retinoids with a derivatized terminal carboxyl group were significantly less active than all-trans-retinoic acid , and those with the addition of two methyl groups to the cyclohexenyl ring of retinoic acid or substitution of its beta-cyclogeranylidene group with a 1,1,3,3-5-indanyl ring system were markedly more active than all-trans-retinoic acid .
C0035339
retinoids
C0040845
trans-retinoic