The search for bioactive compounds against chronic diseases such as cancer and diabetesincludes curcuminoids as promising scaffolds. Here, we report the synthesis of a familyof curcuminoid analogue compounds with an extended unsaturated central chain, as follows:difluoroboron complex 1, the enolised curcuminoid 2, and its homoleptic coppercomplex 3, in moderate to good yields (68–90%). Additionally, their β-cyclodextrin (BCD)association complexes, 4 and 5, were prepared through a mechanochemical method andcharacterised by spectroscopic techniques. Complete 1H and 13C NMR assignments andNOESY correlations revealed unique solvent effects on the conformational disposition ofcompound 2, while the copper complex 3 displayed the highest extinction coefficient (1.20× 105 M−1·cm−1). Furthermore, the authentication of the polymorph of 1 and the new crystalstructures of 2 and 3, determined by single-crystal X-ray analysis, were highlighted. Althoughthe copper complex 3 initially exhibited the lowest a-glucosidase inhibitory activity(IC50 > 100 μM), it showed a significant increase (IC50 = 36.27 μM) upon association withBCD, reaching values comparable to the free ligand (IC50 = 45.63 μM). Compounds 1–5were non-toxic to healthy cells (COS-7), but compound 5 stands out as a promising candidateagainst this metabolic condition.
Tavera-Hernández et al. (Wed,) studied this question.