2818. Daphnin

Nomenclature

CAS number: 486-55-5
7-β-d-Glucopyranosyloxy-8-hydroxy-2H-1-benzopyran-2-one; 7,8-dihydroxycoumarin 7-β-d-glucoside; daphnetin 7-β-d-glucoside; 7-glucosido-8-hydroxycoumarin.
C15H16O9; mol wt 340.28.
C 52.94%, H 4.74%, O 42.32%.

Description and references

In bark and flower of Daphne spp. Extraction from fresh bark of D. mezereum L., Thymelaeaceae: Beilstein XXXI, 248. Structure: Wessely, Sturm, Ber. 63, 1299 (1930); Hattori, Chem. Zentralbl. 1930 II, 2138. Synthesis: Gandini, Gazz. Chim. Ital. 70, 611 (1940), C.A. 35, 1394 (1941).

Chemical structure

Properties

Monohydrate, prisms from water. Anhydr after drying at 80-90° at 2 mm Hg. When anhydrous, dec 215° (Wessely, Sturm); dec 224° (Hattori); dec 229° (older data). Optical rotations of monohydrate: [α]D22 -124° (15 mg in 4 ml MeOH); after 2 recrystns from water: [α]D22 -115° (abs MeOH) (Wessely, Sturm); [α]D15 -84.2° (MeOH) (Hattori). Sol in hot water, alcohol; sol in aq solns of alkalies and alkali carbonates with yellow color. Insol in ether. Hydrolyzed by dilute acid yielding 7,8-dihydroxycoumarin and d-glucose. Also split by emulsin.