471909-36-1Relevant articles and documents
Reactivation potency of fluorinated pyridinium oximes for acetylcholinesterases inhibited by paraoxon organophosphorus agent
Jeong, Hee Chun,Kang, Nam Sook,Park, No-Joong,Yum, Eul Kyun,Jung, Young-Sik
, p. 1214 - 1217 (2009)
For the purpose of developing new oxime reactivators of acetylcholinesterases (AChE) that have been inhibited by organophosphorus agents, emphasis was given to the finding that the lipophilic nature of fluorinated compounds is responsible for their enhanc
Reactivity and mechanism of α-nucleophile scaffolds as catalytic organophosphate scavengers
Wong, Pamela T.,Bhattacharjee, Somnath,Cannon, Jayme,Tang, Shengzhuang,Yang, Kelly,Bowden, Sierra,Varnau, Victoria,O'Konek, Jessica J.,Choi, Seok Ki
supporting information, p. 3951 - 3963 (2019/04/30)
Despite their unique benefits imparted by their structure and reactivity, certain α-nucleophile molecules remain underexplored as chemical inactivators for the topical decontamination of reactive organophosphates (OPs). Here, we present a library of thirty α-nucleophile scaffolds, each designed with either a pyridinium aldoxime (PAM) or hydroxamic acid (HA) α-nucleophile core tethered to a polar or charged scaffold for optimized physicochemical properties and reactivity. These library compounds were screened for their abilities to catalyze the hydrolysis of a model OP, paraoxon (POX), in kinetic assays. These screening experiments led to the identification of multiple lead compounds with the ability to inactivate POX two- to four-times more rapidly than Dekon 139 - the active ingredient currently used for skin decontamination of OPs. Our mechanistic studies, performed under variable pH and temperature conditions suggested that the differences in the reactivity and activation energy of these compounds are fundamentally attributable to the core nucleophilicity and pKa. Following their screening and mechanistic studies, select lead compounds were further evaluated and demonstrated greater efficacy than Dekon 139 in the topical decontamination of POX in an ex vivo porcine skin model. In addition to OP reactivity, several compounds in the PAM class displayed a dual mode of activity, as they retained the ability to reactivate POX-inhibited acetylcholine esterase (AChE). In summary, this report describes a rationale for the hydrophilic scaffold design of α-nucleophiles, and it offers advanced insights into their chemical reactivity, mechanism, and practical utility as OP decontaminants.
Synthesis of some fluorine-containing pyridinealdoximes of potential use for the treatment of organophosphorus nerve-agent poisoning
Timperley, Christopher M.,Banks, R. Eric,Young, Ian M.,Haszeldine, Robert N.
, p. 541 - 547 (2011/09/15)
Fluoroheterocyclic aldoximes were screened as therapeutic agents for the treatment of anticholinesterase poisoning. 2-Fluoropyridine-3- and -6-aldoxime, and 3-fluoropyridine-2- and -4-aldoxime, were synthesised. Attempts to obtain 3,5,6-trifluoropyridine-2,4-bis(aldoxime) and -2-aldoxime, however, proved unsuccessful. Pentafluorobenzaldoxime was prepared by oximation of pentafluorobenzaldehyde. Acid dissociation constants (pKa) and second-order rate constants (kox-) of the fluorinated pyridinealdoximes towards sarin were measured. 2,3,5,6-Tetrafluoropyridine-4- aldoxime had the best profile: its kox- approached that of the therapeutic oxime P2S (310 vs. 120 l mol-1 min-1), but its higher pKa (9.1 vs. 7.8) fell short of the target figure of 8 required for reactivation of inhibited acetylcholinesterase in vivo. N-alkylation of the fluorinated pyridine-aldoximes may reduce their pK a nearer to 8 and enhance their therapeutic potential. Crown Copyright
