Abstract
In this study new sulphamethoxazole derivatives (
S1
–
S4
,
S6
–
S12
, and
S14
–
S22
) were designed and synthesized and their structures were fully characterized and validated using NMR, mass, and IR spectroscopy, as well as elemental analyses. All new derivatives (
S1
–
S22
) were assayed against human carbonic anhydrase (hCAs IX and XII) for their inhibitory activities. hCAs IX and XII were chosen due to the fact that CAIX expression is recognized as a hypoxia marker with a poor prognosis in breast cancer. When compared to Dorzolamide HCl as a standard reference, derivatives
S2
,
S3
,
S8
,
S9
, and
S15
had the most effective inhibition with low IC
50
values. The active compounds were further evaluated against hCAs I and II inhibitory activity and compounds
S8
,
S9
and
S15
showed the least inhibitory effect compared to the reference standard, acetazolamide, indicating that their effect in normal cells is the lowest. Cell viability tests for the selected compounds were carried out on MCF7 (normoxia and hypoxia) and on the normal breast cell line (MCF10a) with Staurosporine as a standard. The results showed that compound
S15
had a highly potent cytotoxic effect. Furthermore, cell cycle analysis results showed that compound
S15
triggered cell cycle arrest and apoptosis in G1/S of MCF7 cancer cells. Finally, molecular docking was performed to point out the possible explanation for the vital structural features and key-interactions exerted by our ligands with
h
CAs IX and XII that might share additional designs and highlight possible leads for a hopeful anticancer agent. Consequently, sulphamethoxazole Derivative
S15
could be the potential lead for emerging selective cytotoxic compounds directing
h
CAs IX and XII.