ABSTRACT
Phytochemical investigation of the stems from Brucea javanica led to the isolation of two new quassinoids, brujavanol C (1) and brujavanol D (2), together with six known compounds (3-8). The chemical structures were elucidated by means of various spectroscopic methods. All the isolated compounds were evaluated for antimalarial activity against Plasmodium falciparum and compounds 6 and 7 exhibited the most potent activity against the K1 strain, with IC50 values of 1.41 and 1.06 µM, respectively.
Subject(s)
Antimalarials/pharmacology , Brucea/chemistry , Malaria/parasitology , Plant Extracts/pharmacology , Plasmodium falciparum/drug effects , Quassins/pharmacology , Antimalarials/chemistry , Antimalarials/isolation & purification , Molecular Structure , Plant Extracts/chemistry , Plant Stems/chemistry , Plasmodium falciparum/growth & development , Quassins/chemistry , Quassins/isolation & purificationABSTRACT
Biotranformation of ent-kaur-16-en-19-oic acid (1) using Psilocybe cubensis resulted in hydroxylated products. After two days of incubation, ent-16beta,17-dihydroxy-kauran-19-oic acid (2) was isolated. After further incubation for nine days, two novel metabolites, ent-12alpha,16beta,17-trihydroxy-kauran-19-oic acid (3) and ent-11alpha,16beta,17-trihydroxy-kauran-19-oic acid (4), were obtained. The metabolites were identified by spectroscopic methods and X-ray crystallography. Compounds 1-4 were evaluated for their cytotoxic properties against the human leukaemia K562 cell line; only compound 1 showed moderate activity.