Dictamnine and Related Quinoline Alkaloids from Dictamnus: From Phytochemistry to Biological Activities and Toxicity

Quinoline alkaloids constitute an important and structurally diverse class of secondary metabolites occurring in the genus Dictamnus. Among these compounds, dictamnine is the most extensively investigated alkaloid. This review summarizes the phytochemical diversity, structural features, and biosynthetic aspects of Dictamnus quinoline alkaloids, with particular emphasis on the biological, pharmacological, pharmacokinetic, and toxicological properties of dictamnine. Dictamnine has been investigated for its anti-inflammatory, anticancer, antimicrobial, antifeedant, and vasorelaxant effects, involving multiple molecular and cellular mechanisms. Other quinoline alkaloids also exhibit diverse biological activities; however, their pharmacological properties and mechanisms of action remain considerably less characterized than those of dictamnine. Importantly, the biological effects of these compounds should be evaluated in the context of their safety and toxicological profiles. This review provides an overview of the current knowledge of Dictamnus quinoline alkaloids and highlights the need for further studies addressing their mechanisms of action, pharmacokinetic properties, and safety.