Synthesis, analysis and rearrangement of novel unnatural glucosinolates

As part of a structure activity study to examine the interaction of glucosi nolates with leaf surfaces,a number of glucosinolates were synthesised bear ing novel side chain functionalities. These included 7-carboxyheptyl, hepty l, and naphthyl side chains. For the carboxyheptyl glucosinolate, a novel i ntramolecular rearrangement reaction was observed during the final deprotec tion step, which generated an ester attached to the C-3 of glucose. Studies by H-1 NMR spectroscopy showed that the hydrophobic side chain associated with one face of the glucose ring and it was proposed that this was the dri ving force for the rearrangement. Similar hydrophobic interactions were als o observed between the heptyl and naphthyl side chains and the glucose. (C) 2001 Elsevier Science Ltd. All rights reserved.