title: Novel coumarins and 2-thioxo-coumarins as inhibitors of the tumor-associated carbonic anhydrases IX and XII.
abstract: A series of coumarins incorporating tert-butyl-dimethylsilyloxy- or allyoxy- moieties in positions 4-, 6 or 7 of the heterocyclic ring have been synthesized and then converted to the corresponding 2-thioxo-coumarins. Other derivatives incorporating hydroxyethyloxy-, tosylethoxy- and 2-fluroethyloxy- moieties in position 7 of the coumarin ring were synthesized together with derivatives of 4-methyl-7-amino coumarin incorporating acetamido, 3,5-dimethylphenylureido- and tert-butyloxycarbonylamido functionalities. All these compounds were assayed as inhibitors of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1). The human (h) cytosolic isoforms hCA I and II were weakly inhibited (hCA I) or not inhibited at all (hCA II) by these (thioxo)coumarins whereas the tumor-associated transmembrane isoforms hCA IX and XII were inhibited with efficiencies from the submicromolar to the low micromolar range by many of these derivatives. The structure-activity relationship for these classes of less investigated CA inhibitors are delineated, with the potential of using them as leads to obtain isoform-selective inhibitors with excellent affinity for CA IX and XII (validated antitumor targets) which do not significantly inhibit the cytosolic offtarget isoforms hCA I and II.
authors.affiliation: Università degli Studi di Firenze, Polo Scientifico, Laboratorio di Chimica Bioinorganica, Rm. 188, Via della Lastruccia 3, 50019 Sesto Fiorentino (Florence), Italy.
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Carta
authors.forename: Alfonso
authors.initials: A
authors.lastname: Maresca
authors.forename: Andrea
authors.initials: A
authors.lastname: Scozzafava
authors.forename: Claudiu T
authors.initials: CT
authors.lastname: Supuran
mesh_terms: D000951:Antigens, Neoplasm / Q000737:chemistry* / Q000378:metabolism; D000071231:Carbonic Anhydrase IX; D002257:Carbonic Anhydrase Inhibitors / Q000138:chemical synthesis / Q000737:chemistry* / Q000627:therapeutic use; D002256:Carbonic Anhydrases / Q000737:chemistry* / Q000378:metabolism; D003374:Coumarins / Q000138:chemical synthesis / Q000737:chemistry* / Q000627:therapeutic use; D006801:Humans; D009369:Neoplasms / Q000188:drug therapy / Q000201:enzymology*; D013329:Structure-Activity Relationship
chemical_list: D000951:Antigens, Neoplasm; D002257:Carbonic Anhydrase Inhibitors; D003374:Coumarins; C089226:CA9 protein, human; D000071231:Carbonic Anhydrase IX; D002256:Carbonic Anhydrases; C477378:carbonic anhydrase XII