Bionectins A−C, Epidithiodioxopiperazines with Anti-MRSA Activity, from Bionectra byssicola F120

Abstract

Three new epidithiodioxopiperazine compounds, bionectins A (1), B (2), and C (3), along with a known compound, verticillin D (4), have been isolated from the mycelium of liquid fermentation cultures of the fungus Bionectra byssicola F120. The structures of compounds 1-3 were assigned on the basis of MS and NMR data. Compounds 1 and 2 incorporate a dioxopiperazine moiety with a disulfide bridge in their molecules, while 3 contains a dioxopiperazine ring with two methylsulfanyl groups. Compounds 1 and 2 exhibited antibacterial activity against S. aureus including methicillin-resistant S. aureus (MRSA) and quinolone-resistant S. aureus (QRSA), with MIC values of 10-30 microg/mL, while 3 showed no antibacterial activity even at 100 microg/mL.

Glioperazine B, as a New Antimicrobial Agent againstStaphylococcus aureus, and Glioperazine C: Two New Dioxopiperazines fromBionectra byssicola

“…In the course of our screening for new antibacterials from microbial metabolites, we have previously isolated bionectins A-C, 3) unique monomeric epidithiodioxopiperazines with an indole ring, and verticillin G, 4) dimeric epidithiodioxopiperazine containing a hydrodisulfide group. Further investigation of the polar metabolites of Bionectra byssicola has resulted in the isolation of two new dioxopiperazines, named glioperazines B (1) and C (2), together with the known compound, glioperazine (3) 5) (Fig.…”

“…Further investigation of the polar metabolites of Bionectra byssicola has resulted in the isolation of two new dioxopiperazines, named glioperazines B (1) and C (2), together with the known compound, glioperazine (3) 5) (Fig. 1).…”

“…2). Thus, the planar structure of 1 was assigned as a new derivative of glioperazine, 3 in which an O-methyl is attached at C-6 instead of a S-methyl. The relative configuration of 1 was determined from the NOESY (Fig.…”

Isolation and Identification of FR198248, a Hydroxylated 1,3-Dihydroisobenzofuran, fromAspergillus flavipesas an Inhibitor of Peptide Deformylase

“…20) S. aureus RN4220, MRSA CCARM3167 and QRSA CCARM 3505 were used. S. aureus was grown to the mid-log phase in Mueller-Hinton broth and diluted 1,000-fold in the same medium.…”

Ocorrência e diversidade estrutural de metabólitos fúngicos com atividade antibiótica

“…38 A partir de Bionectra byssicola foram isoladas as bionectinas A-C (88 a 90), ativas contra cepas de S. aureus resistentes à meticilina. 39 A indústria farmacêutica tem se voltado ao potencial dos metabólitos fúngicos para o desenvolvimento de novos fármacos. Singh e colaboradores, da Merck Research Laboratories, relataram recentemente o isolamento de duas substâncias interessantes, as citrafunginas A (91) e B (92), com atividade sobre fungos patogênicos em baixas doses.…”