The document reports the Ki and Ki* values for various inhibitors of two methyltransferase enzymes, HpMTAN and SaMTAN. Ki is the inhibition constant and Ki* is the inhibition constant of time-dependent inactivation. For both enzymes, the best inhibitors were PT03-159, DHL-159, and PCLMT-O-A, with Ki values in the low nanomolar range. The para-substituted analogues generally had higher Ki values than the meta-substituted analogues.