Antibacterial sorbicillin and diketopiperazines from the endogenous fungus Penicillium sp. GD6 associated Chinese mangrove Bruguiera gymnorrhiza

Chin J Nat Med. 2018 May;16(5):358-365. doi: 10.1016/S1875-5364(18)30068-2.

Abstract

One new sorbicillin derivative, 2-deoxy-sohirnone C (1), one new diketopiperazine alkaloid, 5S-hydroxynorvaline-S-Ile (2), and two naturally occurring diketopiperazines, 3S-hydroxylcyclo(S-Pro-S-Phe) (3) and cyclo(S-Phe-S-Gln) (4), together with three known compounds were isolated from the Chinese mangrove endophytic fungus Penicillium sp. GD6. Their structures were determined on the basis of extensive spectroscopic analyses and by comparison with literature data. The absolute configuration of 3-hydroxyl moiety in 3 was determined by Mosher's method, while the absolute stereochemistry of 2 and 4 was established by comparison with the CD spectra of natural and synthesized diketopiperazines. Compound 1 showed moderate antibacterial activity against Methicillin-resistant Staphylococcus aureus with a MIC value of 80 μg·mL-1.

Keywords: Diketopiperazine alkaloids; Mangrove; Penicillium sp.; Sorbicillin derivative.

MeSH terms

  • Alkaloids / chemistry
  • Alkaloids / isolation & purification
  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / isolation & purification
  • Anti-Bacterial Agents / pharmacology*
  • China
  • Circular Dichroism
  • Diketopiperazines / chemistry*
  • Diketopiperazines / isolation & purification
  • Methicillin-Resistant Staphylococcus aureus / drug effects*
  • Microbial Sensitivity Tests
  • Molecular Structure
  • Nuclear Magnetic Resonance, Biomolecular
  • Penicillium / chemistry*
  • Resorcinols / chemistry*
  • Resorcinols / isolation & purification
  • Resorcinols / pharmacology*
  • Rhizophoraceae / microbiology*
  • Wetlands

Substances

  • Alkaloids
  • Anti-Bacterial Agents
  • Diketopiperazines
  • Resorcinols
  • sorbicillin