RESUMO
Strepyrazinone (1), a tricyclic diketopiperazine derivative with a carbon skeleton unprecedented in natural products, was isolated from the marine-derived Streptomyces sp. B223. Its structure was elucidated by spectroscopic analyses and electronic circular dichroism calculation. Compound 1 showed cytotoxic activity against HCT-116 cancer cell lines with an IC50 value of 0.34 µM.
Assuntos
Antineoplásicos , Streptomyces , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Dicetopiperazinas/farmacologia , Células HCT116 , Humanos , Estrutura MolecularRESUMO
(±)-Pratenone A (1), the first representative of natural 3-(1-naphthyl)-2-benzofuran-1(3H)-one polyketides, was isolated from a marine-derived Streptomyces pratensis strain KCB-132 together with three other new analogues (2-4). Its structure was assigned by spectroscopic analysis, and the absolute configurations of the two enantiomers separated by high-performance liquid chromatography were determined by single-crystal X-ray diffraction and electronic circular dichroism calculations. The solvent-induced racemization of 1 and a proposed biogenetic pathway to 1-4 from the co-isolated angucyclinone precursor, as well as their biological activity, are also discussed.
Assuntos
Policetídeos/química , Streptomyces/química , Antraquinonas/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Organismos Aquáticos , Benzofuranos/química , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Cristalografia por Raios X , Células HL-60 , Células Hep G2 , Humanos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Policetídeos/isolamento & purificação , Policetídeos/farmacologia , Policetídeos/toxicidade , Staphylococcus aureus/efeitos dos fármacos , Estereoisomerismo , Streptomyces/isolamento & purificaçãoRESUMO
The aim of this paper is to develop a potentiometric sensing methodology for sensitive and selective determination of neutral phenols by using a molecularly imprinted polymer as a receptor. Bisphenol A (BPA), a significant environmental contaminant, is employed as the model target. The BPA-imprinted polymer is synthesized by the semi-covalent technique and incorporated into a plasticized poly(vinyl chloride) membrane doped with the tridodecylmethylammonium salt. The present electrode shows a linear anionic potential response over the concentration range from 0.1 to 1 µM with a detection limit of 0.02 µM, and exhibits an excellent selectivity over other phenols. The proposed approach has been successfully applied to the determination of BPA released from real plastic samples. It offers promising potential in development of potentiometric sensors for measuring neutral phenols at trace levels.