RESUMO
Three new cyclic heptapeptides, talaromides A-C (1-3), were isolated from cultures produced by the fungus Talaromyces siglerae (Ascomycota), isolated from an unidentified sponge. The structures, featuring an unusual proline-anthranilic moiety, were elucidated by analysis of spectroscopic data and chemical transformations, including the advanced Marfey's method and GITC derivatization. Talaromides A and B inhibited migration activity against PANC-1 human pancreatic cancer cells without significant cytotoxicity.
Assuntos
Peptídeos Cíclicos , Poríferos , Talaromyces , Talaromyces/química , Animais , Poríferos/microbiologia , Humanos , Estrutura Molecular , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/química , Peptídeos Cíclicos/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Biologia Marinha , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificaçãoRESUMO
Three unique linear oligomeric depsipeptides, designated as cavomycins A-C (1-3), were identified from Streptomyces cavourensis, a gut bacterium associated with the annelid Paraleonnates uschakovi. The structures of these depsipeptides were determined through a combination of spectroscopic methods and chemical derivatization techniques, including methanolysis, the modified Mosher's method, advanced Marfey's methods, and phenylglycine methyl ester derivatization. The unique dipeptidyl residue arrangements in compounds 1-3 indicate that they are not degradation products of valinomycin. Compound 2 and its methylation derivative 2a exhibited antiproliferative activity against PANC-1 pancreatic cancer cells with IC50 values of 1.2 and 1.7 µM, respectively.
Assuntos
Depsipeptídeos , Streptomyces , Streptomyces/química , Depsipeptídeos/farmacologia , Depsipeptídeos/química , Depsipeptídeos/isolamento & purificação , Humanos , Estrutura Molecular , Animais , Ensaios de Seleção de Medicamentos Antitumorais , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificaçãoRESUMO
A chemical investigation of the endophytic Streptomyces sp. HBQ95, associated with the medicinal plant Cinnamomum cassia Presl, enabled the discovery of four new piperazic acid-bearing cyclodepsipeptides, lydiamycins E-H (1-4), and one known compound (lydiamycin A). Their chemical structures, including absolute configurations, were defined by a combination of spectroscopic analyses and multiple chemical manipulations. Lydiamycins F-H (2-4) and A (5) exhibited antimetastatic activity against PANC-1 human pancreatic cancer cells without significant cytotoxicity.