The new 1-(4-(3-(aryl)acryloyl)phenyl)-1H-pyrrole-2,5-diones (5a–g) were prepared from 4′-aminchalcones (3a–g) and screened for biological activities. All compounds (3a–g and 5a–g), except 3d and 3e displayed good cytotoxic activities with IC₅₀ values in the range of 7.06–67.46 μM. IC₅₀ value of 5-fluorouracil (5-FU) was 90.36 μM. Moreover, most of compounds 5a–g showed high antibacterial activity with 8–20 mm of inhibition zone (19–25 mm of Sulbactam-Cefoperazone (SCF)). In addition, they showed good inhibitory action against acetylcholinesterase (AChE), and human carbonic anhydrase I, and II (hCA I and hCA II) isoforms. Also, these compounds demonstrated effective inhibition profiles with Ki values of 426.47–699.58 nM against hCA I, 214.92–532.21 nM against hCA II, and 70.470–229.42 nM against AChE. On the other hand, acetazolamide, clinically used drug, showed a Ki value of 977.77 ± 227.4 nM against CA I, and 904.47 ± 106.3 nM against CA II, respectively. Also, tacrine inhibited AChE showed a Ki value of 446.56 ± 58.33 nM.

Novel 4,5-dihydropyrazole derivatives (3a–i), 3-(4-((3aR,4S,7R,7aS)-1,3-dioxo-3a,4,7,7a-tetrahydro-1H-4,7-methanoisoindol-2(3H)-yl)phenyl)-5-phenyl-4,5-dihydro-1H-pyrazole-1-carbothio amide, were obtained by the addition of thiosemicarbazide (2) to the chalcones (1a–i). The addition–cyclization of 2,4′-dibromoacetophenone (4) to pyrazole derivatives (3a–i) gave the new pyrazolyl-thiazole derivatives (5a–i), (3aR,4S,7R,7aS)-2-(4-(1-(4-(4-bromophenyl)thiazol-2-yl)-5-phenyl-4,5-dihydro-1H-pyrazol-3-yl)phenyl)-3a,4,7,7a-tetrahydro-1H-4,7-methanoisoindole-1,3(2H)-dione. Antibacterial and acetylcholinesterase (AChE) enzyme and human carbonic anhydrase (hCA) I, and II isoform inhibitory activities of the compounds 3a–i and 5a–i were investigated. Some of the compounds showed promising antibacterial activity. In addition, the hCA II and I were effectively inhibited by the lately synthesized derivatives, with K_i values in the range of 18.90 ± 2.37 −58.25 ± 13.62 nM for hCA II and 5.72 ± 0.98 −37.67 ± 5.54 nM for hCA I. Also, the K_i parameters of these compounds for AChE were obtained in the range of 25.47 ± 11.11 − 255.74 ± 82.20 nM. Also, acetazolamide, clinical molecule, was used as a CA standard inhibitor that showed K_i value of 70.55 ± 12.30 nM against hCA II, and 67.17 ± 9.1 nM against hCA I, and tacrine inhibited AChE showed K_i value of 263.67 ± 91.95.