title: 2-N-acylaminoalkylindoles: design and quantitative structure-activity relationship studies leading to MT2-selective melatonin antagonists.
abstract: Several indole analogues of melatonin (MLT) were obtained by moving the MLT side chain from C(3) to C(2) of the indole ring. Binding and in vitro functional assays were performed on cloned human MT1 and MT2 receptors, stably transfected in NIH3T3 cells. Quantitative structure-activity relationship studies showed that 4-methoxy-2-(N-acylaminomethyl)indoles, with a benzyl group in position 1, were selective MT2 antagonists and, in particular, N-[(1-p-chlorobenzyl-4-methoxy-1H-indol-2-yl)methyl]propanamide (12) behaved as a pure antagonist at MT1 and MT2 receptors, with a 148-fold selectivity for MT2. We present a topographical model that suggests a lipophilic group, located out of the plane of the indole ring of MLT, as the key feature of the MT2 selective antagonists.
authors.affiliation: Istituto di Chimica Farmaceutica e Tossicologica, Università degli Studi di Urbino, Italy. gilberto@uniurb.it
authors.forename: G
authors.initials: G
authors.lastname: Spadoni
authors.forename: C
authors.initials: C
authors.lastname: Balsamini
authors.forename: G
authors.initials: G
authors.lastname: Diamantini
authors.forename: A
authors.initials: A
authors.lastname: Tontini
authors.forename: G
authors.initials: G
authors.lastname: Tarzia
authors.forename: M
authors.initials: M
authors.lastname: Mor
authors.forename: S
authors.initials: S
authors.lastname: Rivara
authors.forename: P V
authors.initials: PV
authors.lastname: Plazzi
authors.forename: R
authors.initials: R
authors.lastname: Nonno
authors.forename: V
authors.initials: V
authors.lastname: Lucini
authors.forename: M
authors.initials: M
authors.lastname: Pannacci
authors.forename: F
authors.initials: F
authors.lastname: Fraschini
authors.forename: B M
authors.initials: BM
authors.lastname: Stankov
mesh_terms: D016475:3T3 Cells; D000818:Animals; D006801:Humans; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D051379:Mice; D008958:Models, Molecular; D021281:Quantitative Structure-Activity Relationship; D011956:Receptors, Cell Surface / Q000037:antagonists & inhibitors* / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear / Q000037:antagonists & inhibitors* / Q000378:metabolism; D044094:Receptors, Melatonin
chemical_list: D007211:Indoles; C435190:N-((1-(4-chlorobenzyl)-4-methoxy-1H-indol-2-yl)methyl)propanamide; D011956:Receptors, Cell Surface; D018160:Receptors, Cytoplasmic and Nuclear; D044094:Receptors, Melatonin