Thebaine (TB)

Thebaine is an opiate alkaloid, A minor constituent of opium, thebaine is chemically similar to both morphine and codeine, but has stimulatory rather than depressant effects. At high doses, it causes convulsions similar to strychnine poisoning. The "unnatural" enantiomer (+)-thebaine does show analgesic effects apparently mediated through opioid receptors, unlike the inactive natural enantiomer (-)-thebaine.

Thebaine is not used therapeutically, but as the main alkaloid extracted from Papaver bracteatum (Iranian poppy), it can be converted industrially into a variety of compounds including oxycodone, oxymorphone, nalbuphine, naloxone, naltrexone, buprenorphine and etorphine. This alkaloid is biosynthetically related to salutaridine, oripavine, morphine and reticuline.