Identification and characterization of organic and glycosidic acids in crude resin glycoside fraction from Calystegia hederacea

A New Glycosidic Acid, Muricatic Acid D, and Resin Glycosides, Muricatins X and XI, from the Crude Resin Glycoside Fraction of the Seeds of <i>Ipomoea muricata</i>

“…The alkaline hydrolysis of 2 yielded 2-methylbutyric acid and scammonic acid A (11a). 17) The 1 H-and 13 C-NMR spectra of 2 were superimposable on those of 1, except for the appearance of signals due to the terminal β-D-quinovopyranosyl residue and the absence of the signals due to the terminal β-Dfucopyranosyl residue (Tables 1, 2). The HMBC spectrum of 2 also exhibited key correlations between H-3 of Glc and C-1 of Jla and between H-2 of Rha and C-1 of Mba.…”

“…The glycosidic acids derived from 1 and 2 were identical with 10a and scammonic acid A (11a), respectively, by comparison of 1 H-NMR data with those of authentic sample or those already reported. 17) Alkaline Hydrolysis of the Crude Resin Glycoside Fraction A part (2.03 g) of the crude resin glycoside fr. 6) was dissolved in 1 M KOH-1,4-dioxane (9 : 1, 10 mL) and heated at 95 °C for 1 h. After cooling, the reaction mixture was adjusted to pH 4 with 1 M HCl and shaken with ether (10 mL × 5).…”

“…The t R of 5 (24.54 min) was in better agreement with that (24.61 min) of p-bromophenacyl 2S,3S-nilate 8) rather than that (26.01 min) of p-bromophenacyl 2R,3R-nilate. 18) Acidic Hydrolysis of the Glycosidic Acid Fraction from the Crude Resin Glycoside Fraction A part (99 mg) of the glycosidic acid fr. in 1 M HCl (2 mL) was heated at 95 °C for 1 h. The reaction mixture was diluted with H 2 O (5 mL) and then extracted with ether (5 mL × 6).…”

Chemistry and biological activity of resin glycosides from Convolvulaceae species

“…A new glycosidic acids, calyhedic acid A ( 66 ), was isolated from the alkaline hydrolysis product of the crude resin glycoside fraction of the Calystegia hederacea whole plants 69 . The structure is defined as 12 S ‐hydroxyhexadecanoic acid 12‐ O ‐α‐ l ‐rhamnopyranosyl‐(1→2)‐ O ‐[ β ‐ d ‐glucopyranosyl‐(1→6)‐ O ‐ β ‐ d ‐glucopyranosyl‐(1→3)]‐ O ‐ β ‐ d ‐glucopyranosyl‐(1→2)‐ O ‐ β ‐ D ‐quinovopyranoside.…”

“…Calyhedic acids C ( 257 ) and D ( 258 ) were obtained from the alkaline hydrolysis product of the crude resin glycoside fraction of C. hederacea whole plants 69 . The structure of calyhedic acid C ( 257 ) was determined to be 11 S ‐hydroxyhexadecanoic acid 11‐ O ‐ β ‐ d ‐glucopyranosyl‐(1→3)‐ O ‐ α ‐ l ‐rhamnopyranosyl‐(1→2)‐ O ‐[ β ‐ d ‐glucopyranosyl‐(1→6)‐ O ‐ β ‐ d ‐glucopyranosyl‐(1→6)‐ O ‐ β ‐ d ‐glucopyranosyl‐(1→3)]‐ O ‐ β ‐ d ‐glucopyranosyl‐(1→2)‐ O ‐ β ‐ d ‐quinovopyranoside, and calyhedic acid D ( 258 ) is an isomer of calyhedic acid C ( 257 ) where the 11 S ‐hydroxyhexadecanoyl residue was replaced by a 12 S ‐hydroxyhexadecanoyl residue.…”