10.1016/j.bmcl.2004.09.050
The research aimed to develop new inhibitors targeting the hydrolytic activity of S-adenosylhomocysteine (AdoHcy) hydrolase, an enzyme crucial in the regulation of biological methylation reactions, with potential applications in antiviral, antiparasitic, immunosuppressive, and plasma homocysteine-lowering agents. The study focused on a series of haloethyl and dihalocyclopropyl esters derived from homoadenosine-60-carboxylic acid, which were designed to interact with the enzyme. The researchers found that incubation of these esters with the enzyme led to time- and concentration-dependent inactivation of AdoHcy hydrolase and a significant depletion of its NAD+ content. The inactivation was irreversible and was attributed to the enzyme's oxidative activity rather than its hydrolytic activity. The chemicals used in the process included haloethyl esters (2a and 2b) and dihalocyclopropyl esters (3a and 3b), with the dihalocyclopropyl esters showing higher affinity and lower kinact values compared to the haloethyl esters. The study concluded that these esters inactivate AdoHcy hydrolase through a type I mechanism, involving the oxidative activity of the enzyme, rather than acting as substrates for its hydrolytic activity.