Chemoenzymatic synthesis of analogues of the second messenger candidate cyclic adenosine 5′-diphosphate ribose

A broad substrate specificity for adenosine 5′-diphosphate ribosyl cyclase is demonstrated by cyclisation of ribose-and purine-modified nicotinamide adenine dinucleotide analogues to mimics of cyclic adenosine 5′-diphosphate ribose, generating a straightforward route for structural modification of this important Ca2+-mobilising nucleotide.