Synthesis, Antibacterial and Antitubercular Evaluation of Cardanol and Glycerol‑Based β-Amino Alcohol Derivatives

Abstract

The synthesis of novel amino alcohol derivatives based on cardanol and glycerol were achieved in good yields and characterized by 1 H and 13 C NMR (nuclear magnetic resonance) and MS (mass spectrometry). In addition, we evaluated the in vitro antimicrobial activity against Gram-positive (Staphylococcus aureus, standard and clinical strains), Gram-negative (Escherichia coli) and M. tuberculosis bacterial strains. The bioassay results indicated that four compounds showed activity against S. aureus, including the clinical resistant strain, with MIC (minimum inhibitory concentration) ranging from 3.90 to 15.60 µg mL -1 and M. tuberculosis, with MIC 90 (minimum inhibitory concentration required to inhibit the growth of 90% of organisms) ranging from 3.18 to 7.36 µg mL -1 .Keywords: CNSL, cardanol, amino alcohols, epoxide ring opening, antimicrobial activity IntroductionThe synthesis of fine chemicals from natural renewable resources has received great interest in synthetic community and is becoming a significant and challenging theme for researchers of both the academic and industrial sectors. Among the renewable materials, cardanol has attracted considerable attention due to its unique nature.1 Cardanol is a low cost, naturally occurring renewable non-isoprenoic phenolic lipid-mixture of cashew nut shell liquid (CNSL). The structural benefits of cardanol are carrying reactive phenolic group and hydrophobic alkyl/alkenyl side chain at meta-position of phenolic group. With these unique structural features, cardanol and its derivatives are renowned amphiphilic building blocks and precursors of high-value fine chemicals and supramolecular structures. Its derivatives present many biological activities such as: fungicidal, bactericidal, molluscicidal, larvicidal, anti-inflammatory, antioxidant and, towards serious disorders like cancer and obesity. [2][3][4][5][6][7][8][9] It is also described in the literature in recent years, that cardanol frameworks are involved to build phenolic resins, 10-12 bio-based polymers, 13 epoxy curing resins, 14-16 reactive diluents, 17,18 and fluorescent compounds. 19,20 Similarly, glycerol is another important renewable material used in the synthesis of higher value-added fine chemicals through green chemistry procedures in the last years. It may be applied, for instance, to generate hydrogen gas, 21 Synthesis, Antibacterial and Antitubercular Evaluation of Cardanol and Glycerol-Based β-Amino Alcohol Derivatives J. Braz. Chem. Soc. 640 Cardanol and glycerol can be starting materials to prepare β-amino alcohols which is a vital interesting class of organic intermediates due to their abundant existence in nature and they are useful in the preparation of wide range of biologically active natural and synthetic frameworks, pharmaceuticals (e.g. β-blockers), unnatural β-amino acids, pesticides and chiral auxiliaries. [29][30][31][32] Additionally, β-amino alcohols have many applications as antibiotics, anti-bacterial drugs and, steroids.33 One of the most classical approaches toward the syn...

Amino Alcohols from Eugenol as Potential Semisynthetic Insecticides: Chemical, Biological, and Computational Insights

“…The three-membered heterocyclic ring is strained and susceptible to attack by a range of nucleophiles, including nitrogen (e.g., ammonia, amines, azides), oxygen (e.g., water, alcohols, phenols, acids), and sulfur (thiol)-containing compounds, leading to bifunctional molecules of great industrial value. The β-amino alcohols are used in the synthesis of β-blockers, insecticidal agents, and oxazolines, as well as chiral ligands in asymmetric synthesis [12][13][14][15][16][17]. β-Amino alcohol functionality is found in many biologically active compounds, being an important pharmacophore [14,18], and N-substituted β-amino alcohols are important building blocks in the preparation of added-value chemicals [16,19].…”

“…The β-amino alcohols are used in the synthesis of β-blockers, insecticidal agents, and oxazolines, as well as chiral ligands in asymmetric synthesis [12][13][14][15][16][17]. β-Amino alcohol functionality is found in many biologically active compounds, being an important pharmacophore [14,18], and N-substituted β-amino alcohols are important building blocks in the preparation of added-value chemicals [16,19]. Salbutamol and propranolol are on the World Health Organization List of Essential Medicines and represent the most important examples of therapeutic agents having this structural feature [20].…”

Antimicrobial Potential of Essential Oils from Cerrado Plants against Multidrug−Resistant Foodborne Microorganisms

“…The antimicrobial activity of the essential oils was determined by the broth microdilution method, as described by Manda et al (2018) [49]. Two−fold dilutions were performed in 96−well plates prepared with Mueller-Hinton broth to reach a final concentration of 1.95 to 4000 µg•mL −1 , with a 100 µL final volume in each well.…”

Synthesis of Polycardanol Using BF3.O(C2H5)2 as Initiator: Influence of Polymerization Conditions on Reaction Products

“…The hydroxyl group of the phenol, the aromatic ring and the unsaturations of the aliphatic chain enable obtaining various types of functionalization of the cardanol molecules, making it a valuable starting material for the synthesis of various compounds, including polymers. 8,[15][16][17] The literature describes the polymerization of cardanol through different methods. Polycondensation of the material is achieved by the reaction of the phenol group with aldehydes, obtaining as a product novolac resins.…”