title: Antimycobacterial N-alkoxyphenylhydroxynaphthalenecarboxamides affecting photosystem II.
abstract: N-(Alkoxyphenyl)-2-hydroxynaphthalene-1-carboxamides (series A) and N-(alkoxyphenyl)-1-hydroxynaphthalene-2-carboxamides (series B) affecting photosystem (PS) II inhibited photosynthetic electron transport (PET) in spinach chloroplasts. Their inhibitory activity depended on the compound lipophilicity as well as on the position of the alkoxy substituent. The most potent PET inhibitors were 2-hydroxy-N-phenylnaphthalene-1-carboxamide and N-[3-(but-2-yloxy)phenyl]-2-hydroxynaphthalene-1-carboxamide within series A (IC50=28.9 and 42.5µM, respectively) and 1-hydroxy-N-(3-propoxyphenyl)naphthalene-2-carboxamide and 1-hydroxy-N-(3-ethoxyphenyl)-naphthalene-2-carboxamide (IC50=2.0 and 3.1µM, respectively) within series B. The inhibitory activity of C'(3)or C'(4)alkoxy substituted compounds of series B was considerably higher than that of C'(2)ones within series A. The PET-inhibiting activities of both series were compared with the PET inhibition of isomeric N-alkoxyphenyl-3-hydroxynaphthalene-2-carboxamides (series C) reported recently. Interactions of the studied compounds with chlorophyll a and aromatic amino acids present in pigment-protein complexes mainly in PS II were documented by fluorescence spectroscopy. The section between P680and plastoquinone QBin the PET chain occurring on the acceptor side of PSII can be suggested as the site of action of the compounds.
authors.affiliation: Department of Chemical Drugs, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences, Palackeho 1, 612 42 Brno, Czech Republic. Electronic address: t.gonec@seznam.cz.
authors.forename: Tomas
authors.initials: T
authors.lastname: Gonec
authors.affiliation: Institute of Chemistry, Faculty of Natural Sciences, Comenius University, Ilkovicova 6, 842 15 Bratislava, Slovakia.
authors.forename: Katarina
authors.initials: K
authors.lastname: Kralova
authors.affiliation: Department of Environmental Ecology, Faculty of Natural Sciences, Comenius University, Ilkovicova 6, 842 15 Bratislava, Slovakia.
authors.forename: Matus
authors.initials: M
authors.lastname: Pesko
authors.affiliation: Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Comenius University, Odbojarov 10, 832 32 Bratislava, Slovakia. Electronic address: josef.jampilek@gmail.com.
authors.forename: Josef
authors.initials: J
authors.lastname: Jampilek
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000378:metabolism*; D004579:Electron Transport / Q000187:drug effects; D009281:Naphthalenes / Q000737:chemistry / Q000378:metabolism*; D045332:Photosystem II Protein Complex / Q000037:antagonists & inhibitors* / Q000378:metabolism; D010940:Plant Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D018724:Spinacia oleracea / Q000187:drug effects* / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D009281:Naphthalenes; D045332:Photosystem II Protein Complex; D010940:Plant Proteins
keywords: Hill reaction; Hydroxynaphthalenecarboxamides; Photosystem II; Structure–activity relationships