3156. Diginatin

Nomenclature

CAS number: 52589-12-5
(3β,5β,12β,16β)-3-[(O-2,6-Dideoxy-β-d-ribo-hexopyranosyl-(1→4)-O-2,6-dideoxy-β-d-ribo-hexopyranosyl-(1→4)-2,6-dideoxy-β-d-ribo-hexopyranosyl)oxy]-12,14,16-trihydroxy-card-20(22)-enolide.
C41H64O15; mol wt 796.94.
C 61.79%, H 8.09%, O 30.11%.

Description and references

Cardiac glycoside from Digitalis lanata Ehrk., Scrophulariaceae: Murphy, J. Am. Pharm. Assoc. Sci. Ed. 44, 719 (1955); Angliker et al., Ann. 607, 131 (1957); von Wartburg et al., Experientia 14, 439 (1958). Acid hydrolysis yields 1 mol diginatigenin + 3 mols d-digitoxose. The sugar residue is attached to the hydroxyl group at C-3 of the aglycon.

Properties

Prisms from acetone, mp 251-253°. Somewhat hygroscopic. [α]D20 +20.5 ±2°; [α]20546 +26.3 ±2° (c = 0.6 in methanol). Absorption max (98% w/w H2SO4): 230, 310, 390, 480, 560 nm (E1%1cm 185, 175, 315, 230, 120). Sol in alcohol, dil alcohol, dioxane; slightly sol in acetone. One part sol in 1000 parts water and in 2000 parts chloroform at 25°.

Derivative

Acetyldiginatin-α.
C43H66O16; mol wt 838.97.
C 61.56%, H 7.93%, O 30.51%.

Properties

Flat plates from methanol + chloroform+ ether, mp 199-202°. [α]D20 +30.1° (c = 0.6 in pyridine). uv max: 218 nm (log ε 4.1).