The present invention relates to a method of modulating pluripotency and/or self-renewing characteristics of a stem/progenitor cell. The method comprises administering to the respective cell a compound of the general formula (I) In the general formula A is C or N. R1, R4 and R5 are, independently selected, H or aliphatic, cycloaliphatic, aromatic, arylaliphatic, or arylcycloaliphatic hydrocarbyl groups, that comprise 0-3 heteroatoms being N, O, S, or Si. R4 and R5 may optionally be linked so as to define an aliphatic hydrocarbyl bridge. R2 is H or a halogen. R3 is H, or an aliphatic or arylaliphatic hydrocarbyl group comprising 1-8 main chain carbon atoms and 0-3 heteroatoms being N, O, S, Si, or a halogen.