This invention pertains to methods, mixtures, kits and/or compositions for the determination of analytes by mass analysis using unique labeling reagents or sets of unique labeling reagents. The labeling reagents can be isomeric or isobaric and can be used to produce mixtures suitable for multiplex analysis of the labeled analytes.
Ring contraction of 2,5-diketopiperazines by TRAL-alkylation led us to the stereoselectivesynthesis of original pyrrolidine-2,4-diones, a novel series of promising molecules with moderate anti-proliferative activity on breast cancer cells.