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Alkaloids as Important Scaffolds in Therapeutic Drugs for the Treatments of Cancer, Tuberculosis, and Smoking Cessation

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Abstract

Alkaloid molecules can act, depending on a type of amine functionality present in alkalods, as either hydrogen-acceptor or hydrogen-donor for hydrogen bonding that is critically important for the interaction (binding) between targets (enzymes, proteins and receptors) and drugs (ligands). Because of this unique property, alkaloid scaffolds are therefore present in several drugs and lead compounds. This review highlights alkaloid scaffolds in drugs, particularly those recently approved in 2012; it also covers the scaffolds in leads and drug candidates which are in clinical trials and preclinical pipeline. The review focuses on three therapeutic areas including treatments of cancer, tuberculosis, and tobacco cessation. Alkaloid scaffolds in drugs and leads are inspired by those of naturally occurring alkaloids, and these scaffolds include pyridine, piperidine, quinoline, quinolinone, quinazoline, isoquinoline, indole, indolinone, isoindole, isoxazole, imidazole, indazole, thiazole, pyrazole, oxazolidinone, oxadiazole, and benzazepine. In addition to medicinal chemistry aspects, natural products possessing an individual alkaloid scaffold, as well as the mechanism of action of drugs and leads, are also discussed in this review.
... Alkaloids, synthesized primarily for plant defense against pathogens and predators, exhibit various pharmacological activities, including antibacterial, anticancer, and antimalarial effects (Kittakoop et al., 2014). In this study, total alkaloid content in V. indica seeds showed minimal variation across accessions, ranging from 18.30 ± 0.05-19.48 ...
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Vigna indica is Crop Wild Relative (CWR) of widely cultivated Vigna aconitifolia. In this study, we evaluated the nutritional potential of V. indica seeds collected from five different geographical locations. Proximate composition and mineral content were estimated using AOAC methods, while, phytochemical constituents, antioxidant activity, GC-MS and FTIR profiling was done using methanolic extract of seed powder. The seeds exhibited low moisture content (14–15 %), ash content (4.95–5.00 %), and significant levels of carbohydrates (23.73–35.74 g/100 g) and proteins (35.68–40.99 g/100 g), with protein content particularly high. Seed extracts showed a substantial total phenolic content (82.69 ± 1.14 mg/GAE/100 g), total flavonoid content (58.79 ± 0.24 mg/RE/100 g), total tannin content (28.82 ± 0.72 mg/TAE/100 g), and total alkaloid content (19.48 ± 0.03 mg/CoE/100 g). Although alkaloid content was lower compared other phytochemicals, the high phenolic and flavonoid levels confirmed strong antioxidant capacity, as indicated by DPPH (79.17 ± 1.12–81.26 ± 0.15 mg RSA/100 g), FRAP (62.12 ± 0.27–66.12 ± 0.09 mg Fe/100 g), and phosphomolybdenum (2.09 ± 0.48–2.38 ± 0.82 mg AAE/100 g) assays. FTIR profiling revealed the presence of various functional groups of chemical compounds, while GC-MS analysis identified bioactive compounds in the seed extract. Overall, the findings provide valuable in sights into the nutritional and phytochemical composition of Vigna indica seeds, highlighting their potential for use in functional foods and in crop improvement programs aimed at enhancing the nutritional content and health-promoting properties of V. aconitifolia.
... Chiral diamines, especially those bearing two different amine moieties, are among the most fundamental structures found in a wide array of natural products, agrochemicals and pharmaceuticals (Fig. 1a refs. [18][19][20]. One of the most straightforward methods for generating unsymmetrical diamines is through the enantioselective assembly of two different aliphatic amine congeners to olefins in a one-step manner 21 . ...
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... Alkaloids have served as the basis for the development of numerous drugs exhibiting diverse pharmacological activities (Kittakoop et al., 2014). Alkaloids have yielded several significant pharmaceutical compounds as shown in Table 14.1. ...
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