Isolation and structural elucidation of new cyclotetrapeptides, trapoxins A and B, having detransformation activities as antitumor agents

J Antibiot (Tokyo). 1990 Dec;43(12):1524-32. doi: 10.7164/antibiotics.43.1524.


New cyclotetrapeptides, trapoxins A and B were isolated from the culture broth of Helicoma ambiens RF-1023. These compounds exhibit detransformation activities against v-sis oncogene-transformed NIH3T3 cells (sis/NIH3T3) as antitumor agents. The structures were found to be new cyclotetrapeptides, cyclo[(S)-phenylalanyl-(S)-phenylalanyl-(R)-pipecolinyl- (2S,9S)-2-amino-8-oxo-9,10-epoxydecanoyl-] for trapoxin A and cyclo[(S)-phenylalanyl-(S)-phenylalanyl-(R)-prolyl-2- amino-8-oxo-9,10-epoxydecanoyl-] for trapoxin B, by X-ray analysis, mass spectrometric, NMR and chemical studies.

MeSH terms

  • Amino Acid Sequence
  • Anti-Bacterial Agents*
  • Antibiotics, Antineoplastic / biosynthesis
  • Antibiotics, Antineoplastic / chemistry*
  • Antibiotics, Antineoplastic / isolation & purification
  • Antibiotics, Antineoplastic / pharmacology
  • Cell Line, Transformed
  • Cell Transformation, Neoplastic / drug effects*
  • Chromatography, High Pressure Liquid
  • Fermentation
  • Intercellular Signaling Peptides and Proteins
  • Magnetic Resonance Spectroscopy
  • Mass Spectrometry
  • Mitosporic Fungi / metabolism*
  • Molecular Sequence Data
  • Molecular Structure
  • Peptide Fragments / chemistry
  • Peptides*
  • Peptides, Cyclic / chemistry
  • Protein Conformation
  • Spectrophotometry, Infrared
  • Spectrophotometry, Ultraviolet
  • X-Ray Diffraction


  • Anti-Bacterial Agents
  • Antibiotics, Antineoplastic
  • Intercellular Signaling Peptides and Proteins
  • Peptide Fragments
  • Peptides
  • Peptides, Cyclic
  • trapoxin A
  • trapoxin B