Terpenes are a class of natural products consisting of compounds with the formula (C5H8)n for n ≥ 2. Terpenes are major biosynthetic building blocks. Comprising more than 30,000 compounds, these unsaturated hydrocarbons are produced predominantly by plants, particularly conifers. In plants, terpenes and terpenoids are important mediators of ecological interactions, while some insects use some terpenes as a form of defense. Other functions of terpenoids include cell growth modulation and plant elongation, light harvesting and photoprotection, and membrane permeability and fluidity control.
Bilobalide is a biologically active terpenic trilactone present in Ginkgo biloba.
Prenylation is the addition of hydrophobic molecules to a protein or a biomolecule. It is usually assumed that prenyl groups (3-methylbut-2-en-1-yl) facilitate attachment to cell membranes, similar to lipid anchors like the GPI anchor, though direct evidence of this has not been observed. Prenyl groups have been shown to be important for protein–protein binding through specialized prenyl-binding domains.
Farnesyl pyrophosphate (FPP), also known as farnesyl diphosphate (FDP), is an intermediate in the biosynthesis of terpenes and terpenoids such as sterols and carotenoids. It is also used in the synthesis of CoQ, as well as dehydrodolichol diphosphate.
Geranylgeranyl pyrophosphate is an intermediate in the biosynthesis of diterpenes and diterpenoids. It is also the precursor to carotenoids, gibberellins, tocopherols, and chlorophylls.
Sesquiterpenes are a class of terpenes that consist of three isoprene units and often have the molecular formula C15H24. Like monoterpenes, sesquiterpenes may be cyclic or contain rings, including many unique combinations. Biochemical modifications such as oxidation or rearrangement produce the related sesquiterpenoids. A recent study conducted in the Cosmics Leaving Outdoor Droplets large cloud chamber at CERN, has identified sesquiterpenes—gaseous hydrocarbons that are released by plants—as potentially playing a major role in cloud formation in relatively pristine regions of the atmosphere.
Andrographolide is a labdane diterpenoid that has been isolated from the stem and leaves of Andrographis paniculata. Andrographolide is an extremely bitter substance.
Squalene synthase (SQS) or farnesyl-diphosphate:farnesyl-diphosphate farnesyl transferase is an enzyme localized to the membrane of the endoplasmic reticulum. SQS participates in the isoprenoid biosynthetic pathway, catalyzing a two-step reaction in which two identical molecules of farnesyl pyrophosphate (FPP) are converted into squalene, with the consumption of NADPH. Catalysis by SQS is the first committed step in sterol synthesis, since the squalene produced is converted exclusively into various sterols, such as cholesterol, via a complex, multi-step pathway. SQS belongs to squalene/phytoene synthase family of proteins.
In enzymology, a geranyltranstransferase is an enzyme that catalyzes the chemical reaction
Carotol was first isolated by scientists Asahina and Tsukamoto in 1925. It is one of the primary components found in carrot seed oil comprising approximately 40% of this essential oil. This sesquiterpene alcohol is thought to be formed in carrot seeds during the vegetation period. Additionally, studies have shown that carotol may be involved in allelopathic interactions expressing activity as an antifungal, herbicidal and insecticidal agent.
Absinthin is a naturally produced triterpene lactone from the plant Artemisia absinthium (Wormwood). It constitutes one of the most bitter chemical agents responsible for absinthe's distinct taste. The compound shows biological activity and has shown promise as an anti-inflammatory agent, and should not be confused with thujone, a neurotoxin also found in Artemisia absinthium.
Juvabione, historically known as the paper factor, is the methyl ester of todomatuic acid. Both are sesquiterpenes (C15) found in the wood of true firs of the genus Abies. They occur naturally as part of a mixture of sesquiterpenes based upon the bisabolane scaffold. Sesquiterpenes of this family are known as insect juvenile hormone analogues (IJHA) because of their ability to mimic juvenile activity in order to stifle insect reproduction and growth. These compounds play important roles in conifers as the second line of defense against insect induced trauma and fungal pathogens.
Merrilactone A is one of the four sesquiterpenes that were newly discovered from the fruit of Illicium merrillianum in 2000. Members of the genus Illicium include Chinese star anise, widely used as a spice for flavouring food and beverages, and also poisonous plants such as Japanese star anise. Chemical studies of Illicium have developed rapidly over the last 20 years, and merrilactone A has been shown to have neurotrophic activity in fetal rat cortical neuron cultures. This has led researchers to believe that Merrilactone A may hold therapeutic potential in the treatment of neuro-degenerative diseases such as Alzheimer's disease and Parkinson's disease.
(+)-Costunolide is a naturally occurring sesquiterpene lactone, first isolated in Saussurea costus roots in 1960. It is also found in lettuce.
Withaferin A is a steroidal lactone, derived from Acnistus arborescens, Withania somnifera and other members of family Solanaceae. It is the first member of the withanolide class of ergostane type product to be discovered.
Verrucarin A is a chemical compound that belongs in the class of trichothecenes, a group of sesquiterpene toxins produced by several fungi, namely from the Fusarium species, that are responsible for infecting food grains. It was first described in 1962. Within the skeleton of the basic trichothecene structure, the olefin and epoxide are crucial for toxicity; ester functionalities and hydroxyl groups often contribute to the toxicity, thereby rendering verrucarin A as one of the most lethal examples. The mechanism of action for this class of toxins mainly inhibits protein biosynthesis by preventing peptidyl transferase activity. Although initially thought to be potentially useful as anticancer therapeutics, numerous examples of trichothecene derivatives were shown to be too toxic for clinical use.
Cynaropicrin is a sesquiterpene lactone of the guaianolide type found mainly in leaves of artichoke plants. It is one of the compounds that gives the artichoke its characteristic bitterness. It is found in artichoke leaves with an abundance of approximately 87 g/kg, but can hardly be found in other parts of the plant. Cynaropicrin makes up about 0.7% of leaf extracts of the artichoke. It exhibits a large diversity of bioactivities and shows properties such as anti-inflammatory, antifeedant and activation of bitter sensory receptors, but has not yet been used in medicine. Despite its pharmacologically beneficial properties, it can be toxic in higher doses. The compound has attracted attention in recent years as a potential anticancer drug.
In organic chemistry, a guaianolide is a type of sesquiterpene lactone consisting of a gamma-lactone and either a cyclopentane or cyclopentene, both fused to a central cycloheptane or cycloheptene structure. There are two subclasses, structural isomers differing in the location that part of the lactone is bonded to the central ring, known as 6,12-guaianolides and 8,12-guaianolides.
Avarol is a hydroquinone first isolated from the Mediterranean marine sponge Dysidea avara 1974 Avarol represented the first sesquiterpenoid with a rearranged drimane skeleton and its structure was established by standard analytical methods, chemical degradation and later by stereocontrolled synthesis. Intrigued by the wide range of biological activities of this metabolite, Avarol has inspired the development of many synthetic derivatives and the study of their applications.
Xanthatin, or (3aR,7S,8aS)-7-methyl-3-methylidene-6-[(E)-3-oxobut-1-enyl]-4,7,8,8a-tetrahydro-3aH-cyclohepta[b]furan-2-one (C15H18O3) is a major bioactive compound found in the leaves of the Xanthium strumarium (Asteracae) plant. It is classified as a natural sesquiterpene lactone. Xanthatin is believed to have anti-inflammatory, anti-tumour, anti-microbial, and anti-parasitic properties hence it is being researched for potential use in treatment of cancer and autoimmune diseases. While it has been used in traditional medicine for decades, its mechanisms and modern use haven’t been fully understood yet.
