Methazolamide

Reactive oxygen species (ROS) are generated as byproducts of oxygen metabolism and play multiple roles in biol. systems.In addition, these species can be generated in the eye as a result of the photosensitizing action of pigments that are naturally present in this organ, such as riboflavin.An imbalance between the production of ROS and the response of the antioxidant defense system results in oxidative stress.In humans, the oxidative stress can lead to the initiation or development of many ocular diseases and injuries (glaucoma, cataracts, macular degeneration).In this highly oxidative cellular environment, topically administered drugs for the treatment of various pathologies may be susceptible to be attacked by ROS and consequently degraded, losing their clin. efficacy or generating toxic products.In this contribution, the kinetics of ROS-mediated degradation of the antiglaucoma drugs, acetazolamide and methazolamide, was investigated.In order to analyze the effects that these drugs and their derivatives produce on the viability of normal human cells, this parameter was evaluated in the MRC-5 line.Results showed that acetazolamide and methazolamide interact with the electronic triplet state of riboflavin and with different photo-generated ROS from this state.Both drugs were chem. degraded by singlet oxygen, although methazolamide was more reactive than acetazolamide.The experiments demonstrated that neither the drugs nor their ROS-mediated oxidation products exhibited cytotoxicity in the MRC-5 cell line.On the other hand, under direct UV irradiation, AZ and MZ generated O₂(¹Δ_g) with considerable efficiency compared to other ophthalmic drugs and would be considered good sensitizers.

This study presents the green synthesis, pharmacological evaluation, and in silico analysis of aromatic sulfonamide derivatives for their inhibitory effects on human carbonic anhydrase (hCA) isoforms I, II, IX, and XII and their antioxidant properties. The compounds were synthesized via a one‐step green synthetic method using acetic acid as the solvent, providing a straightforward and environmentally considerate approach. The synthesized compounds were confirmed to have 95% to 100% purities via HPLC purity analysis. The inhibition constants (Ki) against hCA I varied between 240 nM and 2185 nM, while inhibition of hCA II was observed with Ki values ranging from 19 to 83 nM. For hCA IX and hCA XII, the Ki values were found from 25 to 882 nM and 8.8 to 175 nM, respectively. These sulfonamides exhibited significant inhibition compared to standard carbonic anhydrase inhibitors such as acetazolamide, ethoxzolamide, zonisamide, methazolamide, dorzolamide, and SLC‐0111. The antioxidant activity, assessed using the DPPH assay, was moderate to low, with compound 6 demonstrating a noteworthy IC50 of 62.8 µg/mL, comparable to the IC50 of ascorbic acid (64.7 µg/mL). Quantum chemical analyses, including FMO, Mulliken population analysis, and electrostatic potential, total electron density, and molecular electrostatic potential analysis, demonstrated significant electrostatic interactions and optimal charge distribution. DFT calculations revealed stable chemical behavior with favorable values for hardness, softness, electronegativity, and electrophilicity. Molecular docking studies provided insights into the binding interactions, while MD simulations (10 ns) revealed the stability of the protein‐ligand complexes. ADMET predictions indicated favorable physicochemical properties and compliance with Lipinski's rule. These results highlight the potential of these aromatic sulfonamide derivatives as potent inhibitors of human carbonic anhydrase isoforms, with promising antioxidant activity, suggesting their potential therapeutic applications in conditions such as retinal and cerebral edema, glaucoma, epilepsy, high‐altitude sickness, and cancer.