– 5′-chloro-5′-Deoxyadenosine (hydrate) is a nucleoside analog used as a substrate in polyketide biosynthesis. S-(5′-adenosyl)-L-methionine can be converted to 5′-chloro-5′-deoxyadenosine in a reaction catalyzed by a SAM-dependent chlorinase. Through a 7-step route, 5′-chloro-5′-deoxyadenosine can be converted to chloroethylmalonyl-CoA, which has been shown to be involved in the biosynthesis of the anticancer agent salinosporamide A in the marine bacterium S. tropica.