The 15N induced isotope shift as an effective tool for the structure elucidation of 2,4 and 2,5 di-substituted thiazoles

Abstract 15 N isotope effects have been used for structural elucidation of the di-substituted thiazole 1 -DFL 23805, a novel and potent dual CXCR1/CXCR2 inhibitor, developed by Dompe within the MedChem program. The compound and its 15 N isotopologue have been synthesized according to the same proprietary procedure. The 1 H and 13 C NMR spectra have been measured. The isotope effects on chemical shifts and on coupling constants have been studied in detail. The collected data highlight a new perspective on the elucidation of disubstituted thiazole system, as only very few reference data have been published so far. All the results are consistent with the 2,4 regioisomery assignment.