title: Naphtho[1,2-d]isothiazole acetic acid derivatives as a novel class of selective aldose reductase inhibitors.
abstract: Acetic acid derivatives of naphtho[1,2-d]isothiazole (NiT) were synthesized and tested as novel aldose reductase (ALR2) inhibitors. The parent compound 11 exhibited a fair inhibitory activity (IC(50) = 10 muM), which was enhanced by 2 orders of magnitude by introducing a second carboxylic group at position 4 (13 and 14: IC(50) = 0.55 and 0.14 muM, respectively). Substitution of the acetic acid function with an apolar group gave inactive (29) or poorly active (25, 26, 30) compounds, thus demonstrating that the 2-acetic group is involved in the enzyme pharmacophoric recognition while the 4-carboxylic moiety has only an accessory role. The potent compounds 11, 13, 14, 26 all proved to be selective for ALR2, since none of them inhibited aldehyde reductase, sorbitol dehydrogenase, or glutathione reductase. The isopropyl ester 31, a prodrug of 14, was found to be effective in preventing cataract development in severely galactosemic rats, when administered as an eyedrop solution. The theoretical binding mode of 13 and 14, obtained by docking simulations into the ALR2 crystal structure, was fully consistent with the structure-activity relationships in the NiT series.
authors.affiliation: Dipartimento di Scienze Farmaceutiche, Università di Pisa, Via Bonanno 6, 56126 Pisa, Italy.
authors.forename: Federico
authors.initials: F
authors.lastname: Da Settimo
authors.forename: Giampaolo
authors.initials: G
authors.lastname: Primofiore
authors.forename: Concettina
authors.initials: C
authors.lastname: La Motta
authors.forename: Stefania
authors.initials: S
authors.lastname: Sartini
authors.forename: Sabrina
authors.initials: S
authors.lastname: Taliani
authors.forename: Francesca
authors.initials: F
authors.lastname: Simorini
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Marini
authors.forename: Antonio
authors.initials: A
authors.lastname: Lavecchia
authors.forename: Ettore
authors.initials: E
authors.lastname: Novellino
authors.forename: Enrico
authors.initials: E
authors.lastname: Boldrini
mesh_terms: D000085:Acetates / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D000449:Aldehyde Reductase / Q000037:antagonists & inhibitors* / Q000737:chemistry; D000818:Animals; D001665:Binding Sites; D002386:Cataract / Q000209:etiology / Q000517:prevention & control; D018360:Crystallography, X-Ray; D005693:Galactosemias / Q000150:complications; D006801:Humans; D008958:Models, Molecular; D015394:Molecular Structure; D009281:Naphthalenes / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013329:Structure-Activity Relationship; D013844:Thiazoles / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000085:Acetates; D009281:Naphthalenes; D013844:Thiazoles; C484670:AKR1B1 protein, human; D000449:Aldehyde Reductase