Extraction of the ground leaves (2 kg) was carried out in the usual
manner by partitioning the concentrated EtOH extract with dilute acid which has been described in detail
elsewhere (19,20) to give a total crude alkaloid yield ofca. 3.5 gkg-’. The alkaloids were isolated by initial
cc on Si gel using CHCI, with increasing MeOH gradient followed by rechromatography of appropriate
partially resolved fractions (solvent systems: CHCI, with increasing MeOH gradient, Et,O and Et,O with
increasing EtOAc gradient) and finally preparative tlc on Si gel [solvent system hexane-EtOAc (3:7)1. The
yields (gekg-’) of the alkaloids isolated were as follows: voacangine (0.13), voacristine (0.87), voacristine-
7-hydroxyindolenine (0.01 3), apparicine (0.0043), 19-epi-voacristine (0.087), conophylline 111 (0.65), and
conophyllidine E21
Extraction of the ground leaves (2 kg) was carried out in the usualmanner by partitioning the concentrated EtOH extract with dilute acid which has been described in detailelsewhere (19,20) to give a total crude alkaloid yield ofca. 3.5 gkg-’. The alkaloids were isolated by initialcc on Si gel using CHCI, with increasing MeOH gradient followed by rechromatography of appropriatepartially resolved fractions (solvent systems: CHCI, with increasing MeOH gradient, Et,O and Et,O withincreasing EtOAc gradient) and finally preparative tlc on Si gel [solvent system hexane-EtOAc (3:7)1. Theyields (gekg-’) of the alkaloids isolated were as follows: voacangine (0.13), voacristine (0.87), voacristine-7-hydroxyindolenine (0.01 3), apparicine (0.0043), 19-epi-voacristine (0.087), conophylline 111 (0.65), andconophyllidine E21
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