Structure-activity relationships of anthraquinones in the decrease of intestinal motility.
The effects of substituted anthraquinones on intestinal motility were evaluated in-vitro using rabbit small intestinal strips. This structure-activity relationship study revealed the critical requirement of a hydroxy group at R2 position. The intestinal motility was inhibited 50% (IC50) by emodine (8 microM), 2-hydroxy anthraquinone (20 microM), 2,6-dihydroxy anthraquinone (25 microM), 2,7-dihydroxy anthraquinone (10 microM), 1,2,4-trihydroxy anthraquinone (80 microM) and 1,2,5,8-tetra-hydroxyanthraquinone (9 microM). The presence of other polar groups at R2 position such as an amino, aldehyde and carboxylic acid group significantly reduced the activity (IC50 360-400 microM). The presence of a methyl group and esterification of the carboxylic acid at R2 position was found to abolish the activity. These data are useful for the future development of anthraquinones as laxative agents.
Department of Pharmacy, Tajen Junior College of Pharmacy, Ping Tung, Taiwan.
D H
DH
Kuo
S C
SC
Kuo
J T
JT
Cheng
D000818:Animals; D000880:Anthraquinones / Q000737:chemistry / Q000494:pharmacology*; D002400:Cathartics / Q000737:chemistry / Q000494:pharmacology*; D005769:Gastrointestinal Motility / Q000187:drug effects*; D066298:In Vitro Techniques; D008297:Male; D011817:Rabbits; D013329:Structure-Activity Relationship
D000880:Anthraquinones; D002400:Cathartics