Three New C19-Diterpenoid Alkaloids from Aconitum novoluridum

Exploring the Biomedical Potential of Terpenoid Alkaloids: Sources, Structures, and Activities

Terpenoid alkaloids are recognized as a class of compounds with limited numbers but potent biological activities, primarily derived from plants, with a minor proportion originating from animals and microorganisms. These alkaloids are synthesized from the same prenyl unit that forms the terpene skeleton, with the nitrogen atom introduced through β-aminoethanol, ethylamine, or methylamine, leading to a range of complex and diverse structures. Based on their skeleton type, they can be categorized into monoterpenes, sesquiterpenes, diterpenes, and triterpene alkaloids. To date, 289 natural terpenoid alkaloids, excluding triterpene alkaloids, have been identified in studies published between 2019 and 2024. These compounds demonstrate a spectrum of biological activities, including anti-inflammatory, antitumor, antibacterial, analgesic, and cardioprotective effects, making them promising candidates for further development. This review provides an overview of the sources, chemical structures, and biological activities of natural terpenoid alkaloids, serving as a reference for future research and applications in this area.

A review on efforts for improvement in medicinally important chemical constituents inAconitum through biotechnological interventions

The genus Aconitum belongs to the family Ranunculaceae, is endowed with more than 350 species on the earth. Medicinally important aconitine type of diterpenoid alkaloids are the characteristic compounds in most of the Aconitum species. The present review endeavored the major research carried out in the field of genetic resource characterization, pharmacological properties, phytochemistry, major factors influencing quantity, biosynthetic pathways and processing methods for recovery of active ingredients, variety improvement, propagation methods, and important metabolite production through cell/organ culture of various Aconitum species. More than 450 derivatives of aconitine-type C19 and C20-diterpenoid alkaloids along with a few other non-alkaloidal compounds, such as phenylpropanoids, flavonoids, terpenoids, and fatty acids, have been identified in the genus. A few Aconitum species and their common diterpenoid alkaloid compounds are also well characterized for analgesic, inflammatory and cytotoxic properties. However, the different isolated compound needs to be validated for supporting other traditional therapeutical uses of the plant species. Aconitine alkaloids shared common biosynthesis pathway, but their diversification mechanism remains unexplored in the genus. Furthermore, the process needs to be developed on secondary metabolite recovery, mass-scale propagation methods, and agro-technologies for maintaining the quality of products. Many species are losing their existence in nature due to over-exploitation or anthropogenic factors; thus, temporal monitoring of the population status in its habitat, and suitable management programs for ascertaining conservation needs to be developed.

Metabolite Profiling of Talatisamine in Heart Tissue After Oral Administration and Analysis of Cardiac Bioactivities

The lateral roots of the Aconitum carmichaelii ("Fuzi") have been used for centuries as a cardiotonic in China. The diterpenoid alkaloid talatisamine (TA) is a major bioactive component of Fuzi, but the identity and bioactivities of the TA metabolites have not been examined in detail. In this study, metabolite profiling of TA was performed in rat heart by UPLC-MS following oral administration. Metabolites were identified by comparing protonated molecules, fragmentation patterns, and chromatographic behaviors with those of standard compounds. Metabolites of TA were then prepared and tested for cardiotonic activity on isolated frog hearts. The metabolite cammaconine, a C₁₉ diterpenoid alkaloid with a hydroxyl group at C-18, exhibited substantial cardiotonic activity during frog heart perfusion. To further investigate the structure-cardiac effect relationships, a series of C₁₉-diterpenoid alkaloids with 18-OH were prepared. Eight tested compounds (5: -12: ) demonstrated measurable cardioactivity, of which compound 5: with an N-methyl group and compound 7: with a methoxy at C-16 showed stronger effects on ventricular contraction than the other compounds. Thus, 18-OH is a critical structural feature determining cardiotonic activity, and efficacy is improved by the presence of N-methyl or methoxy at C-16. Preliminary mechanistic studies suggested that the cardiotonic effect of compound 5: is mediated by enhanced cellular calcium influx. Metabolites of TA with these structural features may be useful therapeutics to prevent heart failure.

Norditerpenoid alkaloids from Aconitum and Delphinium: structural relevance in medicine, toxicology, and metabolism

Covering: 77 A.D. up to 2020Norditerpenoid alkaloids (NDA), typically N-ethylpiperidine containing C19 or C18 natural product diterpenes, are hexacycles with several contiguous often oxygenated stereocentres. As a function of their structural complexity, they display important pharmacological activities. The processed plants are used as important folk drugs and four NDAs have now been clinically approved. Many metabolism studies on Aconitum alkaloids have been reported as the understanding of their biotransformation in living systems and in cell-free systems is important for the development of these alkaloids as drugs. This Highlight sets out the missing links in NDA biosynthesis, their biological applications, SAR, toxicity, metabolism, and analytical studies.