1.3.8- Trihydroxy-7-methylanthraquinone

Trihydroxy-2-methylanthraquinone. See Aloeemodine A140-R 4 ,5,7-Trihydroxy-2-phenylchromone. See Apigenin A473-R... 

Emodin (l,6,8-trihydroxy-3-methylanthraquinone), the active principle of Polygonum cuspidatum (Polygonaceae), was reported to be an inhibitor of the p56 -PTK activity from bovine thymus, with an IC50 of 18.5 pM. When the hydroxyl functions at C-6 or C-8 were blocked by methylation or glycosylation, respectively, the effect disappeared. The inhibition was competitive with respect to ATP and non competitive with respect to the substrate [64]. In a bioassay-guided separation of the anthraquinones found in rhizomes of another Polygonaceae species, rhubarb Rheum... 

Synonym 1,3,8-Trihydroxy-6-methylanthraquinone Source Stahl, E. Schilz, W. Schutz, E. Willing, E. Angew. Chem. Int. Ed. Engl. (1978), 17, 731-738. 

Various organic reagents are used for direct determination of calcium, such as murexide (ammonium purpurate) (e = 1.4-10 at 500 nm) [2,49], Metalphthalein [50], Calcein [51,52], Chrome Azurol S (in the presence of 1,10-phenanthroline) [53], Alizarin S [54], 8-hydroxyquinoline (extraction into CHCI3 in the presence of n-butylamine or butoxyethanol) [55], and Emodine (l,3,8-trihydroxy-6-methylanthraquinone) [56]. Calcium has been determined as a complex with Emodine, in the presence of Be and Mg, by the derivative spectrophotometry technique. The anionic complexes of calcium with bromo-oxine [57] or HTTA [58] have been extracted into benzene as ion associates with Rhodamine B. Calcium was also determined as a complex with o-cresolphthalein [59-63], or thymolphthalein [64]. 

Geranyl-l,3,8-trihydroxy-6-methylanthraquinone, G-20021 2-Geranyl-l,3,7-trihydroxy-4-prenylxanthone, G-30015... 

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