Synthesis and Modification of Morphine and Codeine, Leading to Diverse Libraries with Improved Pain Relief Properties.

Morphine and codeine, two of the most common opioids, are widely used in the clinic for different types of pain. Morphine is one of the most potent agonists for the -opioid receptor, leading to the strongest analgesic effect. However, due to their association with serious side effects such as respiratory depression, constriction, euphoria, and addiction, it is necessary for derivatives of morphine and codeine to be developed to overcome such drawbacks.