| abstract |
Compounds of the formula I <IMAGE> (I) in which R1 is lower alk-2-en-1-yl, lower alk-3-en-2-yl, lower alk-2-yn-1-yl or lower alkyl substituted in the 2,3-position by radicals which can be eliminated to give a double bond, R2 is hydrogen and R3 is methyl which is unsubstituted or substituted by radicals which can be eliminated together with hydrogen R2 to give a double bond or R2 and R3 are both hydrogen or lower alkyl or are together methylene and R4 is a group of the formula Ia, Ib or Ic <IMAGE> (Ia) <IMAGE> (Ib) <IMAGE> (Ic) in which R5 is hydrogen, lower alkyl, lower alk-2-en-1-yl or lower alk-2-yn-1-yl and R6 is a group of the formula Id or Ie <IMAGE> (Id) <IMAGE> (Ie) in which R1, R2, R3 and R5 are as defined, and their pharmaceutically acceptable salts can be used in a novel manner for the treatment of diseases of the rheumatoid type. |