The terpenoids, sometimes referred to as isoprenoids, are a large and diverse class of naturally occurring organic chemicals similar to terpenes, derived from five-carbon isoprene units assembled and modified in thousands of ways. Most are multicyclic structures which differ from one another not only in functional groups, but also in their basic carbon skeletons. These lipids can be found in all classes of living things, and are the largest group of natural products. Benzene An organic compound is any member of a large class of chemical compounds whose molecules contain carbon, with the exception of carbides, carbonates, carbon oxides and elementary carbon. ... Terpenes are a large and varied class of hydrocarbons, produced primarily by a wide variety of plants, particularly conifers, though also by some animals. ... Isoprene is a common synonym for the chemical compound 2-methyl-1,3-butadiene. ... In organic chemistry functional groups are specific groups of atoms within molecules, that are responsible for the characteristic chemical reactions of those molecules. ... Lipids are a class of hydrocarbon-containing organic compounds essential for the structure and function of living cells. ...

Plant terpenoids are extensively used for their aromatic qualities. They play a role in traditional herbal remedies and are under investigation for antibacterial, antineoplastic and other pharmaceutical effects. Terpenoids contribute to the scent of eucalyptus, the flavors of cinnamon, cloves and ginger and the color of yellow flowers. Well-known terpenoids include citral, menthol, camphor and the cannabinoids found in the Cannabis plant. Species About 700; see the List of Eucalyptus species Wikispecies has information related to: Eucalyptus hello gemma ere wuu2????Eucalyptus is a diverse genus of trees (rarely shrubs), the members of which dominate the tree flora of Australia. ... Binomial name Cinnamomum verum J.Presl Cassia (Indonesian cinnamon) is also commonly called (and sometimes sold as) cinnamon. ... This article is about spices, the word clove is also used to describe a segment of a head of garlic and a clove hitch is a useful kind of knot. ... Binomial name Zingiber officinale Roscoe Ginger root is used extensively as a spice in many if not most cuisines of the world. ... Citral or 3,7-dimethylocta-2,6-dien-1-al or lemonal C10H16O is a chemical compound and part of the terpene family. ... Menthol is a covalent organic compound made synthetically or obtained from peppermint or other mint oils. ... R-phrases 11-20/21/22-36/37/38 S-phrases 16-26-36 RTECS number EX1260000 (R) EX1250000 (S) Supplementary data page Structure and properties n, εr, etc. ... Cannabinoids are a group of chemicals which activate the bodys cannabinoid receptors. ... Species Cannabis indica Cannabis ruderalis Cannabis sativa This is one of several related articles about cannabis. ...

The steroids and sterols in animals are biologically produced from terpenoid precursors. Sometimes terpenoids are added to proteins, e.g. to enhance their attachment to the cell membrane; this is known as isoprenylation. A steroid is a lipid characterized by a carbon skeleton with four fused rings. ... Sterols, or steroid alcohols are a subgroup of steroids with a hydroxyl group in the 3-position of the A-ring. ... A representation of the 3D structure of myoglobin, showing coloured alpha helices. ... Drawing of a cell membrane A component of every biological cell, the selectively permeable cell membrane (or plasma membrane or plasmalemma) is a thin and structured bilayer of phospholipid and protein molecules that envelopes the cell. ... Prenylation or isoprenylation is the addition of hydrophobic molecules to a protein to facilitate its attachment to the cell membrane. ...

Structure and classification

Terpenes are hydrocarbons resulting from the combination of several isoprene units. Terpenoids can be thought of as modified terpenes, where methyl groups have been moved or removed, or oxygen atoms added. (Some authors use the term "terpene" more broadly, to include the terpenoids.) Just like terpenes, the terpenoids can be classified according to the number of isoprene units used: Terpenes are a large and varied class of hydrocarbons, produced primarily by a wide variety of plants, particularly conifers, though also by some animals. ... Hydrocarbons are refined at oil refineries and processed at chemical plants In chemistry, a hydrocarbon is any chemical compound that consists only of the elements carbon (C) and hydrogen (H). ... Isoprene is a common synonym for the chemical compound 2-methyl-1,3-butadiene. ... In chemistry a methyl-group is a hydrophobic Alkyl functional group which is derived from methane (CH4). ... General Name, Symbol, Number oxygen, O, 8 Chemical series Nonmetals, chalcogens Group, Period, Block 16, 2, p Appearance colorless Atomic mass 15. ...

• Monoterpenoids, 2 isoprene units
• Sesquiterpenoids, 3 isoprene units
• Diterpenoids, 4 isoprene units
• Sesterterpenoids, 5 isoprene units
• Triterpenids, 6 isoprene units
• Tetraterpenoids, 8 isoprene units
• Polyterpenoids with a larger number of isoprene units

Terpenoids can also be classified according to the number of cyclic structures they contain.

