Design, synthesis, and characterization of novel thiol-derivatized ibuprofen monolayer protected gold clusters

Abstract

A series of new thiol-derivatized ibuprofen monolayer protected gold clusters have been prepared by amidation of ibuprofen with alkyl alcohol or aminophenol affording the carboxamides, N-hydroxyalkyl amide 2, and N-hydroxyphenyl amide 6, which were then tosylated with p-toluenesulfonyl chloride at hydroxyl group to give 3 and 7. Reactions of 3 and 7 with NaSH afforded the mercapto derivatives 4 and 8. Conducting Brust's reaction with a 3: 1 mole ratio of thiolate ibuprofen/ AuCl 4 - yielded polydisperse thiol-derivatized ibuprofen-MPCs 5 and 9. All compounds have been identified by NMR, MS, UV, and IR spectroscopies. Compounds 4 and 8 and the MPCs 5 and 9 have been investigated by using the method of 1H NMR spectroscopy. The broadening of the signals from 0.8 to 2.0 ppm in 1H NMR spectrum of MPCs 5 and 9 confirmed the success of the conjugation of thiol-containing derivatives with nanogold cluster. © 2013 Kuan-Han Lee et al.