Operculinic Acid Research Articles

樹脂配糖体(第17報)マルバアサガオ地上部のヤラピン, Marubajalapins VIII-XI, の構造について

Four ether-soluble resin glycosidses (jalapins), marubajalapins VIII-XI previously obtained from the aerial part of Pharbitis purturea, were characterized on the basis of chemical and spectral data. All of them and marubajalapin VII reported in the previous paper are mutually positional isomers composed of 3 mol of n-octanoic acid and 1 mol of operculinic acid E having a macrocyclic ester structure.

Resin Glycosides. XI. Operculins III, IV, IX, X, XVI, XVII and XVIII, New Ether-Soluble Resin Glycosides of Rhizoma Jalapae Braziliensis (Root of Ipomoea operculata).

Ten ether-soluble resin glycosides (jalapins), operculins IX-XVIII, were isolated from Rhizoma Jalapae Braziliensis (roots of Ipomoea operculata). Operculins III and IV previously obtained, and operculins IX, X, XVI, XVII and XVIII were characterized on the bases of chemical and spectral data. All of them have a common glycosidic acid, operculinic acid B, with a macrocyclic ester structure and n-decanoyl and/or n-dodecanoyl residues as organic acid groups.

Resin glycosides. IX. Operculins I, II, V, VII and VIII, new ether-soluble resin glycosides of rhizoma Jalapae Braziliensis (the roots of Ipomoea operculata).

Eight ether-soluble resin glycosides (jalapins), operculins I-VIII, were isolated from Phizoma Jalapae Braziliensis (the roots of Ipomoea operculata). Among them, the structures of operculins I, II, V, VII and VIII, which have a common glycosidic acid, operculinic acid A, have been determined on the basis of chemical and spectral data. Similar to the jalapins so far isolated from several Convolvulaceae plants, all of them have intramolecular macrocyclic ester structures. They have n-dodecanoic and/or n-decanoic acid as a component organic acid in place of hitherto known isobutyric, 2-methylbutyric, tiglic and nilic acids.

Operculin I and II, new ether-soluble resin glycosides("Jalapin") with fatty acid ester groups from Rhizoma Jalapae Braziliensis(roots of Ipomoea operculata).

Two new resin glycosides, operculin I and II, were isolated from the ether-soluble fraction (jalapin)[W. Mayer, Justus Libigs Ann. Chem., 83, 121 (1852)] of Rhizoma Jalapae braziliensis, the root of Ipomoea operculata (Convolvulaceae), and their structures have been determined. Both compounds provided on alkaline hydrolysis one identical jalapinolic acid 11-0-glycoside, named operculinic acid A, which forms and intramolecular macrocyclic ester in the parent compounds similarly to the case of analogs isolated from jalapin of all the Convolvulaceae plants so far examined. It is noted, however, that operculin I and II have two moles of a fatty acid, n__--dodecanoic and n__--decanoic acids, respectively, combined at their sugar moiety in place of several organic acids. Accordig to Mosher's method, the absolute configuration at C11 of methyl jalapinolate, which was regarded by Horeau's method as R__-, was shown to be S__-.

Struktur der operculinsäure aus dem harz von Ipomoea operculata

The structure of operculinic acid (rhamnoconvolvulinolic acid), the main glycosidic acid from the ether insoluble resin of Ipomoea operculata has been elucidated as a glucorhamnohexasaccharide of 3,12-dihydroxypalmitic acid mainly by degradative and spectroscopic investigations.