RESUMO
Actinomycin Z6 (1), a new member of the actinomycin family, along with three congeners of the Z-type (Z1, Z3, Z5) actinomycins, are produced from Streptomyces sp. KIB-H714. Their structures were authenticated by comprehensive spectroscopic data interpretation. Different from all the reported Z-type actinomycins, the ß-ring of the new compound actinomycin Z6 includes an additional ring linked between the actinoyl chromophore and ß-peptidolactone. In Z3 and Z5, the L-threonine in ß-depsipeptide is replaced by the unusual 4-chlorothreonine, an amino acid rarely found in actinomycin family. All isolates were evaluated for cytotoxicity against five human tumor cell lines and for inhibitory activity against Candida albicans and Staphylococcus aureus.
Assuntos
Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Dactinomicina/análogos & derivados , Dactinomicina/farmacologia , Streptomyces/química , Anti-Infecciosos/química , Antineoplásicos/química , Candida albicans/efeitos dos fármacos , Linhagem Celular Tumoral , Dactinomicina/química , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Oxigênio/química , Espectrometria de Massas por Ionização por Electrospray , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade , Treonina/análogos & derivados , Treonina/químicaRESUMO
Constituents of the fruits of Peatasites tatewakianus were investigated. A new compound, namely bakkenolide-VI (1), was isolated. The structures was elucidated on the basis of 1D, 2D NMR, TOF-MS and ESI-MS techniques, and physicochemical properties. The neuroprotective activity of the new compound was assayed with primary cultured neurons exposed to oxygen-glucose deprivation and oxidative insults.