Effect of hydrophobic extension of aryl enaminones and pyrazole-linked compounds combined with sulphonamide, sulfaguanidine, or carboxylic acid functionalities on carbonic anhydrase inhibitory potency and selectivity.

Design and synthesis of three novel series of aryl enaminones (3a-f and 5a-c) and pyrazole (4a-c) linked compounds with sulphonamides, sulfaguanidine, or carboxylic acid functionalities were reported as carbonic anhydrase inhibitors (CAIs) using the "tail approach" strategy in their design to achieve the most variable amino acids in the middle/outer rims of the hCAs active site. The synthesised compounds were assessed in vitro for their inhibitory activity against the following human (h) isoforms, hCA I, II, IX, and XII using stopped-flow CO2 hydrase assay. Enaminone sulphonamide derivatives (3a-c) potently inhibited the target tumour-associated isoforms hCA IX and hCA XII (KIs 26.2-63.7 nM) and hence compounds 3a and 3c were further screened for their in vitro cytotoxic activity against MCF-7 and MDA-MB-231 cancer cell lines under normoxic and hypoxic conditions. Derivative 3c showed comparable potency against both MCF-7 and MDA-MB-231 cancer cell lines under both normoxic ((IC50 = 4.918 and 12.27 µM, respectively) and hypoxic (IC50 = 1.689 and 5.898 µM, respectively) conditions compared to the reference drug doxorubicin under normoxic (IC50 = 3.386 and 4.269 µM, respectively) and hypoxic conditions (IC50 = 1.368 and 2.62 µM, respectively). Cell cycle analysis and Annexin V-FITC and propidium iodide double staining methods were performed to reinforce the assumption that 3c may act as a cytotoxic agent through the induction of apoptosis in MCF-7 cancer cells.

Arylidine extensions of 3-methyl-5-oxo-4,5-dihydro-1H-pyrazol-benzenesulfonamide derivatives: Synthesis, computational simulations and biological evaluation as tumor-associated carbonic anhydrase inhibitors.

Several pyrazole-benzene sulfonamides were reported as human carbonic anhydrase inhibitors. In this research work, a design of Arylidine-extented 5-oxo-pyrazole benzenesulfonamides (4a-i), (8a-d) and (10a-e) were reported based on tail-approach design. Beside the reported synthetic procedures and confirmation by different analytical procedures, a DFT study was employed to confirm the Z- conformer of the synthesized compounds. In vitro biological assay against four different human carbonic anhydrases took place and based on the results, SAR study was illustrated and selectivity indexes were discussed. Compounds 4g and 8a exhibited the best inhibitory activity among the target compounds with values (hCAIX: KI = 71.2 nM, hCAXII: KI = 22.5 nM), (hCAIX: KI = 34.3 nM, hCAXII: KI = 74.3 nM); respectively. Both of them were subjected to cellular assay against two different cancer cell lines with expressing nature to hCA isoforms under both normoxic and hypoxic conditions. Compound 4g showed the highest cytotoxic activity against MCF-7 cancer cell line (IC50 = 4.15 µM under hypoxic conditions and IC50 = 8.59 µM under normoxic conditions) compared to the reference drug doxorubicin under normoxic, (IC50 = 4.34 µM), and hypoxic, (IC50 = 2.23 µM), conditions. Further cellular investigations were employed to study the effect of this compound on the cell cycle of the affected cell line. Finally, molecular docking supported by molecular dynamic simulation was utilized to understand the mechanism of the inhibitory activity of two of these compounds - as representative examples- based on the designed rational.

Design and synthesis of novel 5-(4-chlorophenyl)furan derivatives with inhibitory activity on tubulin polymerization.

AIM: Discovery of novel series of colchicine binding site inhibitors (CBSIs). MATERIALS & METHODS: Isoxazoline 3a-d, pyrazoline 4a-b, 7a-f and 8a-f, cyclohexenone 9a-b and 10a-b or pyridine derivatives 11a-b were synthesized and evaluated for their inhibition of tubulin polymerization and cytotoxicity. Most of the compounds displayed potent to moderate antitumor activity against leukemia SR cell line.7c, 7e and 11a were more potent than colchicine with IC50 of 0.09, 0.05 and 0.06 µM, and percentage inhibition in tubulin polymerization of 95.2, 96.0 and 96.3%, respectively. Compounds 7c and 11a showed cell-cycle arrest at G2/M phase and induced apoptosis and were able to bind the colchicine binding site of tubulin with comparable affinity to colchicine. Docking study showed that these compounds may interact with tubulin exploiting a binding cavity not commonly reported in the binding of CBSI. CONCLUSION: Compounds 7c and 11a may be considered as promising CBSI based on their excellent activity and favorable drug likeness profile.