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Marine Algal Secondary Metabolites Are a Potential Pharmaceutical Resource for Human Society Developments
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Somasundaram Ambiga, Raja Suja Pandian, Lazarus Vijune Lawrence, Arjun Pandian, Ramu Arun Kumar, Bakrudeen Ali Ahmed Abdul
Lipases catalyze the conversion of oils and fats into free fatty acids, diacylglycerols, monoglycerols, and glycerol. It is also useful in various processes, including esterification, transesterification, and aminolysis. Lipases have recently received a lot of attention, as indicated by the growing amount of knowledge about them in current research. Several microbial lipases are also commercially accessible, with the majority of them being used in detergents, food flavoring, paper manufacturing industry, cosmetic industry, and organic synthesis, as well as various industrial uses.
Medicinal Plants of Mongolia
Published in Raymond Cooper, Jeffrey John Deakin, Natural Products of Silk Road Plants, 2020
Narantuya Samdan, Odonchimeg Batsukh
More than 660 PAs and PA N-oxides have been identified in over 6,000 plants, and about half of these compounds exhibit hepato-toxicity (Radominska-Pandya, 2010). While certain PAs may themselves show little toxicity, the compounds can undergo change in the liver of humans and animals to become highly toxic, alkylating pyrroles, which have (i) a double-bond in position 1,2 of the necine, (ii) a non-substituted alpha – position next to the nitrogen atom, and (iii) di-esterification of the OH-groups of the necine (monoesters are less toxic) (Hartmann and Witte, 1995; Rizk, 1991).
Emollient Esters and Oils
Published in Randy Schueller, Perry Romanowski, Conditioning Agents for Hair and Skin, 2020
John Carson, Kevin F. Gallagher
The properties may be better understood if we examine the structure of a "typical" synthetic ester and its synthesis route. As an example we'll look at isopropyl myristate (IPM), a well-known ester used in personal care products. IPM is manufactured by combining isopropyl alcohol (IPA) and myristic acid. Typically this is done in the presence of an acid catalyst under conditions where the water produced by the esterification can be removed to allow the reaction to continue to completion. Figure 6 provides an illustration of this reaction. In this case, isopropyl alcohol quantities in excess of the stoichiometric amount needed for the reaction are frequently used since some IPA is removed with the water from the reaction.
Antimicrobial activity of flavonoids glycosides and pyrrolizidine alkaloids from propolis of Scaptotrigona aff. postica
Published in Toxin Reviews, 2023
T. M. Cantero, P. I. Silva Junior, G. Negri, R. M. Nascimento, R. Z. Mendonça
Pyrrolizidine alkaloids (1–3, 5, 7–9, 13, 14, 16, 18–26) and quinolone alkaloids (4 and 6), were detected in fraction 40MEP and 40AEP. The pyrrolizidine alkaloids 16, 18–22 are glycosilated. 3′-O-Glucosyllycopsamine and 3′-O-glucosylintermedine and the corresponding N-oxides were identified in honey samples containing high contents of lycopsamine-type PAs/PANOs (Hungerford et al. 2019). Pyrrolizidine alkaloids are widely known to possess hepatotoxicity. Contamination of grains and tea with pyrrolizidine alkaloids has been the cause of liver disease in several parts of the world. Acute hepatotoxicity by pyrrolizidine alkaloids is not common, but continued ingestion of these food contaminants has resulted in chronic liver diseases. Toxicity of the PAs involves unsaturation of the 1,2 position and esterification of at least one of the hydroxyl groups with an acid and increases with the degree of branching and formation of long cyclic diesters. However, PAs are pro-toxins as they require metabolic activation to exert toxic effects (Celano et al. 2019, Hungerford et al. 2019, Sixto et al. 2019, Wang et al. 2019, De Jesus Inacio et al. 2020). No quantification analysis of PA has been carried out in the present work and is not possible to evaluate possible risks to human health derived from toxic doses of pyrrolizidine alkaloids in the propolis analyzed.
Smart design of patient-centric long-acting products: from preclinical to marketed pipeline trends and opportunities
Published in Expert Opinion on Drug Delivery, 2022
Céline Bassand, Alessia Villois, Lucas Gianola, Grit Laue, Farshad Ramazani, Bernd Riebesehl, Manuel Sanchez-Felix, Kurt Sedo, Thomas Ullrich, Marieta Duvnjak Romic
Oil-based LAI is another common prodrug formulation (Table 3), where the drug release is tailored by both slow drug release from fatty tissues and slow cleavage of the linker via hydrolysis of ester bond [84]. Esterification of a drug with a long-chain fatty acid increases its solubility in the oil formulation and its partitioning in the fatty tissues, which further extends the release kinetics [3]. As reflected in Table 3, recent development does not prefer oil-based systems. Nonetheless, the majority of small-molecule LAIs in the current drug development depend on adequate depot formulation strategies rather than prodrug concepts (Figure 2 ‘Technology’) [85]. In the case of local delivery, the administration of prodrugs to an immunologically challenged environment (e.g. inflamed articular joints or injured soft tissues) is particularly difficult. The cleavage rate of prodrugs may be sensitive to small, but significant, changes in local compartments (pH, fluid volume, temperature, or the biofluid composition at the site of injection). This leads to a more complex preclinical assessment of drug disposition and toxicity and eventually to inter-patient variability and therefore hardly controllable depot performance in clinical trials. In addition, recent technological advances in formulation science may make depot formulation more attractive for pharmaceutical R&D.
Discovery of 3,6-disubstituted pyridazines as a novel class of anticancer agents targeting cyclin-dependent kinase 2: synthesis, biological evaluation and in silico insights
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2020
Ahmed Sabt, Wagdy M. Eldehna, Tarfah Al-Warhi, Ohoud J. Alotaibi, Mahmoud M. Elaasser, Howayda Suliman, Hatem A. Abdel-Aziz
The target 5-(trifluoromethyl)pyridazine-3-carboxamide derivatives (11a–r) were prepared through several synthetic steps (Schemes 1–3) starting from the commercially available ethyl 3,3,3-trifluoropyruvate. With respect to Scheme 1, ethyl trifluoropyruvate (1) reacted with acetone in the existence of L-proline and DMF following a reported method31 to yield ethyl 2-hydroxy-4-oxo-2-(trifluoromethyl)pentanoate (2), the later compound was converted into 6-methyl-4-(trifluoromethyl)pyridazin-3(2H)-one (3) upon reaction with hydrazine hydrate in the existence of acetic acid32. Compound (3) was then subjected to oxidation process using potassium chromate and sulphuric acid at room temperature to give 6-oxo-5-(trifluoromethyl)-1,6-dihydropyridazine-3-carboxylic acid (4). Fischer esterification was then carried out for compound (4) through reflux with ethanol in the presence of sulphuric acid (catalytic amount) in order to afford the corresponding ester derivative (5), Scheme 1.