Rapid Synthesis of the Spiroketal Subunit of Neaumycin B: Stereochemical Aspects of Singly Anomeric Spiroketals and Proposal for a Stereocenter Reassignment

Org Lett. 2024 Dec 20;26(50):10774-10779. doi: 10.1021/acs.orglett.4c03751. Epub 2024 Dec 9.

Abstract

Neaumycin B is a complex polyketide that shows phenomenal cytotoxicity against U87 glioblastoma cells. The singly anomeric spiroketal core is a notable subunit in the natural product's structure. We report a rapid and convergent approach to the spiroketal group, resulting in the formation of two isomeric singly anomeric spiroketals. We describe the origin of this rarely described outcome in spirocycle formation and subsequently propose a correction to a stereocenter in the natural product.

MeSH terms

  • Biological Products / chemical synthesis
  • Biological Products / chemistry
  • Biological Products / pharmacology
  • Furans / chemical synthesis
  • Furans / chemistry
  • Furans / pharmacology
  • Humans
  • Molecular Structure
  • Polyketides / chemical synthesis
  • Polyketides / chemistry
  • Polyketides / pharmacology
  • Spiro Compounds* / chemical synthesis
  • Spiro Compounds* / chemistry
  • Spiro Compounds* / pharmacology
  • Stereoisomerism

Substances

  • Spiro Compounds
  • spiroketal
  • Polyketides
  • Furans
  • Biological Products