Synthesis of 11C-labeled Kendine 91, a histone deacetylase inhibitor

► We labeled Kendine 91 with carbon-11. ► Despite low yields final radioactivity should allow in vivo studies. ► We synthesized the desmethylated precursor using two routes. ► Microwave assisted Paal-Knorr reaction was more efficient than (3+2) cycloaddition.