70147-59-0Relevant articles and documents
Nucleic acid related compounds. 101. S-adenosyl-L-homocysteine hydrolase does not hydrate (5'-fluoro)vinyl or (6'-halo)homovinyl analogues derived from 3'-deoxyadenosine or 3'-(chloro or fluoro)-3'-deoxyadenosine
Robins,Neschadimenko,Ro,Yuan,Borchardt,Wnuk
, p. 1205 - 1211 (1998)
S-Adenosyl-L-homocysteine (AdoHcy) hydrolase is crucial for the maintenance of biomethylation. The usual mechanistic sequence involves oxidation of AdoHcy at C3' followed by elimination of L-homocysteine, Michael addition of water, and reduction to give adenosine. A 6'- fluorohomovinyladenosine analogue (EDDFHA) undergoes hydration of the 5',6' double bond (hydrolytic activity) at a more rapid rate than oxidation at C3'. Three 4',5'-didehydro-5'-deoxy-5'-fluoro nucleoside analogues were prepared from 3'-deoxy- and 3'-(chloro and flouro)-3'-deoxyadenosine via generation of the vinyl fluorides by thermolysis of 5'-fluoro-5'-thioether sulfoxides. The 3'-deoxy analogues of 6'-halohomovinyladenosines were prepared by Wittig extension with a 3'-deoxy-5'-carboxaldehyde and halodestannylation of vinyl stannanes. The 3'-hydroxyl group appears to be essential for binding to AdoHcy hydrolase. No hydrolytic activity at C5', or C6' was observed with the nonoxidizable 3'-deoxy or 3'-(chloro or fluoro) analogues in contrast with their 3'-hydroxy counterparts (ZDDFA and EDDFHA). These 3'-modified analogues cannot reduce enzyme-bound NAD+ to NADH and do not produce time-dependent inhibition for AdoHcy hydrolase, but are weak competitive inhibitors (K(i) = 150-200 μM).