8174. Rhapontin

Nomenclature

CAS number: 155-58-8
(E)-3-Hydroxy-5-[2-(3-hydroxy-4-methoxyphenyl)ethenyl]phenyl β-d-glucopyranoside; 4′-methoxy-3,3′,5-stilbenetriol 3-glucoside; rhaponticin; ponticin.
C21H24O9; mol wt 420.41.
C 59.99%, H 5.75%, O 34.25%.

Description and references

From root of Rheum rhaponticum L., Polygonaceae: Hesse, J. Prakt. Chem. 77, 321 (1908); Schürhoff, Plettner, Arch. Pharm. 275, 281 (1937). On hydrolysis yields rhapontigenin and glucose: Kawamura, J. Pharm. Soc. Jpn. 58, 405 (1938), C.A. 32, 66554 (1938). Constitution of rhapontigenin: Takaoka, Proc. Imp. Acad. Tokyo 16, 408 (1940), C.A. 35, 13992 (1941).

Chemical structure

Properties

Crystals, dec 236-237°. [α]D32 -59.5° (acetone). Exhibits bright blue fluorescence. Sol in dil alcohol, hot acetone, hot water; slightly sol in ether, alc, acetone, cold water; practically insol in benzene, petr ether, chloroform.