Abstract

Chalcones are naturally occurring, biologically active molecules generating interest from a wide range of researchapplications including synthetic methodology development, biological activity investigation and studying fragmentation patterns. Inthis article, a series of chalcones has been synthesized and their fragmentation behavior was studied using modern ambient ionizationtechnique Direct Analysis in Real Time (DART). DART ion source connected with an ion trap mass spectrometer wasused for the fragmentation of various substituted chalcones. The chalcones were introduced to the DART source using a glasscapillary without sample preparation step. All the chalcones showed prominent molecular ion peaks [M]•+ corresponding to thestructures. Multistage mass spectral data MSn (MS2 and MS3) were collected for all the chalcones studied. The chalcones withsubstitutions at 3, 4 or 5 positions gave product ion peaks with the loss of a phenyl radical (Ph•) by radical initiated α-cleavage,while substitution at 2 position of chalcone in the A-ring gave a product ion peak with the loss of substituted styryl radical(PhCH = CH•). In case of the chalcones with the substituent at 4 positions in A and B rings gave both types of fragmentation patterns. In conclusion, chalcones can be easily characterized using modern DART interface in very short time and efficientlywithout any cumbersome sample pretreatment.