Tetrahydrocannabinol, also known as delta-9-tetrahydrocannabinol, is the principal psychoactive constituent of the cannabis plant. First isolated in 1964, in its pure form, by Israeli scientists Raphael Mechoulam, Yechiel Gaoni and colleagues at the Hebrew University of Jerusalem, it is a glassy solid when cold, and becomes viscous and sticky if warmed. A pharmaceutical formulation of THC, known by its INN dronabinol, is available by prescription in the U.S. and Canada under the brand name Marinol. An aromatic terpenoid, THC has a very low solubility in water, but good solubility in most organic solvents, specifically lipids and alcohols. Like most pharmacologically-active secondary metabolites of plants, THC in cannabis is assumed to be involved in self-defense, perhaps against herbivores. THC also possesses high UV-B absorption properties, which, it has been speculated, could protect the plant from harmful UV radiation exposure. Wikipedia [ - ]

Tetrahydrocannabinol, also known as delta-9-tetrahydrocannabinol, is the principal psychoactive... [ + ]