Fig. 4: Application of LC-MS2Struct to annotate stereoisomers.
Post-hoc analysis of the stereoisomer annotation using LC-MS2Struct for three (MS2, RT)-tuples from our MassBank data associated with the same 2D skeleton (InChIKey first block). In our evaluation, all three MS features were analysed multiple times in different contexts (BS02391126 in four, BS64681001 in eight and PR75447353 in two LC-MS2 experiments). a, MS features with their ground-truth annotations. Two of the spectra (starting with BS) were measured under the same LC condition (MB-subset `BS_000'), demonstrating the separation of E/Z isomers on LC columns. b, The candidate sets of the three features are identical (defined by the molecular formula C36H32O19) and contain only three structures. For 12 out of the 14 LC-MS2 experiments, LC-MS2Struct predicts the correct E/Z isomer.
