Source:http://linkedlifedata.com/resource/umls/id/C1373120
NCI: A substance structurally unlike a nucleoside molecule that is capable of inhibiting the function of a reverse transcriptase. These compounds do not bind to the active site of the polymerase but in a less conserved pocket near the active site, causing a distortion in the shape of the active site and resulting in inhibition of enzymatic function, chain termination, and inhibition of viral replication.