“…Tarchonanthuslactone ( 1 ) has a privileged structure, presenting the usually bioactive α,β-unsaturated δ-lactone motif [10,11,12,13], which makes it a good target for new asymmetric synthetic approaches [14,15,16,17,18]. Interestingly, Hsu and coworkers [19] have reported that caffeic acid ( 3 ) has an antidiabetic effect and, because of the structural similarity between 1 and 3 , a number of reports have, thereafter, assigned a putative antidiabetic effect to 1 as well [14,15,16,17,18,20,21,22]. Here, we employed a mouse model of diet-induced diabetes to evaluate the effect of 1 and related compounds (Figure 1) on blood glucose levels.…”