Rhoeadine

BeschreibungThis alkaloid was found by Hesse in Papaver rhoeas Linn (red poppy) and its reputed existence in opium now appears doubtful. The base crystallizes from a mixture of CHCl3 and Et20 and sublimes at 21 5-225°C/0.02 mm. It has [α]17.5D + 232° (CHCI 3) or [α]19D + 243° (CHCl3). It behaves as a weak base and is sparingly soluble in H20, alkaline solutions and most organic solvents. It dissolves in mineral acids giving an intensely red solution but investigation shows that only a small proportion of the alkaloid is used to produce the colour, the major part being converted into a colourless, crystalline substance, Rhoeagenine, a much stronger base, non-volatile, and stable to acids. This base is not isomeric with the alkaloid as first thought but has the formula C2oH1906N, m.p. 236-8°C; [α]19D + l68° (AcOH).). Rhoeadine itself contains two methylenedioxy groups, one methoxy group and an N-methyl group. The salts are not easy to prepare but a crystalline hydriodide dihydrate is formed by addition of KI to a solution of the alkaloid in AcOH. The ultraviolet spectrum of the alkaloid shows absorption maxima at 205, 240 and 292 mμ.

VerwendenAs an isoquinoline alkaloid, Rhoeadine can be used in the therapeutic field particularly for the prevention and the treatment of pathologies implying a central and/or peripheral disorder.