title: 2-[(R-phenyl)amine]-1,4-naphthalendiones as photosystem I electron acceptors: structure-activity relationship of m- and p-PAN compounds with QSAR analysis.
abstract: Nineteen 2-[(R-phenyl)amine]-1,4-naphthalendione derivatives (PAN) were tested on spinach thylakoids for their activity as electron acceptors. These molecules act as photosystem I electron acceptors in the micromolar range. AC(50) values varied from 5 nM to 24 microM. QSAR analysis revealed a linear correlation of the m-PAN derivative log [1/AC(50)] with the energy difference of the LUMO and HOMO orbitals. The biological activity of p-PAN derivatives correlates linearly with structural parameters. Electron affinity is being the most important. The half wave I potential values (E(1/2)) of PAN compounds (from -213 to -569 mV vs. NHE) match with the mid-point potentials of the A(0) to F(X) niche of PSI electron transport carriers. The logP values of PAN derivatives were 3.35 and 3.88, indicating that they are hydrophobic compounds. Therefore PAN compounds accept electrons at the hydrophobic A(0) to F(X) niche of PSI.
authors.affiliation: Departamento de Bioquímica, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, México, DF 04510, Mexico.
authors.forename: Beatriz
authors.initials: B
authors.lastname: King-Díaz
authors.forename: Norma A
authors.initials: NA
authors.lastname: Macías-Ruvalcaba
authors.forename: Martha
authors.initials: M
authors.lastname: Aguilar-Martínez
authors.forename: Patrizia
authors.initials: P
authors.lastname: Calaminici
authors.forename: Andreas M
authors.initials: AM
authors.lastname: Köster
authors.forename: Zeferino
authors.initials: Z
authors.lastname: Gómez-Sandoval
authors.forename: J U
authors.initials: JU
authors.lastname: Reveles
authors.forename: Blas
authors.initials: B
authors.lastname: Lotina-Hennsen
mesh_terms: D000255:Adenosine Triphosphate / Q000096:biosynthesis; D004579:Electron Transport / Q000187:drug effects; D007536:Isomerism; D007700:Kinetics; D009285:Naphthoquinones / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology*; D018462:Photobiology; D045331:Photosystem I Protein Complex / Q000187:drug effects* / Q000378:metabolism*; D021281:Quantitative Structure-Activity Relationship; D018724:Spinacia oleracea / Q000187:drug effects / Q000378:metabolism; D020524:Thylakoids / Q000187:drug effects / Q000378:metabolism
chemical_list: D009285:Naphthoquinones; D045331:Photosystem I Protein Complex; D000255:Adenosine Triphosphate