title: Synthesis of new trans-2-benzyl-3-(furan-2-yl)-4-substituted-1,2,3,4-tetrahydroisoquinolinones.
abstract: The reaction of homophthalic anhydride and N-(furan-2-yl-methylidene)- benzylamine in different solvents and varying temperatures was studied in detail. Mixtures of the expected trans- and cis-1,2,3,4-tetrahydroisoquinoline-4-carboxylic acids trans-5 and cis-5, along with by-products 6 and 7 were obtained in dichloroethane or benzene. In pyridine, used for the first time, the reaction became completely diastereoselective, giving only the trans isomer. The carboxylic acid group of trans-5 was transformed in four steps into cyclic aminomethyl groups which yielded various new tetrahydroisoquinolinones trans- 11a-g, incorporating both a known fragment of pharmacological interest and various pharmacophoric substituents.
authors.affiliation: Department of Chemistry, University of Sofia, 1 James Bouchier Avenue, Sofia 1164, Bulgaria.
authors.forename: Meglena I
authors.initials: MI
authors.lastname: Kandinska
authors.forename: Ivan D
authors.initials: ID
authors.lastname: Kozekov
authors.forename: Mariana D
authors.initials: MD
authors.lastname: Palamareva
mesh_terms: D001578:Benzopyrans / Q000737:chemistry; D007097:Imines / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D013237:Stereoisomerism; D044005:Tetrahydroisoquinolines / Q000138:chemical synthesis*
chemical_list: D001578:Benzopyrans; D007097:Imines; D044005:Tetrahydroisoquinolines; C001354:homophthalic acid anhydride