title: The 3-cephem chromophore.
mesh_terms: D000900:Anti-Bacterial Agents / Q000302:isolation & purification*; D002942:Circular Dichroism; D010860:Pigments, Biological; D013057:Spectrum Analysis; D013302:Streptomyces / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D010860:Pigments, Biological