In this work, we present results about the synthesis and the antioxidant properties of seven adenosine derivatives. Four of these compounds were synthesized by substituting the N6-position of adenosine with aliphatic amines, and three were obtained by modification of the ribose ring. All compounds were obtained in pure form using column chromatography, and their structures were elucidated by infrared spectroscopy (IR) and Nuclear Magnetic Resonance (NMR). All adenosine derivatives were further evaluated in vitro as free radical scavengers. Our results show that compounds 1c, 3, and 5 display a potent antioxidant effect compared with the reference compound ascorbic acid. In addition, the absorption, distribution, metabolism and excretion (ADME) calculations show favorable pharmacokinetic parameters for the set of compounds analyzed, which guarantees their suitability as potential antioxidant drugs. Furthermore, theoretical analyses using Molecular Quantum Similarity and reactivity indices were performed in order to discriminate the different reactive sites involved in oxidative processes.

We describe the semisynthesis and biological effects of adenosine derivatives, which were anticipated to function as agonists for the A₃ receptor. Molecular docking was used to select candidate compounds. Fifteen nucleoside derivatives were obtained through nucleophilic substitutions of the N⁶-position of the nucleoside precursor 6-chloropurine riboside by amines of different origin. All compounds were purified by column chromatography and further characterized by spectroscopic and spectrometric techniques, showing moderate yield. These molecules were then evaluated for their antiproliferative activity in human gastric cancer cells expressing the A₃ receptor. We found that the compounds obtained have antiproliferative activity and that new structural modifications can enhance their biological activity. The ADME (Absorption, Distribution, Metabolism and Excretion) properties of the most active compounds were also evaluated theoretically.

Quinoline is a heterocyclic scaffold of paramount importance to human race. Quinolines and their derivatives occur in numerous natural resources. Compounds containing quinoline structure are widely used as antiasthmatic, antimalarials, anti-viral, anti-inflammatory, antibacterials, antifungals, and anticancer (1). Among quinoline derivatives, tetrahydroquinolines (THQs) are an important structural subunit of natural and synthetic products and many THQs derivatives exhibit interesting biological and pharmaceutical activities (2). Many quinoline derivatives have shown anti-cholinesterase activity and can be potential agents for treatment of Alzheimer disease (3-5).In the present study we have synthesized 7 derivatives of THQs with different patterns of substituent using the Povarov reaction in presence of Lewis acid, all compounds was characterized by 1H-NMR, 13C-NMR and Mass Spectra, and evaluated as potentials inhibitors of acetylcholinesterase.