The present invention relates to a compound according to formula (I)or pharmaceutically acceptable salts, hydrates, or solvates thereof; wherein R1 is C1-alkyl, R2 is C1-alkyl, R3 is C2-alkyl, R4 is hydrogen, R5 is hydrogen. The invention relates further to said compounds for use in therapy, to pharmaceutical compositions comprising said compounds, to said compounds for use in the treatment autoimmune diseases and to intermediates for the preparation of said compounds.