Cancer remains one of the leading causes of death worldwide. The interest in organometallic complexes as anticancer drug candidates continues to be pivotal for many researchers. Initially underestimated for their therapeutic potentials, rhenium complexes are now slowly gaining momentum. While tricarbonyl complexes of rhenium are widely investigated, dicarbonyl derivatives of the cis-[Re(CO)₂]⁺ core remain largely unexplored. In this study, we tested in vitro a variety of rhenium dicarbonyl complexes for their activity towards three cancer cell lines (A549, MCF-7 and HCT116) and one healthy cell line (HEK293). The most lipophilic compounds showed, like the tricarbonyl species, good activity against specific cancer lines (IC₅₀ = 1.5–2.5 µM); however, the same were also toxic towards healthy cells. In order to understand these differences, we performed a reactivity study of cis-[Re(CO)₂(NN)]⁺ species (where NN = diimine) with biologically relevant functional groups (-COOH, -NH₂, -SH and aromatic nitrogen-based ligands) and compared the chemistry to what is known for the fac-[Re(CO)₃]⁺ core. Overall, we found that the rhenium dicarbonyl complexes only show good reactivity with aromatic nitrogen-based ligands. The reaction of cis-[Re(CO)₂(NN)]⁺ species with common bio-functional groups leads, rather, to the formation of bis-diimine dicarbonyl complexes (cis-[Re(CO)₂(NN)₂]⁺) as the major by-product.

Antimicrobial resistance (AMR) poses a critical global health threat by rendering existing antibiotics ineffective against infections, leading to increased mortality, prolonged illnesses, and higher healthcare costs. Developing new antibiotics is essential to combat resistant pathogens, safeguard modern medical procedures, and prevent a return to a pre-antibiotic era where common infections become untreatable. We report a series of chiral tricarbonyl rhenium(I) complexes incorporating enantiopure pinene-substituted bipyridine ligands (L#) of the general formula fac-[Re(CO)₃L#X] and fac-[Re(CO)₃L#Py]⁺ (where X = Cl or Br and Py = pyridine). These complexes were isolated as mixtures of two diastereomers, characterized by standard techniques, and evaluated for cytotoxic activity against methicillin-resistant and methicillin-sensitive Staphylococcus aureus (MRSA and MSSA). The results revealed notable antibacterial efficacy (MIC = 1.6 μM), reflected in high therapeutic indices (Ti > 10). In contrast, analogous complexes bearing non-chiral 2,2′-bipyridine ligands exhibited no activity, underscoring the critical role of chirality in modulating biological interactions at the molecular level. These findings highlight the potential of chiral Re(I) complexes as promising scaffolds for the development of more potent and selective antibacterial agents.

The use of green solvents is a key element in making chemical processes more sustainable. In this work, three biobased solvents, diformyl xylose (DFX), dipropyl xylose (DPX), and n ‐butyl tetrahydrofurfuryl ether (Solvinol), were tested as cosolvents in the Suzuki–Miyaura reaction using micellar catalysis in water (TPGS‐750‐M system). 2% DPX gave > 99% conversion and 86% yield, while 2% DFX reached 86% conversion and 82% yield. Solvinol required 15% loading to give similar results. DFX was easily removed in the aqueous phase upon work‐up, while DPX and Solvinol were more difficult to remove due to their poor water solubility and high boiling points. These results demonstrate the potential of biomass‐derived solvents as green alternatives to classical organic solvents. The overall environmental efficiency of the various processes was assessed via our internal methodology. Their efficiency at low loadings supports their use in more sustainable and environmentally friendly processes.