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The present work describes the synthesis, physico-chemical characteristics, antioxidative properties, and high-performance liquid chromatography (HPLC) enantioseparation of novel, potentially bioactive aryloxyaminopropanols – derivatives of naphthalen-2-ol modified in the basic part of their molecules. Reaction of naphthalene-2-ol with chloromethyloxirane leads to 2-[(naphthalen-2-yloxy)methyl]oxirane, which reacts in the next step with branched aliphatic amines (isopropylamine, tert-butylamine, and dimethylamine), aromatic amines (aniline, 3,4-dimethoxyphenylethylamine), and heterocyclic amines (pyrrolidine, imidazole, 2-methylimidazole, piperidine, morpholine, 4-methylpiperidine, or 2-methoxyphenylpiperidine). The target compounds were isolated in the form of free bases, as well as their salts with fumaric or hydrochloric acid. Their purity was established by thin-layer chromatography and their IR, UV, 1H-NMR, and 13C-NMR spectra were recorded. The antioxidant activities of prepared compounds were measured by the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) method and they were compared with the values for the corresponding salts. Enantioseparation was accomplished by means of enantioselective HPLC using amylose tris(3,5-dimethylphenyl)carbamate (Chiralpak AD), as well as Chirobiotic T (native teicoplanin) in some cases.

A homologous series of (3-alkoxymethyl-4-hydroxyphenyl)propan-1-ones was prepared by the reaction of (3-chloromethyl-4-hydroxyphenyl)propan-1-ones with the corresponding alcohols (methanol – decan-1-ol, propan-2-ol, 2-methylpropan-1-ol, 3-methylbutan-1-ol, cyclopentanol, benzylalcohol) in the presence of sodium hydrogen carbonate. The composition of the synthesised compounds was elucidated by IR, UV and 1H-NMR and 13C-NMR spectra. Selected compounds were tested against human pathogens: gram-positive bacterium Staphylococcus aureus (CNCTC Mau 29/58), gram-negative bacterium Escherichia coli (CNCTC 377/79) and yeast Candida albicans (CCM 8186). Their antimicrobial activities were expressed as minimum inhibitory concentrations. Antioxidant activity was determined using DPPH and ABTS.+ methods. It could be shown that both biological activities, antimicrobial and antioxidant, were lower in comparison with the (2RS)-bis [3-(4-acetyl-2-propoxymethyl)phenoxy-2-hydroxypropyl]isopropylammonium fumarate type of beta blockers.