Several oxidative processes are related to a wide range of human chronic and degenerative diseases, like Alzheimer’s disease, which also has been related to cholinergic processes. Therefore, search for new or improved antioxidant molecules with acetylcholinesterase activity is essential to offer alternative chemotherapeutic agents to support current drug therapies. A series of chalcone (2a–2k) and flavone (3a–3k) analogs were synthesized, characterized, and evaluated as acetylcholinesterase (AChE) inhibitors, and antioxidant agents using 1,1-diphenyl-2-picrylhydrazyl (DPPH•), 2-2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS•), and β-carotene/linoleic acid bleaching assay. Compounds more active were 3j and 2k in DPPH with EC50 of 1 × 10−8 and 5.4 × 10−3 μg/mL, respectively; 2g and 3i in ABTS (1.14 × 10−2 and 1.9 × 10−3 μg/mL); 2e, 2f, 3f, 2j, and 3j exceeded the α-tocopherol control in the β-carotene assay (98–99% of antioxidant activity). At acetylcholinesterase inhibition assay, flavones were more active than chalcones; the best results were compounds 2d and 3d (IC50 21.5 and 26.8 µg/mL, respectively), suggesting that the presence of the nitro group enhances the inhibitory activity. The docking of these two structures were made to understand their interactions with the AChE receptor. Although further in vivo testing must be performed, our results represent an important step towards the identification of improved antioxidants and acetylcholinesterase inhibitors.
The employment of privileged scaffolds in medicinal chemistry supplies scientists with a solid start in the search for new and improved therapeutic molecules. One of these scaffolds is the imidazole ring, from which several derivatives have shown a wide array of biological activities. A series of 2,4,5-triphenyl imidazole derivatives were synthesized, characterized, and evaluated in vitro as antioxidant molecules using 1,1-diphenyl-2-picrylhydrazyl (DPPH.) and 2-2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS.+) assays, acetylcholinesterase (AChE) and xanthine oxidase (XO) inhibitors as well as antiproliferative agents. Additional in silico studies such as docking and determination of their absorption, distribution, metabolism, and excretion (ADME) properties were calculated. Compounds 3 and 10 were the most active antioxidants in both the DPPH and ABTS assays (EC50 of 0.141 and 0.174 mg/mL, and 0.168 and 0.162 mg/mL, respectively). In the enzymatic inhibition, compound 1 showed the best activity, inhibiting 25.8% of AChE at a concentration of 150 μg/mL, and compound 3 was the most active XO inhibitor with an IC50 of 85.8 μg/mL. Overall, against the six different evaluated cancerous cell lines, molecules 2, 10, and 11 were the most antiproliferative compounds. In silico predictions through docking point out 11, and ADME analysis to 11 and 12, as good candidates for being lead compounds for further derivations.
9 February 2021 in Mini-Reviews in Medicinal Chemistry
The available scientific literature regarding tanshinones is very abundant, and after its review, it is noticeable that most of the articles focus on the properties of tanshinone I, cryptotanshinone, tanshinone IIA, sodium tanshinone IIA sulfonate and the dried root extract of Salvia miltiorrhiza (Tan- Shen). However, although these products have demonstrated important biological properties in both in vitro and in vivo models, their poor solubility and bioavailability have limited their clinical applications. For these reasons, many studies have focused on the search for new pharmaceutical formulations for tanshinones, as well as the synthesis of new derivatives that improve their biological properties. To provide new insights into the critical path ahead, we systemically reviewed the most recent advances (reported since 2015) on tanshinones in scientific databases (PubMed, Web of Science, Medline, Scopus, and Clinical Trials). With a broader perspective, we offer an update on the last five years of new research on these quinones, focusing on their synthesis, biological activity on noncommunicable diseases and drug delivery systems, to support future research on its clinical applications.
In the current study, chemical composition of cultivated Salvia canariensis L was determined. Carnosol was the main product isolated. We prepared more lipophilic derivatives from carnosol, and both isolated and semisynthetic abietane diterpenes were evaluated in vitro as inhibitors of squalene synthase. Among the compounds tested, carnosol was the most potent inhibitor (IC50 = 17.6 μM). These results highlight the great potential of this species for the production of new ingredients in nutritional supplements for the treatment of hyperlipidemia.
We synthesized seven (Z)-benzylidene-2-(E)-styryloxazol-5(4H)-ones derivatives of cinnamic acid and evaluated the ability of these compounds to inhibit human acetylcholinesterase (hAChE). The most potent compound was evaluated for cognitive improvement in short-term memory. The seven compounds reversibly inhibited the hAChE between 51 and 75% at 300 μM, showed an affinity (Ki) from 2 to 198 μM, and an IC50 from 9 to 246 μM. Molecular docking studies revealed that all binding moieties are involved in the non-covalent interactions with hAChE for all compounds. In addition, in silico pharmacokinetic analysis was carried out to predict the compounds’ blood–brain barrier (BBB) permeability. The most potent inhibitor of hAChE significantly improved cognitive impairment in a modified Y-maze test (5 μmol/kg) and an Object Recognition Test (10 μmol/kg). Our results can help the rational design of hAChE inhibitors to work as potential candidates for treating cognitive disorders.
Sonochemistry is recently used to improve the zeolitization process and post-synthetic treatments of potential zeolite-based catalysts. This work explores the use of ultrasound to synthesize a faujasite zeolite with a Y-type structure and the reported interconversions associated with FAU. Reviewing the effects of sono-assisted treatments of Y zeolite for the formation of mesopores and modification with alkaline metals, alkaline earth metals, and metals. Based on this specified literature review, preliminary work was conducted, employing ultrasound irradiation to synthesize a selective catalyst for oxidizing benzene to phenol (OBP). The sono-assisted synthesized zeolite Y was sonochemically ion-exchanged and modified in an ammonia buffer solution with dissolved Fe. The catalyst activity for the OBP was measured by UV-Vis spectroscopy and GC/MS, with no significant difference between the techniques, and an enhanced selectivity. This preliminary study highlights the importance of the sonochemical method for potentially designing a catalyst for the benzene-to-phenol reaction.