Phorbol is a natural, plant-derived organic compound

Organic compound

An organic compound is any member of a large class of gaseous, liquid, or solid chemical compounds whose molecules contain carbon. For historical reasons discussed below, a few types of carbon-containing compounds such as carbides, carbonates, simple oxides of carbon, and cyanides, as well as the...

. It is a member of the tigliane family of diterpenes

Terpene

Terpenes are a large and diverse class of organic compounds, produced by a variety of plants, particularly conifers, though also by some insects such as termites or swallowtail butterflies, which emit terpenes from their osmeterium. They are often strong smelling and thus may have had a protective...

. It was first isolated in 1934 as the hydrolysis

Hydrolysis

Hydrolysis is a chemical reaction during which molecules of water are split into hydrogen cations and hydroxide anions in the process of a chemical mechanism. It is the type of reaction that is used to break down certain polymers, especially those made by condensation polymerization...

 product of croton oil

Croton oil

Croton oil is an oil prepared from the seeds of Croton tiglium, a tree belonging to the natural order Euphorbiales and family Euphorbiaceae, and native or cultivated in India and the Malay Archipelago. Small doses taken internally cause diarrhea. Externally, the oil can cause irritation and swelling...

, which is derived from the seeds of Croton tiglium

Croton tiglium

Croton tiglium, known as Purging Croton, is a plant species in the Euphorbiaceae family.-Medicinal uses:It is one of the 50 fundamental herbs of used in traditional Chinese medicine, where it has the name bā dòu ....

. Phorbol's structure was determined in 1967. It is very soluble in most polar organic solvents, as well as in water.

Various ester

Ester

Esters are chemical compounds derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol. Esters are usually derived from an inorganic acid or organic acid in which at least one -OH group is replaced by an -O-alkyl group, and most commonly from carboxylic acids and...

s of phorbol have important biological properties, the most notable of which is the capacity to act as tumor promoters through activation of protein kinase C

Protein kinase C

Protein kinase C also known as PKC is a family of enzymes that are involved in controlling the function of other proteins through the phosphorylation of hydroxyl groups of serine and threonine amino acid residues on these proteins. PKC enzymes in turn are activated by signals such as increases in...

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