title: Phosphorus-nitrogen donor interaction leading to atrane formation in phosphate and oxyphosphorane compositions. Implications for phosphoryl transfer enzymes(1).
abstract: Reaction of aminotriphenols, tris(2-hydroxy-3,5-dimethylbenzyl)amine (E) and tris(2- hydroxy-3-tert-butyl-5-methylbenzyl)amine (F), with triphenylphosphite, tris(p-methoxyphenyl)phosphite, or phenyldiphenoxyphosphane in the presence of N-chlorodiisopropylamine led to the isolation of tetraoxyphosphorane 1, pentaoxyphosphorane 3, phosphate-atrane 2, hexacoordinated pentaoxyphosphorane-atrane 4, and the first hexacoordinated tetraoxyphosphorane-atrane 5. X-ray analysis of 1-3 and 5 were obtained. NMR data is reported and supports that the atrane 4 has the same hexacoordinated structure as 5. Phosphate 2 reveals weak phosphorus-nitrogen donor action whereas the hexacoordinated atranes 4 and 5 have pronounced P-N coordination. The results are used to support amino acid donor action occurring at active sites of phosphoryl transfer enzymes. Increased strength of donor action in the higher-coordinate model activated state compared to that in the substrate phosphate composition should serve as a factor in enhancing enzyme reaction rates.
authors.affiliation: Department of Chemistry, University of Massachusetts, Amherst, MA 01003-9336, USA.
authors.forename: Natalya V
authors.initials: NV
authors.lastname: Timosheva
authors.forename: A
authors.initials: A
authors.lastname: Chandrasekaran
authors.forename: Robert R
authors.initials: RR
authors.lastname: Holmes
mesh_terms: D002384:Catalysis; D018360:Crystallography, X-Ray; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D009584:Nitrogen / Q000737:chemistry*; D009943:Organophosphorus Compounds / Q000138:chemical synthesis*; D010758:Phosphorus / Q000737:chemistry*; D010770:Phosphotransferases / Q000737:chemistry*
chemical_list: D009943:Organophosphorus Compounds; D010758:Phosphorus; D010770:Phosphotransferases; D009584:Nitrogen