| 摘要 |
<p>10/11 Bromo 14,15 dihydro 14-beta hydroxy (3alpha,16alpha) eburnamine 14-carboxylic acid methyl ester of formula (I) is made by (a) reaction of a mixt. of 14,15-dihydro 14 alpha/beta -hydroxy (3alpha,16alpha) eburnamenine 14-carboxylic acid methyl ester with a soln. of bromine in a halogenated organic solvent, e.g. CHCl3, in presence of a Lewis acid, e.g. FeCl3.6H2O, as catalyst at 0 deg.C; and (b) addn. of a base to alkaline pH and extraction of the alkaloids, which are purified by conventional methods.</p> |
