Nanaomycin A. It apparently has stronger DMNT1 inhibition than 5-aza.
"Moreover, nanaomycin A showed reduced global methylation levels in all three cell lines when tested at concentrations ranging from 0.5 to 5 μM. Nanaomycin A reactivated the transcription of the RASSF1A tumor suppressor gene inducing its expression up to 18-fold at 5 μM, higher than the reference drug 5-azacytidine (sixfold at 25 μM). "