The efficient and affordable regioselective methods for the synthesis of vinyl sulfones. These methods allow for the study of structure-activity relationships of various analogs of 4-methyl-N- S -1-oxo-3-phenyl-1- S,E -5-phenyl-1- phenylsulfonyl pent-1-en-3-yl amino propan-2-yl piperazine-1-carboxamide K777 . Vinyl sulfones obtained from the methods described may be useful in organic synthesis of sulfur-containing compounds. Compounds prepared by the methods described may be useful for the treatment of cancers and infectious diseases including Chagas’ disease, as well as other diseases caused by an infection of a parasite of the genus Trypanosoma. Compounds prepared by the methods described may also be useful for treatments requiring the inhibition of polo-like kinase 1 PLK1 , MAP kinases and cysteine proteases.