FoundationalConceptsNeuroscience

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Morphine Diacetylmorphine

Diacetylmorphine was found to be about twice as potent as
morphine in its physiological effects in humans. The increased po-
tency is now understood to be due to its more efficient entry into
the brain—acetyl groups are less polar than hydroxyl groups, so
diacetylmorphine crosses the blood-brain barrier more efficiently
than does morphine. Diacetylmorphine was the first of anumber of
semisynthetic opioids (chemicals having opium-like effects in the
body) that were developed. During the twentieth century, a number of
chemical derivatives of morphine were synthesized by pharmaceuti-
cal companies and marketed under various brand names, for example,
hydrocodone (Vicodin), hydromorphone (Dilaudid), and oxycodone
(Oxy-Contin, Percodan, Percocet).
In the early years of World War II, German chemists developed the
drug methadone, the first instance of a completely synthetic opioid.