SAR and lead optimization of (Z)-5-(4-hydroxy-3-methoxybenzylidene)-3-(2-morpholinoacetyl)thiazolidine-2,4-dione as a potential multi-target antidiabetic agent

In case of metabolic disorder like Diabetes mellitus (DM), a number of key enzymes are abnormally expressed and hence they might be excellent targets for antidiabetic drug design. Multi-target design strategy has recently attracted great attention to treat challenging diseases. We have previously reported a vanillin-thiazolidine-2,4-dione hybrid 3 as multitarget inhibitor of α-glucosidase, α-amylase, PTP-1B and DPP-4. The reported compound predominantly exhibited good in-vitro DPP-4 inhibition only. Current research describes the goal to optimize an early lead compound. The efforts were focused on enhancing the capability of manipulating multiple pathways at the same time for the treatment of diabetes. The central 5-benzylidinethiazolidine-2,4-dione for Lead compound (Z)-5-(4-hydroxy-3-methoxybenzylidene)-3-(2-morpholinoacetyl)thiazolidine-2,4-dione (Z-HMMTD) was left unchanged. While East and West moieties were altered by the introduction of different building blocks conceived by using a number of rounds of predictive docking studies performed on X-ray crystal structures of four target enzymes. This systematic SAR led to the syntheses of new potent multi-target antidiabetic compounds 47-49 and 55-57 with many fold increase in the in-vitro potency compared to Z-HMMTD. The potent compounds showed good in-vitro and in-vivo safety profile. Compound 56 emerged excellent as glucose-uptake promotor via hemi diaphragm of the rat. Moreover, the compounds demonstrated antidiabetic activity in STZ-induced diabetic animal model.