THE COORDINATED USE OF TANDEM MASS-SPECTROMETRY AND HIGH-RESOLUTION MASS-SPECTROMETRY FOR THE STRUCTURE IDENTIFICATION OF THE KEDARCIDIN CHROMOPHORE

Structure identification strategies for kedarcidin chromophore are des cribed using tandem mass spectrometry (MS/MS) and high-resolution MS t echniques. The strategy involves dividing a large, complex natural pro duct molecule into several smaller molecules (substructures) to simpli fy identification, Substructures are generated using the full-scan MS and MS/MS product ion scan modes, The relationship between substructur es, or mass spectral connectivity, is subsequently established using t he MS/MS precursor scan mode. Similar to the assembly of a picture puz zle, the structural borders are defined using accurate mass measuremen ts providing molecular formulas of the various substructure molecules, An iterative application of this substructure analysis scheme provide s greater substructural detail facilitating identification.