Cobalt-based catalytic systems are being more widely used in the carbon-carbon bond formation. In comparison to some other transition metals, cobalt is easily accessible, has low toxicity and lower cost, which makes cobalt-based catalytic systems more eco-compatible and eco-friendly. Reactions take place under mild conditions. For the reaction to occur, a base and a ligand need to be added. The ligand forms a complex with the cobalt, either beforehand or in-situ. This Master's thesis is focused on the design of new glucosamine derivatives, to be used as ligands in catalytic systems, where carbon-carbon bonds were formed stereoselectively, using Grignard reagents and cobalt as a catalyst. We synthesised 8 potential ligands, of which three were used as ligands in the catalytic system.
We tested the synthesised compounds on enzymes: acetylcholinesterase, butyrylcholinesterase, monoamino oxidase A and monoamino oxidase B. Two compounds showed inhibitory activity on butyrylcholinesterase.
Lastly, we determined the ligands' chelating ability of certain transition metals. Six compounds formed complexes with cobalt (Co2+), whereas one compound formed complexes with iron (Fe2+). Compounds with chelating abilities can potentially be used as drugs – either as drugs that target metal ions in some form (chelators), or metal-based drugs, where the metal ion is crucial to the clinical application. Pharmaceutical industry is still dominated by drugs of organic origin, but numerous researches in the past decade have shown the potential of the medicinal inorganic chemistry.
Synthesised glucosamine derivates can potentially be used as:
- ligands in catalytic systems, where carbon-carbon bonds are formed;
- inhibitors for AChE, BChE, MAO-A and MAO-B;
- chelators of certain transitiona metals.
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