de Unamuno, E-37007 Salamanca, Spain.
authors.forename: Blanca
authors.initials: B
authors.lastname: Madrigal
authors.forename: Pilar
authors.initials: P
authors.lastname: Puebla
authors.forename: Rafael
authors.initials: R
authors.lastname: Peláez
authors.forename: Esther
authors.initials: E
authors.lastname: Caballero
authors.forename: Manuel
authors.initials: M
authors.lastname: Medarde
mesh_terms: D002227:Carbazoles / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D002625:Chemistry, Organic / Q000379:methods; D003500:Cyclization; D004951:Esterification; D007202:Indicators and Reagents; D017705:Lignans / Q000138:chemical synthesis* / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009281:Naphthalenes / Q000138:chemical synthesis* / Q000737:chemistry; D011034:Podophyllotoxin / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D002227:Carbazoles; D007202:Indicators and Reagents; D017705:Lignans; D009281:Naphthalenes; C452999:thuriferic acid; C031721:naphthalene; D011034:Podophyllotoxin