SAR around ( l)- S-adenosyl- l-homocysteine, an inhibitor of human DNA methyltransferase (DNMT) enzymes

The inhibitory activity of base-modified SAH analogues and the specificity for binding to human DNMT1 and DNMT3b2 enzymes was explored. The 6-amino group was essential while the 7-N of the adenine ring of SAH could be replaced by CH– without loss of activity against both enzymes. The introduction of small groups at the 2-position of the adenine moiety favors DNMT1 over DNMT3b2 inhibition whereas alkylation of the N 6-amino moiety favors the inhibition of DNMT3b2 enzyme. The inhibitory activity of base-modified SAH analogues and the specificity of inhibiting human DNMT1 and DNMT3b2 enzymes was explored. The 6-amino group was essential while the 7-N of the adenine ring of SAH could be replaced by CH– without loss of activity against both enzymes. The introduction of small groups at the 2-position of the adenine moiety favors DNMT1 over DNMT3b2 inhibition whereas alkylation of the N 6-amino moiety favors the inhibition of DNMT3b2 enzyme.