RESUMO
Bioassay-guided fractionation of the methanol extracts of the aerial parts of Psychotria uliginosa Sw yielded four known bioactive compounds: benz[g]isoquinoline-5,10-dione and 1-hydroxy-4,7-megastigmadien-3-one and blumenol A, which are chemically related to S-(+)-dehydrovomifoliol a known inhibitor of the germination of lettuce seeds. Evaluation of the basic components obtained from the methanol extract of the aerial parts of Psychotria bahiensis DC. yielded five bioactive indole monoterpenoid alkaloids which are known to display various levels of antiplasmodial and antitumor activity: 5 alpha-carboxystrictosidine, angustine, strictosamide and (E) and (Z)-vallesiachotamine; and the novel epimers bahienoside A and B which are currently being investigated for biological activity. The structures were determined by means of 1D and 2D NMR techniques