| abstract |
Immunosuppressive cyclolignan derivatives are provided of formula (I) or (II):n n orn n in which R¹ is hydrogen, hydroxy, alkoxy; R and R³ are hydrogen, alkyl, acyl, or together R and R³ form a group -CHR⁴-; R⁴ is hydrogen, alkyl, alkenyl, hydroxyalkyl, (poly)haloalkyl, aryl, acyloxyalkyl, alkoxy, carboxyalkyl, alkoxycarbonyl, carbamoyl; R⁵ when present is hydrogen, alkyl, alkenyl, aryl, (poly)haloalkyl, acyl, carbamoyl, or thiocarbamoyl; R⁶ is alkyl, hydroxyalkyl, haloalkyl, acyl, acyloxyalkyl, carboxy or alkoxycarbonyl; Ar is 3,4,5-trialkoxyphenyl or 4-hydroxy-3,5-dialkoxyphenyl; and X is nitrogen or oxygen. |