“Historically, laboratory synthesis of cannabinoids were often based on the structure of herbal cannabinoids, and a large number of analogs have been produced and tested, especially in a group led by Roger Adams as early as 1941 and later in a group led by Raphael Mechoulam.

Newer compounds are no longer related to natural cannabinoids or are based on the structure of the endogenous cannabinoids.

Synthetic cannabinoids are particularly useful in experiments to determine the relationship between the structure and activity of cannabinoid compounds, by making systematic, incremental modifications of cannabinoid molecules.

Medications containing natural or synthetic cannabinoids or cannabinoid analogs:

• Dronabinol (Marinol), is Δ⁹-tetrahydrocannabinol (THC), used as an appetite stimulant, anti-emetic, and analgesic
• Nabilone (Cesamet), a synthetic cannabinoid and an analog of Marinol. It is Schedule II unlike Marinol, which is Schedule III
• Sativex, a cannabinoid extract oral spray containing THC, CBD, and other cannabinoids used for neuropathic pain and spasticity in Canada and Spain. Sativex develops whole-plant cannabinoid medicines
• Rimonabant (SR141716), a selective cannabinoid (CB₁) receptor antagonist used as an anti-obesity drug under the proprietary name Acomplia. It is also used for smoking cessation

Other notable synthetic cannabinoids include:

• CP-55940, produced in 1974, this synthetic cannabinoid receptor agonist is many times more potent than THC
• Dimethylheptylpyran
• HU-210, about 100 times as potent as THC
• HU-331 a potential anti-cancer drug derived from cannabidiol that specifically inhibits topoisomerase II.
• SR144528, a CB₂ receptor antagonists
• WIN 55, a potent cannabinoid receptor agonist
• JWH-133, a potent selective CB₂ receptor agonist
• Levonantradol (Nantrodolum), an anti-emetic and analgesic but not currently in use in medicine”

http://www.news-medical.net/health/Synthetic-and-Patented-Cannabinoids.aspx