Alcaloides indólicos de cascas de Aspidosperma vargasii E A. desmanthum

Fractionation of extracts resulted in isolation and identification of indole alkaloids ellipticine and N-methylteti:ahydroellipticine from. A. vargasii and aspidocarpine from A. desmanthum. Identification of these compounds was achieved based on IR, MS, 1H, 13C and 2-D NMR data and comparison to data in the literature

Chemical constituents isolated from twigs and barks of amapazeiro (Parahancornia amapa, Apocynaceae)

Parahancornia amapa (Apocynaceae) is typical of the Amazon region and popularly known as amapazeiro and widely used in folk medicine in the Amazon region. The objective of this work was to study the phytochemical composition of twigs and barks of this species. From the dichloromethane extract of twigs were isolated β-sitosterol, stigmasterol, and pentacyclic triterpenoids α-amyrin, β-amyrin, lupeol and friedelin. From the methanol extract of barks was isolated indole alkaloid isositsiriquina. The structures of these compounds were identified by analysis of the mass spectra high-resolution, ¹H and 13C NMR and comparisons with literature data. This is the first report of isolation of alkaloid in this genus.Parahancornia amapa (Apocynaceae) é típica da região amazônica e conhecida popularmente como amapazeiro e muito utilizada na medicina popular da região Amazônica. O objetivo desse trabalho foi o estudo fitoquímico dos galhos e cascas dessa espécie. Do extrato diclorometânico dos galhos foram isolados o β-sitosterol, estigmasterol, além de triterpenóides pentacíclicos, α-amirina, β-amirina, lupeol e friedelina. Do extrato metanólico das cascas foi isolado o alcaloide indólico isositsiriquina. As estruturas desses compostos foram identificadas por análise dos espectros de massa de alta resolução, Ressonância Magnética Nuclear de ¹H e 13C e comparações com dados da literatura. Esse é o primeiro relato de isolamento de alcaloide neste gênero

In vitro inhibition of Plasmodium falciparum by substances isolated from Amazonian antimalarial plants

In the present study, a quassinoid, neosergeolide, isolated from the roots and stems of Picrolemma sprucei (Simaroubaceae), the indole alkaloids ellipticine and aspidocarpine, isolated from the bark of Aspidosperma vargasii and A. desmanthum (Apocynaceae), respectively, and 4-nerolidylcatechol, isolated from the roots of Pothomorphe peltata (Piperaceae), all presented significant in vitro inhibition (more active than quinine and chloroquine) of the multi-drug resistant K1 strain of Plasmodium falciparum. Neosergeolide presented activity in the nanomolar range. This is the first report on the antimalarial activity of these known, natural compounds. This is also the first report on the isolation of aspidocarpine from A. desmanthum. These compounds are good candidates for pre-clinical tests as novel lead structures with the aim of finding new antimalarial prototypes and lend support to the traditional use of the plants from which these compounds are derived