RESUMO
Ten new withanolides (1-10) and three artificial withanolides (11-13) were isolated from the aerial parts of Tubocapsicum anomalum, together with five known analogues (14-18). Their structures were determined on the basis of extensive spectroscopic and chemical methods. They include seven acnistin-type (1-4, 11, 14 and 15), three withajardin-type (5-7), and eight normal-type (8-10, 12, 13 and 16-18) withanolides. Of normal-type withanolides, a chemical conversion from the 16α,17α-epoxywithanolide (16) to Δ13,14-16α-hydroxywithanolide (18) was achieved by Wagner-Meerwein rearrangement. All isolates were evaluated for their cytotoxicity against four human tumor cell lines (HCT-116, HepG2, MCF-7 and A375). Among them, compounds 1-3, 6-8, 14, 16-18 showed cytotoxic activity with IC50 values of 0.24-8.71⯵M.
Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Solanaceae/química , Vitanolídeos/química , Vitanolídeos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citotoxinas/química , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Humanos , Modelos Moleculares , Neoplasias/tratamento farmacológico , Componentes Aéreos da Planta/química , Vitanolídeos/isolamento & purificaçãoRESUMO
Two new phthalide dimers (1 and 2) were obtained from the rhizomes of Ligusticum sinense Oliv., along with three known dimeric phthalides (3-5). Their structures were determined with the aid of the spectroscopic data, and their absolute configurations were elucidated based on the comparison of calculated and experimental electronic circular dichroism (ECD) spectra. All the compounds were evaluated in vitro for their inhibitory activities against NO production in LPS-treated RAW264.7 macrophages. Among them, compounds 1 and 3 showed potent NO prohibitive activity with IC50 values at 4.86 ± 0.29 µM and 4.87 ± 0.32 µM, respectively.
Assuntos
Benzofuranos/farmacologia , Ligusticum/química , Rizoma/química , Animais , Benzofuranos/isolamento & purificação , China , Camundongos , Estrutura Molecular , Óxido Nítrico , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Plantas Medicinais/química , Células RAW 264.7RESUMO
Five new prenylated acetophenones, melicoptelins A-E (1-5), along with one known congener (6) were isolated from the roots of Melicope ptelefolia. Among them, compounds 2a/2b, 3a/3b, and 4a/4b were obtained as inseparable interconverting mixtures of keto and enol tautomers. Their structures were elucidated on the basis of extensive spectroscopic methods, including 1D, 2D NMR and HRESIMS. Compouds 2a/2b, 4a/4b and 5 exhibit protein tyrosine phosphatase 1B (PTP1B) inhibitory activity with IC50 values of 34.4, 55.2 and 66.6⯵M, respectively.