Within this work, we describe the design and synthesis of a range of novel thiochromanones based on natural products reported to possess anti-leishmanial action, and their synthetic derivatives. All compounds were elaborated via the key intermediate 2,2,6-trimethoxythiochromanone, which was modified at the benzylic position to afford various ester, amine and amide analogues, substituted by chains of varying lipophilicity. Upon testing in Leishmania, IC50 values revealed the most potent compounds to be phenylalkenyl and haloalkyl amides 11a and 11e, with IC50 values of 10.5 and 7.2 μM, respectively.