Sala, Martin;Makuc, Damjan;Kolar, Jana;Plavec, Janez;Pihlar, Boris published 《Potentiometric and 31P NMR studies on inositol phosphates and their interaction with iron(III) ions》 in 2011. The article was appeared in 《Carbohydrate Research》. They have made some progress in their research.Reference of rel-(1R,2r,3S,4R,5s,6S)-Cyclohexane-1,2,3,4,5,6-hexayl hexakis(dihydrogen phosphate), dipotassium salt The article mentions the following:
Potentiometric, conductometric and 31P NMR titrations have been applied to study interactions between myo-inositol hexakisphosphate (phytic acid), (±)-myo-inositol 1,2,3,5-tetrakisphosphate and (±)-myo-inositol 1,2,3-trisphosphate with iron(III) ions. Potentiometric and conductometric titrations of myo-inositol phosphates show that addition of iron increases acidity and consumption of hydroxide titrant. By increasing the Fe(III)/InsP6 ratio (from 0.5 to 4) 3 mol of protons are released per 2 mol of iron(III). At first, phytates coordinate iron octahedrally between P2 and P1,3. The second coordination site represents P5 and neighboring P4,6 phosphate groups. Complexation is accompanied with the deprotonation of P1,3 and P4,6 phosphate oxygens. At higher concentration of iron(III) intermol. P-O-Fe-O-P bonds trigger formation of a polymeric network and precipitation of the amorphous Fe(III)-InsP6 aggregates. 31P NMR titration data complement the above results and display the largest chem. shift changes at pD values between 5 and 10 in agreement with strong interactions between iron and myo-inositol phosphates. The differences in T1 relaxation times of phosphorous atoms have shown that phosphate groups at positions 1, 2 and 3 are complexated with iron(III). The interactions between iron(III) ions and inositol phosphates depend significantly on the metal to ligand ratio and an attempt to coordinate more than two irons per InsP6 mol. results in an unstable heterogeneous system. And rel-(1R,2r,3S,4R,5s,6S)-Cyclohexane-1,2,3,4,5,6-hexayl hexakis(dihydrogen phosphate), dipotassium salt (cas: 129832-03-7) was used in the research process.
rel-(1R,2r,3S,4R,5s,6S)-Cyclohexane-1,2,3,4,5,6-hexayl hexakis(dihydrogen phosphate), dipotassium salt (cas:129832-03-7) is also known as Inositol hexakisphosphate. Phytic acid dipotassium salt is a potent chelator of divalent and trivalent cations, and a major determinant of zinc bioavailability.Reference of rel-(1R,2r,3S,4R,5s,6S)-Cyclohexane-1,2,3,4,5,6-hexayl hexakis(dihydrogen phosphate), dipotassium salt
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