1,N⁶-Ethenoadenosine；

Nucleosides are magic molecules for drug discovery. Nucleosides are the small pieces from DNA and RNA in our body. Therefore, nucleosides come from body with some modification for special purposes. Body tends not to against nucleosides because they are so close (like) with millions of pieces in our body. Therefore, screening nucleosides gives the highest hitting rate (rate to find active compounds), and may be thousands of times higher than general small heterocyclic compounds (body does not like those strange molecules). Therefore, nucleoside drug candidates would have less problem on PK, PD and toxicity which are the key considerations for drug discovery and development.