Terpenoids with Special Pharmacological Significance: A Review

Abstract

Terpenoids are a very prominent class of natural compounds produced in diverse genera of plants, fungi, algae and sponges. They gained significant pharmaceutical value since prehistoric times, due to their broad spectrum of medical applications. The fragrant leaves of Eucalyptus trees are a rich source of terpenoids. Therefore this review starts by summarizing the main terpenoid compounds present in Eucalyptus globulus, E. citriodora, E. radiata and E. resinifera and describing their biosynthetic pathways. Of the enormous number of pharmaceutically important terpenoids, this paper also reviews some well established and recently discovered examples and discusses their medical applications. In this context, the synthetic processes for (-)-menthol, (-)-cis-carveol, (+)-artemisinine, (+)-merrilactone A and (-)-sclareol are presented. The tricyclic sesquiterpene (-)-englerin A isolated from the stem bark of the Phyllanthus engleri plant (Euphorbiaceae) is highly active against certain renal cancer cell lines. In addition, recent studies showed that englerin A is also a potent and selective activator of TRPC4 and TRPC5 calcium channels. These important findings were the motivation for several renowned research labs to achieve a total synthesis of (-)-englerin A. Two prominent examples-Christmann and Metz-are compared and discussed in detail.

Phytochemicals as Antiviral Agents: Recent Updates

“…Terpenoids, also called as isoprenoids are natural compounds present in plants and have a significant role in pharmaceuticals, therapeutics, and herbal treatments. Terpenoids like diterpenoids, sesquiterpenoids, and triterpenoids have wide variety of application in the area of medicine (Jaeger and Cuny 2016;Perveen and Al-Taweel 2018). Kazakova et al (2018) studied the antiviral activity of betulin and dihydroquinopimaric acid derivatives against influenza A virus (H7N1), HSV type 1, nonenveloped RNA virus (ECHO 6), and HIV type 1.…”

Terpenoids as Potential Geroprotectors

“…All terpenes and terpenoids contain a hydrocarbon skeleton, which is formed from five-carbon precursors (isopentenyl diphosphate and dimethylallyl diphosphate) and polymerizes with the formation of prenyl diphosphates of various lengths. As a result of the removal of the diphosphate group, the intermediate allyl cations can be subjected to a series of chemical cascades with the formation of various compounds with linear and/or cyclized hydrocarbon chains, which are then further modified by the addition of various functional groups and adducts [ 2 , 3 , 4 ]. This feature of terpenes and terpenoids creates their remarkable chemical diversity and requires an appropriate approach for extraction, detection, and purification [ 8 , 9 , 10 ].…”

“…Terpenoids consist of C = 5, 10, 15, 20…, n > 40 carbon units and are classified as hemiterpenes (C5), monoterpenes (C10), sesquiterpenes (C15), diterpenes (C20), triterpenes (C30), tetraterpenes or carotenoids (C40), and polyterpenes (Cn, n > 40) [ 1 ]. Extensive biological investigations revealed a wide range of pharmacological and physiological activities of terpenoids and their derivatives [ 2 , 3 , 4 ]. However, terpenoids are rarely associated with anti-aging properties and may be underestimated as potential geroprotectors.…”

Structure, catalysis, and inhibition mechanism of prenyltransferase

“…Moreover, some of these inhibitors have been assessed in clinical trials. 24,[128][129][130][131][132] Another natural cyclic monoterpenoid, limonene, a major component of fruit-derived essential oils, is a flavoring agent in food manufacturing. Research on its D-form isomer, dlimonene, has progressed to phase one clinical studies for breast, parotid, and submandibular gland cancers (Figure 8c, Tables 1 and 2).…”