Synthesis of New Tetraethyl(N-alkyl-1-aminoethan-1,1- diyl)bisphosphonates and ESR Analysis of Chemical Exchange of Derived Nitroxides of Acyclic Aminobisphosphonates. Short Title: ESR analysis of nitroxides of aminobisphosphonates
نویسندگان
چکیده
The synthesis and the full characterization of two new linear bisphosphonates (tetraethyl(Ntertbutyl-1-aminoethan-1,1-diyl)bisphosphonate and tetraethyl(N-secbutyl-1-aminoethan-1,1diyl)bisphosphonate) and the first analysis of the ESR spectra of the corresponding nitroxides is reported. The preliminary results of theoretical calculations on model compounds suggest a small B0 (in the McConnell equation). The results of bisphosphonate ester and bisphosphonic ∗ To whom correspondence should be addressed. Current address: EICVN, Rue Pépin, 2b, 5000 Namur, Belgium. E-mail: [email protected]. ha l-0 06 62 55 8, v er si on 1 24 J an 2 01 2 Author manuscript, published in "Phosphorus, Sulfur, and Silicon and the Related Elements 182, 10 (2007) 2359-2369" G. Olive et al., Synthesis of New Tetraethyl(N-alkyl-1-aminoethan-1,1-diyl.... 2 acid are similar. The discrepancies of P coupling for the diphosphorus compound stems from B2 that is different when the dihedral angle is larger than 90 degree.
منابع مشابه
Mechanism of Polymer Stabilization by Hindered-Amine Light Stabilizers (HALS). Model Investigations of the Interaction of Peroxy Radicals with HALS Amines and Amino Ethers
Peroxy radicals, when generated in the presence of hindered-amine light stabilizers (HALS), oxidized HALS to produce nitroxides. This reaction, in addition to the scavenging of alkyl radicals by nitroxides, forms a cycle describing HALS as a class of excellent polymer stabilizers. As model systems for the mechanism of the oxidation of HALS, both alkyl peroxy and acyl peroxy radicals were produc...
متن کاملThe use of nitroxides in viable biological systems: an opportunity and challenge for chemists and biochemists
This article attempts to provide an overview of recent developments in the use of nitroxides to study viable biological systems by magnetic resonance, especially electron spin resonance (ESR or EPR) techniques. These magnetic resonance approaches include studies in intact animals and imaging in up to four dimensions. The goal of this article is to stimulate chemists and biochemists to participa...
متن کاملSite-directed spin labeling of 2'-amino groups in RNA with isoindoline nitroxides that are resistant to reduction.
Two aromatic isothiocyanates, derived from isoindoline nitroxides, were synthesized and selectively reacted with 2'-amino groups in RNA. The spin labels displayed limited mobility in RNA, making them promising candidates for distance measurements by pulsed EPR. After conjugation to RNA, a tetraethyl isoindoline derivative showed significant stability under reducing conditions.
متن کاملSynthesis, Spectroscopy and Magnetic Characterization of Five Dinuclear Copper(II) Complexes with 2, 3 or 4-Pyridinemethanol as the Ligand
The synthesis, spectroscopy and magnetic characterization of five new dinuclear copper(II) complexes are described. All five compounds have the general formula [Cu2(L)4(O-R)2](Cl)2 or [Cu2(L)2(Cl)2](Cl)2, in which R = CH3 or H, L=2, 3 or 4-pyridinemethanol as L2, L3 or L4, respectively. The title compounds consist of dinuclear units with bridging methoxo groups in [Cu2(L4)4(O-CH3)2](Cl)2, hydro...
متن کامل