Assignment of Isomeric Hydroxyhydantoins: Linked-scan, Tandem and High-resolutions Studies

Article abstract of DOI:10.1002/oms.1210260302

The mass spectral fragmentation of hydroxyhydantoins was studied by a combination of high-resolution, linked-scan and collisionally activated decomposition (CAD) experiments.The endeavor resulted in the structural assignment of four pairs of synthetic hydroxyhydantoin isomers.A key feature in differentiating 1-methyl-3-aryl-5-hydroxy-2,4-imidazolidinediones from 1-aryl-3-methyl-5-hydroxy-2,4-imidazolidinediones is that under electron ionization (EI) conditions only the 1-methyl-3-aryl-5-hydroxy-2,4-imidazolidinediones yield the ^+* ion.The analogous ^+* ion (where Ar is the aryl group) was present in the EI spectra of both isomers and its origins are explained by the linked-scan and CAD experiments performed.