Target-Guided Isolation of O-tigloylcyclovirobuxeine -B from Buxus sempervirens L. by Centrifugal Partition Chromatography

The increasing drug resistance of malaria parasites challenges the treatment of this life-threatening disease. Consequently, the development of innovative and effective antimalarial drugs is inevitable. O-tigloylcyclovirobuxeine-B, a nor-cycloartane alkaloid from Buxussempervirens L., has shown promising and selective in vitro activity in previous studies against Plasmodiumfalciparum (Pf), causative agent of Malaria tropica. For further investigations, it is indispensable to develop an advanced and efficient isolation procedure of this valuable natural product. Accordingly, we used liquid-liquid chromatography including centrifugal partition chromatography (CPC) to obtain the pure alkaloid on a semi-preparative scale. Identification and characterization of the target compound was accomplished by UHPLC/+ESI-QqTOF-MS/MS, ¹H NMR and ¹³C NMR. In conclusion, this work provides a new and efficient method to obtain O-tigloylcyclovirobuxeine-B, a valuable natural product, as a promising antiplasmodial lead structure for the development of innovative and safe medicinal agents.

Keywords: Buxus sempervirens L.; O-tigloylcyclovirobuxeine-B; antimalarial activity; centrifugal partition chromatography; nor-cycloartane alkaloids; target-guided isolation.