title: Synthesis of a new scaffold: the 7H,8H-pyrimido[1,6-b]pyridazin-6,8-dione nucleus.
abstract: This paper describes a modified method of preparation of a number of alpha-aryl-alpha-(pyridazin-3-yl)-acetonitriles via the C-arylation reaction of the corresponding carbanionsof phenylacetonitriles using 3-chloropyridazine derivatives. KOH and DMSO were used inthe deprotonation process, which made the reaction very simple and safe to perform.Nitriles were obtained in the hydrolysis reaction to the corresponding alpha-aryl-alpha-(pyridazin-3-yl)-acetamide derivatives, which were next subjected to cyclization to afford the finalproducts. A number of new derivatives of 7H,8H-pyrimido[1,6-b]pyridazin-6,8-dione weresynthesized in the cyclocondensation reaction of respective alpha-aryl-alpha-(pyridazin-3-yl)-acetamides with diethyl carbonate in the presence of EtONa. The structure andcomposition of the new compounds were confirmed by IR, (1)H- and (13)C- NMR analysesand by elemental C, H and N analysis.
authors.affiliation: Department of Drug Technology, Faculty of Pharmacy, Medical University of Warsaw, Banacha 1 Str., 02-097 Warsaw, Poland. herold@farm.amwaw.edu.pl
authors.forename: Franciszek
authors.initials: F
authors.lastname: Herold
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Kałucka
authors.forename: Marek
authors.initials: M
authors.lastname: Król
authors.forename: Joanna
authors.initials: J
authors.lastname: Herold
authors.forename: Jerzy
authors.initials: J
authors.lastname: Kleps
authors.forename: Jadwiga
authors.initials: J
authors.lastname: Turło
mesh_terms: D009682:Magnetic Resonance Spectroscopy; D011724:Pyridazines / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D011724:Pyridazines