Elevated blood glucose and increased activities of secreted phospholipase A2 (sPLA2) are strongly linked to coronary heart disease. In this report, our goal was to develop small heterocyclic compound that inhibit sPLA2. The title compounds were also tested against α-glucosidase and α-amylase. This array of enzymes was selected due to their implication in blood glucose regulation and diabetic cardiovascular complications. Therefore, two distinct series of quinoxalinone derivatives were synthesised; 3-[N′-(substituted-benzylidene)-hydrazino]-1H-quinoxalin-2-ones 3a–f and 1-(substituted-phenyl)-5H-[1,2,4]triazolo[4,3-a]quinoxalin-4-ones 4a–f. Four compounds showed promising enzyme inhibitory effect, compounds 3f and 4b–d potently inhibited the catalytic activities of all of the studied proinflammatory sPLA2. Compound 3e inhibited α-glucosidase (IC50 = 9.99 ± 0.18 µM); which is comparable to quercetin (IC50 = 9.93 ± 0.66 µM), a known inhibitor of this enzyme. Unfortunately, all compounds showed weak activity against α-amylase (IC50 > 200 µM). Structure-based molecular modelling tools were utilised to rationalise the SAR compared to co-crystal structures with sPLA2-GX as well as α-glucosidase. This report introduces novel compounds with dual activities on biochemically unrelated enzymes mutually involved in diabetes and its complications.

[C9H14N]2[MnCl4] (I) and [C9H14N]2[CoCl4] (II) are isostructural compounds produced via gradual evaporation at room temperature. Both compounds consolidate in the tetragonal space group I4¯2d (No. 122), as shown by single-crystal X-ray diffraction observations. A slightly deformed tetrahedral geometry is formed by four chloride atoms around each cation MII (M = Mn or Co). The [C9H14N]+ groups and the isolated [MCl4]2− units are connected via C–H…Cl and N–H…Cl H-bonds to form sheets parallel to the (101¯), (011), (01¯1) and (101) planes. The morphology and the chemical composition of compounds (I) and (II)were determined here using SEM and EDX. The functional groups contained in both compounds were determined using FT-IR spectroscopy. The study of the optical characteristics showed that the two compounds exhibited semiconductor behavior. The thermal analysis (TGA-DTA) was used to determine their thermal stability.