Thebaine

Thebaine (C₁₉H₂₃NO₃) is an alkaloid which occurs associated with morphine in opium. It forms small plates with a silvery lustre, which melt at 180°. It is insoluble in water, but is readily dissolved by warm alcohol and by acids. In its chemical constitution it is closely allied to morphine (q.v.), which it resembles also in its chemical behaviour, being, however, much more poisonous.