title: Recent developments in the synthesis of acetylcholinesterase inhibitors.
abstract: The acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activities of a series of pyrano[2,3-b]quinolines (2, 3), [1,8]naphthyridines (5, 6), 4-amino-2,3-diaryl-5,6,7,8-tetrahydrofuro[2,3-b]quinolines (11-13)/ 4-amino-6,7,8,9-tetrahydro-2,3-diphenyl-5H-cyclohepta[e]furo[2,3-b]pyridine (14), 4-amino-5,6,7,8-tetrahydro-2,3-diphenylthieno[2,3-b]quinoline (15)/ 4-amino-6,7,8,9-tetrahydro-2,3-diphenyl-5H-cyclohepta[e]thieno[2,3-b]pyridine (16) are described. These compounds are tacrine analogues that have been prepared from readily available polyfunctionalized ethyl [6-amino-5-cyano-4H-pyran]-3-carboxylates (9, 10), ethyl [6-amino-5-cyanopyridine]-3-carboxylates (7, 8), 2-amino-3-cyano-4,5-diarylfurans (17-19) and 2-amino-3-cyano-4,5-diphenylthiophene (20) via Friedländer condensation with selected ketones. These compounds are competitive and, in a few cases, non-competitive inhibitors for AChE, the most potent being compound (14), though three-fold less active than tacrine. The BuChE inhibitory activity is only significant in compounds 11 and 14, ten-fold less active than tacrine. Furthermore, the products 12 and 13 are selective and moderate AChE inhibitors.
authors.affiliation: Laboratorio de Radicales Libres, C/ Juan de la Cierva, 3, 28006-Madrid, Spain. iqoc21@iqog.csic.es
authors.forename: José L
authors.initials: JL
authors.lastname: Marco
authors.forename: M Carmo
authors.initials: MC
authors.lastname: Carreiras
mesh_terms: D000110:Acetylcholinesterase / Q000187:drug effects*; D002091:Butyrylcholinesterase / Q000187:drug effects; D002800:Cholinesterase Inhibitors / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D015394:Molecular Structure; D011725:Pyridines / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D011804:Quinolines / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D013329:Structure-Activity Relationship; D013619:Tacrine / Q000031:analogs & derivatives / Q000494:pharmacology
chemical_list: D002800:Cholinesterase Inhibitors; D011725:Pyridines; D011804:Quinolines; D013619:Tacrine; D000110:Acetylcholinesterase; D002091:Butyrylcholinesterase