Oxythiamine, an antimetabolite and a vitamin B1 antagonist, is a well-known thiamine antagonist and inhibitor of transketolase. IC50 & Target: Vitamin B1, Thiamine, Transketolase^[1]. In Vitro: Oxythiamine, an antimetabolite and a vitamin B1 antagonist, is a well-known thiamine antagonist and inhibitor of transketolase. Oxythiamine alters protein expression in a dose dependent manner. The level of alpha-enolase is increased by Oxythiamine treatment, while expression of 14-3-3 protein beta/alpha is suppressed by Oxythiamine at a stratified dose. Oxythiamine causes dynamic changes of total protein expression in time dependent fashion. Oxythiamine suppresses expression of cellular phosphor proteins significantly^[2].