Isolation, structure elucidation and activity of an unknown impurity of amphotericin B

J Antibiot (Tokyo). 2007 Apr;60(4):272-6. doi: 10.1038/ja.2007.34.


An unknown impurity named amphotericin B (2) (AmB(2)) isolated from amphotericin B (AmB) bulk material was identified as (1S,3S,5R,6R,9R,11R,15S,16R,17R,18S,19E,21E,23E,25E,27E,29E,31E,33R,35S,36R,37S)-33-[(3-amino-3,6-dideoxy-beta-D-mannopyranosyl)oxy]-1-methyloxy-3,5,6,9,11,17,37-heptahydroxy-15,16,18-trimethyl-13-oxo-14,39-dioxabicyclo[33.3.1]nonatriaconta-19,21,23,25,27,29,31-heptaene-36-carboxylic acid according to the IUPAC. The structure was elucidated by various 1D and 2D NMR techniques, mass spectrometry and by comparison with the NMR data of AmB. Its activity against Candida albicans was evaluated by comparison with AmB.

MeSH terms

  • Amphotericin B / analysis*
  • Amphotericin B / pharmacology
  • Antifungal Agents / analysis*
  • Candida albicans / drug effects
  • Drug Contamination*
  • Magnetic Resonance Spectroscopy


  • Antifungal Agents
  • Amphotericin B