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[en] Preparation of new diphosphonic acid esters or of diphosphonates having a good chemical stability. They are suitable for general uses of phosphonates, specially as chelating or extracting agents of heavy metals. An example of uranium extraction from wet process phosphoric acid is given
[fr]Preparation de nouveaux esters diphosphoniques ou de diphosphonates possedant une bonne stabilite chimique. Ils conviennent aux usages generaux des phosphonates particulierement comme agents chelatants ou d'extraction pour les metaux lourds. On donne un exemple d'application a l'extraction d'uranium de l'acide phosphorique brut
[en] Preparation of new triphosphonic acid esters (or of phosphonates) with a good chemical stability. They are suitable for general uses of phosphonates, namely as chelating agents for heavy metals or for extraction of some metals (nickel, uranium, etc.). An example of uranium extraction is given
[fr]Preparation de nouveaux esters triphosphoniques (ou de phosphonates) qui presentent l'avantage d'une stabilite chimique, et conviennent a divers usages generaux des phosphonates connus. Ils sont notamment utiles comme chelatants de metaux lourds et comme agents d'extraction de certains metaux (nickel, uranium ou fer). On donne en exemple l'application a l'extraction de l'uranium
[en] The first synthesis of novel 5',5'-difluoro-30-hydroxy apiose nucleoside cyclomonophosphonic acid analogs was performed as potent anti-retroviral agents. Phosphonation was performed by direct displacement of a triflate intermediate with diethyl(lithiodifluoromethyl) phosphonate to give the corresponding(α, α-difluoroalkyl) phosphonate. Condensation successfully proceeded from a glycosyl donor with persilylated bases to yield the nucleoside phosphonate analogs. Deprotection of diethyl phosphonates provided the target nucleoside cyclomonophosphonic acid analogs. The synthesized nucleoside analogs were subjected to anti-viral screening against the human immunodeficiency virus-1 (HIV-1). Cytosine analogs show significant anti-HIV activity.
[en] Alkaline hydrolysis of N,N-disubstituted О,О-dialkyl (aminomethyl)phosphonates gives rise to the corresponding О-alkyl (aminomethyl)phosphonic acids. The reaction of potassium О-alkyl (aminomethyl)-phosphonates with organyl halides involves quaternization of the nitrogen atom to form dipolar aminophosphoryl compounds, aminophosphabetaines.
[en] The speciation of Plutonium in presence of chelating ligand in aqueous solution is extremely important in predicting its mobility and reactivity under environmental conditions. Furthermore, the coordination and structures of plutonium with chelating ligand in aqueous solution are especially important as these reflect the nature of this radioactive element in the environment as well as the ease with which it interacts with different ligands in the environment. Pu is a redox-sensitive element and one of the peculiarities of Pu chemistry is its variety of oxidation states from III to VII in aqueous solution and the relative stabilities of which are strongly affected by pH and the presence of complexing ligands. Thus precise identification of Pu speciation is tough which results in lack of accurate determination of electrochemical potentials and incomplete understanding of Pu redox reactions in presence of chelating agents. In this context, it is quite interesting to obtain the redox speciation of Pu with two Phosphonate ligands viz. Phenylphosphonic acid (PPA) and Aminotrismethylenephosphonic acid (ATMP)
[en] In this study, we synthesized 188Re-labeled phosphonic acid derivatives; ehtylenediaminetetramethylene phosphonate (EDTMP), 3,3-diphosphono-1,2-propanedicarboxylic acid (DPD) and dichloromethy lidene-1,1-bisphosphonate (Chlodronate), and compared in vivo biodistribution of 188Re-EDTMP with that of 188Re-HEDP. EDTMP 43 mg, DPD 13 mg, or chlodronate 20 mg was used. 50 μg NH4ReO4 and 0.7 mg, 1mg, and 3 mg of SnCl2 was used and it was incubated 15, 30, and 30 min at 100 .deg. C for 188Re-EDTMP. DPD and Chlodronate, respectively. All compounds were synthesized at pH=1, and adjusted to pH=6 with 3 M sodium acetate. Radiochemical purity and stability were checked by ITLC and Whatman paper 1. 188Re-HEDP was synthesized using established method, which is HEDP 15mg, SnCl2 3 mg, gentisic acid 4 mg, and NH4ReO4 50 μg at 100 .deg. C, 15 min. Animal experiment for 188Re-EDTMP and 188Re-HEDP was performed. After injection, organs were dissected and %ID/g was obtained at 4, 24, and 48 h (n= 4 for each group). 188Re complexes of all ligands showed > 95% radiochemical yields. Uptake (%ID/g) of 188Re-HEDP and EDTMP in femur was 1.11±0.07, 1.18±0.21 at 4 h; 0.79 ±0.07 and 0.87±0.24 at 24h; and 0.77±0.14 and 0.77±0.12 %ID/g at 48 h, respectively (p>0.05). For spine, 1.39±0.17, 1.15±0.15 ; 0.85±0.12. 0.81±0.04; 0.75 ±0.05, 0.64±0.10, respectively (p> 0.05). The 188Re-EDTMP uptake in the kidney was 0.629 %ID/g at 4 h but decline to 0.250 and 0.184 at 24 and 48 h, respectively. The radioactivities for 188Re-EDTMP in the lung, liver, muscle, and heart were all lower than 0.07 %ID/g at 4 h and also decline rapidly. Uptake of blood was slightly higher for 188Re-EDTMP at only 4 hours (0.036 vs 0.054 for 188Re-HEDP and EDTMP, respectively. P<0.05), and it decline to 0.01 and 0.004 %ID/g at 24 and 48 h, respectively. The ligands complexed with 188Re in high yield and all complexes showed good stability. 188Re-EDTMP showed similar or higher bone uptake with 188Re-HEDP
[en] Carbamoyl-phosphonic acid and carbamoyl-phosphonate ligands have been synthesized and studied for uranium extraction from phosphates ores. From a structure-selectivity approach, the molecular design of such ligands was optimized leading to a specific one called DEHCNPB which exhibits outstanding results for the selective extraction, and quantitative recovery of uranium in phosphoric acid compared to the URPHOS reference system. (authors)
[en] Phosphonic acids (PAs) are known to have a spontaneous affinity for chemisorption onto several metal oxide surfaces. The self – assembled monolayer (SAM) of phosphonates provides a platform for further surface modifications using biomolecules that can be adopted for the development of sensors and biosensors. With this in view, we studied adsorption kinetics of different phosphonic acids of short chain lengths such as phosphonopropionic acid (PPA), aminobenzylphosphonic acid (ABPA), benzylphosphonic acid (BPA), butylphosphonic acid (BuPA), and a long chain decylphosphonic acid (DecPA) on ITO surface using electrochemical impedance spectroscopy (EIS) at short and long time scales. The dependence of solution concentration on formation kinetics is studied and the existences of two discrete kinetics were revealed. We show from our studies that the rate of adsorption is controlled by diffusion at small time scales. Further, the phosphonic acid modified surface is also used as a substrate for the adsorption of cytochromeC (CytC) (a heme protein) and urease (an enzyme) and the kinetics of their adsorption has been studied.
[en] A composition for use in the preparation of a Technetium-99m bone-scanning agent comprises a mixture of ethylene glycol-1,2-bisphosphonic acid or a non-toxic salt thereof together with a reducing agent for pertechnetate. Technetium-99m, as an aqueous solution of pertechnetate, is added to the composition to form a complex of Technetium-99m and the bisphosphonate. The complex is useful as a bone-scanning agent and is rapidly taken up in the bone to give scans of high definition