With a possibility of click derivatisation and fluorescent labelling of hBChE in mind, we also introduced a terminal alkyne into one of the carbamate substituentse.g., replaced Me with propargyl in 15, pent-4-yn-1-yl in 16 and undec-10-yn-1-yl in 17. This led to clickable analogues with steric demands comparable to 7, with 17 benefitting from additional van der Waals interactions. The increased steric bulk might have shifted the selectivity profile completely towards hBChE, as in 11; therefore, compounds 18, 19 and 20 with the ethyl, propargyl and isopropyl propargyl carbamate moiety were synthesised and tested. However, the selectivity factor did not exceed 350.