A new macrocyclic hexaamine ligand for the dissolution of human inorganic calculi.

Improved in Vivo Stability of Actinium-225 Macrocyclic Complexes

“…Saponification of the ester yielded PEPA and HEHA, and characterization was in agreement with the literature. 20,21 Quantitative complexation (>95%) of 225 Ac was obtained with all ligands within 30 min at 40 °C, pH 5.8, µ ) 0.1 M (NH 4 OAc), with the exception of PEPA where complexation was 80%. Actinium complexes, with the exception of Ac-acetate, were purified from a Chelex column prior to injection.…”

“…Previously, DTPA was used as a chelating agent for the removal of 227 Ac in an animal model. 21 Extremely high doses of DTPA were administered with little effect on the liver burden of 227 Ac. Recently, it has been estimated that CHX-A′′ DTPA provides ∼75% improvement in chelation over EDTA, but the toxicity due to 225 Ac leakage was still substantial.…”

“…A route modified from that previously reported , was employed for the preparation of PEPA and HEHA in an attempt to improve the yield. A two-step process, with overall yields of 79% and 48%, respectively, for PEPA and HEHA, was developed.…”

“…All spectra agreed with the literature values. 21 ) and adjusting the pH to near 5.0 by the addition of 5-10 µL of 1.0 M NH4OAc. The mixture was kept at 40 °C for 30 min and then purified on a Chelex column (∼300 µL of bed volume, preequilibrated with 0.1 M NH4OAc, pH ) 5.0), using 2 mL of NH4OAc solution as eluant.…”

Artificial Receptors for the Recognition of Phosphorylated Molecules

“…Alkyl functionalization of 11 led to receptor 12 , which was found to dissolve Ca 3 (PO 4 ) 2 more effectively than EDTA or 11 , displaying optimum activity at pH 7.0. 132 In a separate study, macrocycle 9 was functionalized with a lengthy alkyl chain ( 13 ) to give a derivative that was then used as the active component of an ATP selective electrode. 133 The electrode obtained in this case was found to function from pH 3.0 to 7.0, with a dynamic range of 10 -7 to 10 -3 M.…”