Card-20(22)-enolide, 3-[(O--d-glucopyranosyl-(1®4)-O-2,6-dideoxy--d-ribo-hexopyranosyl-(1®4)-O-2,6-dideoxy--d-ribo-hexopyranosyl-(1®4)-2,6-dideoxy--d-ribo-hexopyranosyl)oxy]-12,14-dihydroxy-, (3,5,12)-.
Deacetyllanatoside C [17598-65-1].
» Deslanoside contains not less than 95.0 percent and not more than 103.0 percent of C47H74O19, calculated on the dried basis.
CautionHandle Deslanoside with exceptional care, since it is highly potent.
Packaging and storage Preserve in tight, light-resistant containers. Store at 25, excursions permitted between 15 and 30.
Identification Prepare a solution of it in methanol containing about 4 mg per mL. Apply 5 µL of this solution and 5 µL of a methanol solution of USP Deslanoside RS containing 4 mg per mL to a suitable thin-layer chromatographic plate coated with a 0.25-mm layer of chromatographic silica gel. Allow the spots to dry, and develop the chromatogram in a solvent system consisting of a mixture of methylene chloride, methanol, and water (130:36:3) until the solvent front has moved about three-fourths of the length of the plate. Remove the plate from the developing chamber, mark the solvent front, and allow the solvent to evaporate. Locate the spots on the plate by lightly spraying with dilute perchloric acid (1 in 20) and heating at about 100 for 3 minutes. Cool, and examine under UV light: the RF value of the principal spot obtained from the test solution corresponds to that obtained from the Standard solution.
Specific rotation 781S: between +7.0 and +8.5.
Test solution: 20 mg per mL, in anhydrous pyridine.
Loss on drying 731 Dry 0.5 g in vacuum at 100 to constant weight: it loses not more than 5.0% of its weight.
Residue on ignition 281: not more than 0.2%.
Standard preparation Dissolve a suitable quantity of USP Deslanoside RS in alcohol, and quantitatively dilute with alcohol to obtain a solution having a known concentration of about 200 µg per mL.
Assay preparation Transfer about 20 mg of Deslanoside, accurately weighed, to a 100-mL volumetric flask, dissolve in and dilute with alcohol to volume, and mix.
Procedure Transfer 3.0 mL each of the Standard preparation, the Assay preparation, and alcohol to provide the blank, to separate 25-mL conical flasks. Evaporate each with gentle warming and with the aid of a current of air just to dryness, and cool in a vacuum desiccator for 30 minutes. Add 15.0 mL of acid-ferric chloride TS to each flask, mix by swirling, and allow the mixtures to stand protected from light, swirling frequently, at a temperature not exceeding 30, for 15 minutes. Pass each through separate fine glass wool filters. Concomitantly determine the absorbances of the solutions in 1-cm cells at the wavelength of maximum absorbance at about 590 nm, with a suitable spectrophotometer, using the blank to set the instrument. Repeat the measurements at 2-minute intervals until maximum absorbance readings have been obtained. Calculate the quantity, in mg, of C47H74O19 in the Deslanoside taken by the formula:
0.1C(AU / AS)in which C is the concentration, in µg per mL, of USP Deslanoside RS in the Standard preparation; and AU and AS are the maximum absorbances of the solutions from the Assay preparation and the Standard preparation, respectively.
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USP32NF27 Page 2074Pharmacopeial Forum: Volume No. 29(5) Page 1448