title: Tyrosine-like condensed derivatives as tyrosinase inhibitors.
abstract: OBJECTIVE
  We report the pharmacological evaluation of a new series of 3-aminocoumarins differently substituted with hydroxyl groups, which have been synthesized because they include in their structures the tyrosine fragment (tyrosine-like compounds), with the aim of discovering structural features necessary for tyrosinase inhibitory activity.
  
  
  METHODS
  The synthesized compounds 4 and 7-9 were evaluated in vitro as mushroom tyrosinase inhibitors.
  
  
  RESULTS
  Two of the described compounds showed lower IC50 (concentration giving 50% inhibition of tyrosinase activity) than umbelliferone, used as a reference compound.
  
  
  CONCLUSIONS
  Compound 7 (IC50=53µm) was the best tyrosinase inhibitor of this small series, having an IC50 value 10-fold lower than umbelliferone. Compound 7 (3-amino-7-hydroxycoumarin) had amino and hydroxyl groups precisely mimicking the same positions that both groups occupy on the tyrosine molecule.
authors.affiliation: Departamento de Química Orgánica, Facultad de Farmacia, Universidad de Santiago de Compostela, Santiago de Compostela, Spain. mariajoao.correiapinto@rai.usc.es
authors.forename: Maria João
authors.initials: MJ
authors.lastname: Matos
authors.forename: Lourdes
authors.initials: L
authors.lastname: Santana
authors.forename: Eugenio
authors.initials: E
authors.lastname: Uriarte
authors.forename: Silvia
authors.initials: S
authors.lastname: Serra
authors.forename: Marcella
authors.initials: M
authors.lastname: Corda
authors.forename: Maria Benedetta
authors.initials: MB
authors.lastname: Fadda
authors.forename: Benedetta
authors.initials: B
authors.lastname: Era
authors.forename: Antonella
authors.initials: A
authors.lastname: Fais
mesh_terms: D000363:Agaricales / Q000201:enzymology; D020128:Inhibitory Concentration 50; D015394:Molecular Structure; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors*; D012016:Reference Values; D014443:Tyrosine / Q000737:chemistry*; D014468:Umbelliferones / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*
chemical_list: C574002:3-amino-7-hydroxycoumarin; D014468:Umbelliferones; D014443:Tyrosine; C031477:7-hydroxycoumarin; D014442:Monophenol Monooxygenase