Biosynthesis

There are two metabolic pathways of creating terpenoids: In biochemistry, a metabolic pathway is a series of chemical reactions occurring within a cell, catalyzed by enzymes, to achieve in either the formation of a metabolic product to be used or stored by the cell, or the initiation of another metabolic pathway (then called a flux generating step). ...

Mevalonic acid pathway

Many organisms manufacture terpenoids through the HMG-CoA reductase pathway, the pathway that also produces cholesterol. The reactions take place in the cytosol. The pathway was discovered in the 1950s. The HMG-CoA reductase pathway, also known as MVA pathway or mevalonate-dependent (MAD) route, is an important cellular metabolic pathway present in virtually all organisms. ... Cholesterol is a sterol (a combination steroid and alcohol) and a lipid found in the cell membranes of all body tissues, and transported in the blood plasma of all animals. ... ÃThe cytosol (as opposed fatty cytoplasm, which also includes the organelles) is the internal fluid of the cell, and a large part of cell metabolism occurs here. ... The 1950s were the decade that spanned the years 1950 through 1959, although some sources say from 1951 through 1960. ...

MEP/DOXP pathway

The MEP/DOXP pathway, also known as 2-C-methyl-D-erythritol 4-phosphate/deoxy-xylulose phosphate pathway or mevalonic acid independent pathway takes place in the plastids of plants. It was discovered in the late 1980s. Mevalonic acid is a key organic compound in biochemistry. ... Plastids are major organelles found only in plants and algae. ...

Pyruvate is converted by DOXP synthase (DXS) to 1-Deoxy-D-xylulose-5-P and by DOXP reductase (DXR) to 2-C-Methyl-D-erythritol-4-P (MEP) and in multiple steps to isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP). Pyruvate (CH3COCOO−) is the ionized form of pyruvic acid. ... Chemical structure of isopentenyl pyrophosphate. ... Structure of dimethyallyl pyrophosphate Dimethylallyl pyrophosphate (or -diphosphate) (DMAPP) is an intermediate product of both mevalonic acid (MVA) pathway and DOXP/MEP pathway. ...

DMAPP is a common metabolite in both pathways and an exchange of DMAPP would be possible.

Out of this intermediate, isoprene, monoterpenoids (10-carbon) diterpenoids (20-carbon), carotenoids (40-carbon), chlorophylls and plastoquinone-9 (45-carbon) are formed. Isoprene is a common synonym for the chemical compound 2-methyl-1,3-butadiene. ... Carotenoids are organic pigments that are naturally occurring in plants and some other photosynthetic organisms like algae, some types of fungus and some bacteria. ... Chlorophyll is a green photosynthetic pigment found in plants, algae, and cyanobacteria. ... Plastoquinone Plastoquinone, often abbreviated pq, is a molecule used in the electron transport chain in the light-dependent reactions of photosynthesis. ...

Intermediates are geranyl pyrophosphate (GPP) and geranylgeranyl pyrophosphate (GGPP). Both intermediates can also be found in the MVA pathway. Chemical structure of geranyl pyrophosphate. ... Chemical structure of geranylgeranyl pyrophosphate. ...

Although both pathways, MVA and MEP, operate independently under normal conditions, interactions between them have been reported repeatedly.

Phyla/Divisions Actinobacteria Aquificae Bacteroidetes/Chlorobi Chlamydiae/Verrucomicrobia Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Nitrospirae Omnibacteria Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Bacteria is also the fictional name of a warring nation under Benzino Napaloni as dictator, in the 1940 film The Great Dictator... Phyla / Classes Phylum Crenarchaeota Phylum Euryarchaeota     Halobacteria     Methanobacteria     Methanococci     Methanopyri     Archaeoglobi     Thermoplasmata     Thermococci Phylum Korarchaeota Phylum Nanoarchaeota The Archaea (; from Greek αρχαία, old ones; singular Archaeum, Archaean, or Archaeon), also called Archaebacteria (), are a major division of living organisms. ... A seaweed (Laurencia) up close: the branches are multicellular and only about 1 mm thick. ... Divisions Land plants (embryophytes) Non-vascular plants (bryophytes) Marchantiophyta - liverworts Anthocerotophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) Lycopodiophyta - clubmosses Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongues Seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta - flowering plants Adiantum pedatum (a fern... Phyla Animals are a major group of organisms, classified as the kingdom Animalia or Meta­zoa. ... Divisions Chytridiomycota Zygomycota Ascomycota Basidiomycota The Fungi (singular: fungus) are a large group of organisms ranked as a kingdom within the Domain Eukaryota. ...

See Also

• Pharmacology

Pharmacology (in Greek: pharmacon (φάρμακον) meaning drug, and logos (λόγος) meaning science) is the study of how chemical substances interact with living systems. ...

External link

• IUPAC nomenclature of terpenoids