Abstract Prodrugs of the two opiate antagonists naloxone and naltrexone, in particular the 3- monophosphate, 3-triphosphate, 3-monosulfate and 3, 14-disulfate esters, have been synthesized and evaluated for: i) their ability to bind opioid receptors in vitro; and ii) their stability in both space and time upon entrapment into ex vivo human red blood cells (RBC). We find that, unlike the other esters, the mono-and triphosphate esters of naloxone and ...
