Iron(II) complexes bearing N-heterocyclic carbene (NHC) ligands have emerged as promising earth-abundant dye sensitizers for applications in dye-sensitized solar cells (DSSCs). In this work, we present a computational study of a set of 42 Fe–NHC dyes derived from seven ligand frameworks, systematically functionalized with donor, acceptor, and donor–acceptor groups to tune or enhance their photophysical properties. The calculated geometries reveal that substitution modulates Fe–N bond lengths and ligand dihedral angles only slightly, preserving the structural integrity of the complexes. TD-DFT calculations show clear and predictable electronic trends: donor groups raise the HOMO, acceptor groups lower the LUMO, and the combined push–pull configuration produces the most pronounced HOMO–LUMO gap narrowing and largest redshifts in MLCT transitions. Key DSSC performance descriptors, including electron-injection and dye-regeneration free energies, light-harvesting efficiency, excited-state lifetimes, and hole-transport reorganization energies, collectively identify the double-acceptor and push–pull derivatives as the most promising candidates across multiple frameworks.

Origanum majorana L. (Lamiaceae) has been prescribed in folk medicine for therapeutic purposes such as cancer, asthma, dizziness, rheumatism and inflammatory diseases. To evaluate for the first time the decoction (DecE) and hydro–ethanolic (HEE) extracts of the aerial part of O. majorana. The phytochemical analysis (LC–MS/MS), antioxidant, anti–inflammatory and analgesic potentials were analysed. LC–MS/MS analysis identified 17 components in the extracts. The main compounds detected in the aerial parts of O. majorana include rosmarinic acid (≥ 50%), elagic acid (≥ 20%), indomethacin along with flavonoids, phenolics, benzopyrone, hydroquinones, indolyl acetic acid. Both extracts showed potent antioxidant effects in various antioxidant assay models. Through the eggs protein denaturation assay, both plant extracts showed high in vitro anti–inflammatory effect of the order of 86.91±0.00% for DecE and 85.04±0.00 % for HEE (1.4 mg·mL-1). Acute toxicity measurement revealed no mortality or behavioral changes during the testing period, confirming the two extracts not toxic with an LD50 > 2 g·kg-1. The in vivo anti–inflammatory effects were found to be statistically significant (P<0.05), reducing the edematous response by 78.40 ± 2.52 % and 77.36 ± 3.88 % in DecE and HEE, respectively. Additionally, at a dose of 400.0 mg·kg-1, both extracts exhibited significant analgesics activity (P<0.05) against acetic acid induced abdominal constriction in mice, with inhibition rates of 78.54 ± 3.30% for DecE and 66.99 ± 1.34% for HEE. The results indicate aerial part extracts of O. majorana have potent anti–inflammatory effects and may prove to have potential health benefits.