MASP - A PROGRAM PREDICTING MASS-SPECTRA OF COMBINATORIAL LIBRARIES

MASP, a program predicting fragmentation-free mass spectra of librarie s prepared by combinatorial synthesis, is presented. MASP combines use r-defined building blocks with a nonvariable core molecule and calcula tes isotopically resolved mass spectra. Peak overlap and the abundance of major and minor isotope peaks can be examined interactively and re ad from a color display of the spectrum. Further, MASP exhaustively sc reens a Meta-Library Space to identify libraries with minimum peak ove rlap and maximum diversity. Diversity can be defined by the user, e.g. , as size, hydrophobicity, or hydrogen bonding capability. The usefuln ess of such a screen for the design of libraries is demonstrated for m eso-substituted tetraphenylporphyrins and peptides with a meta-library space of up to 3080 libraries and 625 compounds per library. The prog ram operates on a PC platform under MS Windows 95. It may be useful fo r drug discovery and optimization studies that employ methods of combi natorial synthesis and mass spectrometry-guided in vitro selection.