905-14-6Relevant academic research and scientific papers
Method of synthesizing compounds having a phosphorus-fluorine-18 bond
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Page/Page column 3, (2008/06/13)
Provided are methods for synthesizing radiotracers, including no carrier added (n.c.a.) tracers suitable as PET scan tracers that contain a 18F—P bond. The radiolabeled products may be synthesized from precursors including phosphorus(V) and/or phosphorus (III) atoms bound to a suitable leaving group or group(s). For example, precursors incorporating a nitrophenoxy leaving group bound to a phosphorus(V) atom tend to exhibit an acceptable combination of stability and reactivity and also tend to allow the precursor compound(s) to be separated more easily from the 18F-labeled products. The methods disclosed herein for producing radiolabeled compounds incorporating a P—18F chemistry may particularly useful radiolabeling oligonucleotides, phospholipids, phosphorilated proteins, sugars and steroids for use as PET radiotracer compounds for medical imaging applications.
Design of experiments on the transesterification of tris(p-nitrophenyl) phosphate with sodium methoxide
Seiceira, Rafael C.,Nakayama, Hatumi T.,Costa Neto, Claudio,Cajaiba Da Silva, Joao F.,Pedrosa, Marcelo S.
, p. 389 - 395 (2007/10/03)
A design of experiments was conducted to study the transesterification of tris(p-nitrophenyl) phosphate with sodium methoxide. The factorial design was performed to check the experimental conditions that favored ths yield of bis(p-nitrophenyl) methyl phosphate in a semi-batch process. The experiments were performed using a Mettler RC1 calorimeter. The reaction temperature, the addition order of reagents and the time spent in those additions were analyzed at two different levels. The results showed the addition order of reagents as the most important factor to guarantee the improvement of the reaction yielding bis(p-nitrophenyl) methyl phosphate. It was demonstrated that the temperature has a small effect on the reaction yield between 5 and 30°C. An important effect was observed with regard to the addition time of reagents and yield: when the tris(p-nitrophenyl)phosphate is added to the methoxide solution (58% on average) while no effect was observed when the methoxide solution was added to the phosphate (87% on average). Theses results indicated that the addition could be made in times shorter than five minutes under the latter condition. Copyright Taylor & Francis Inc.
Nucleophilic Cleavage of Phosphate Triesters in Dialkylammonium Bilayer Membranes
Okahata, Yoshio,Ihara, Hirotaka,Kunitake, Toyoki
, p. 2072 - 2078 (2007/10/02)
A study was carried out on the reaction of p-nitrophenyl phosphates with hydroxamate nucleophiles in water in the presence of dialkylammonium bilayer membranes.With ethyl bis(p-nitrophenyl) phosphate, clean second-order kinetics was observed for all the hydroxamate nucleophiles, two equivalents of p-nitrophenol being released in most cases.In contrast, a complex kinetics was observed for octadecylbis(p-nitrophenyl)phosphate.The second cleavage process of this long-chain substrate by a long-chain hydroxamate was affected by the fluidity of the matrix membrane, an inflection region being present in the Arrhenius plots near the phase transition temperature (Tc) of the 2C16N+2C1 membrane.The activation energy was 14 and 21 kcal/mol at temperatures above and below Tc, respectively.Similar changes in the activation energy had been observed for decarboxylation and proton abstraction.
