An MS/MS library on an ion-trap instrument for efficient dereplication of natural products. Different fragmentation patterns for [M + H]+ and [M + Na]+ ions.

The structural novelty of lead compounds is very important in the agrochemical and pharmaceutical industries, and as such, natural products can be an important source. Taking into account that the isolation of lead compounds is very time-consuming, the efficient and safe identification of compounds in microorganism and plant extracts isolated previously is essential. A suitable procedure for this task based on an HPLC system interfaced with an electrospray (ESI) source and a Thermo Finnigan LCQ deca XP plus ion-trap mass spectrometer was developed, and an extensive MS/MS spectral library of characterized natural products was built up.