14 research outputs found
Chemical constituents from Aspidosperma illustre (Apocynaceae)
A new natural product oleanane-type triterpene, olean-12-ene-11α-methoxy-3β-acetate (10) was isolated from Aspidosperma illustre, together with β-amyrin (3), lupeol (4), β-amyrin acetate (5), lupeol acetate (6), olean-12-ene-28-hydroxy-3β-tetradecanoate (7), olean-12-ene-28-carboxy-3β-hexadecanoate (8), ursolic acid (9) triterpenes, and two monoterpenic indole alkaloids, β-yoimbine (1) and 1,2-dehydroaspidospermidine (2). These compounds were characterized on their spectral data basis, mainly one- (¹H, 13C, APT) and two-dimensional (¹H-¹H-COSY, ¹H-¹H-NOESY, HMQC and HMBC) NMR, and mass spectra, involving also comparison with data from the literature
Application of Preparative High-Speed Counter-Current Chromatography for the Separation of Two Alkaloids from the Roots of Tabernaemontana catharinensis (Apocynaceae)
Other compounds isolated from Simira glaziovii and the ¹H and 13C NMR chemical shift assignments of new 1-epi-castanopsol
A new triterpene, 1-epi-castanopsol, besides eleven known compounds: sitosterol, stigmasterol, campesterol, lupeol, lupenone, simirane B, syringaresinol, scopoletin, isofraxidin, 6,7,8-trimethoxycoumarin and harman, were isolated from the wood of Simira glaziovii. The structures of the known compounds were defined by 1D, 2D ¹H, 13C NMR spectra data analyses and comparison with literature data. The detailed spectral data analyses allowed the definition of the structure of the new 1-epi isomer of castanopsol and performance of ¹H and 13C NMR chemical shift assignments
Spruceanumines A and B, novel plumeran indole alkaloids from Aspidosperma spruceanum(Apocynaceae)
Two novel indole alkaloids with plumeran skeleton, spruceanumines A (1) and B (2), and eight known indole alkaloids, aspidospermidine (3), demethoxypalosine (4), aspidocarpine (5), aspidolimine (6), fendlerine (7), aspidolimidine (8), obscurinervidine (9) and obscurinervine (10) were isolated from stem bark and seeds methanolic extracts of Aspidosperma spruceanum. Compounds structures were elucidated on the basis of spectroscopic data, mainly those obtained by ¹H and 13C NMR (1D and 2D) and mass spectrometry.Dois novos alcalóides indólicos com esqueleto plumerano, spruceanuminas A (1) e B (2), e oito alcalóides indólicos conhecidos, aspidospermidina (3), desmetoxipalosina (4), aspidocarpina (5), aspidolimina (6), fendlerina (7), aspidolimidina (8), obscurinervidina (9) e obscurinervina (10), foram isolados do extrato metanólico das cascas do caule e sementes de Aspidosperma spruceanum. As estruturas dos compostos foram elucidadas com base na análise de dados espectroscópicos, principalmente os obtidos por espectros de RMN ¹H e 13C (1D e 2D) e por espectrometria de massas
Ocorrência e atividade biológica de quassinóides da última década
Quassinoids, the bitter principles of the Simaroubaceae family, are a group of structurally complex and highly oxygenated degraded triterpenes. They are divided into five groups according to their basic skeleton, C-18, C-19, C-20, C-22 and C-25. In recent years, attention has been focused on quassinoids because several of them have shown promising biological activities. This paper features a review of some characteristics of these compounds, updating known information with discoveries from the last decade and covering chemical structures, basic skeletons, occurrence in genus and species, besides detailed studies of biological activities such as antitumor, antimalarial, phytotoxic, antifeedant, insecticidal, anti-inflammatory and antiulcer
New triterpene glycoside and other chemical constituents from the leaves of Swartzia apetala
Muscicapines, a new class of guaiane-type sesquiterpene alkaloids from Croton muscicapa
Three new guaiane-type sesquiterpene alkaloids, muscicapine A (1), muscicapine B (2), and muscicapine C (3) were isolated from the roots of Croton muscicapa. The structures were established by analysis of spectroscopic data, mainly 1D and 2D NMR and MS. This is the first report of a new class of guaiane-type sesquiterpene alkaloids