S-
Adenosylhomocysteine (SAH) hydrolase catalyzes the reversible hydrolysis of SAH to adenosine and homocysteine. The inhibition of SAH hydrolase causes the intracellular accumulation of SAH, elevating the ratio of SAH to S-
adenosylmethionine (SAM) and inhibiting SAM-
dependent methyltransferase. (−)-
Neplanocin A potently and irreversibly inactivates SAH hydrolase (K
i = 8.39 nM).
1 It has antitumor activity against mouse leukemia L1210 cells and broad-
spectrum antiviral activity.
2,3,4,1 Neplanocin A is more potent against vesicular stomatitis than the reversible SAH hydrolase inhibitor 3-
deazaneplanocin (ID
50 = 0.07 and 0.3 μg/ml, respectively).
3,5 
