Development of 5-Substituted <i>N</i>-Methylmorphinan-6-ones as Potent Opioid Analgesics with Improved Side-Effect Profile

<table>Preparation of 14-methoxymetopon (<b>13</b>), 14-ethoxymetopon (<b>14</b>), and 5-benzyl-14-<i>O</i>-methyloxymorphone (<b>15</b>).</table>

International Journal of Medicinal Chemistry

Scheme 1: Development of 5-Substituted <i>N</i>-Methylmorphinan-6-ones as Potent Opioid Analgesics with Improved Side-Effect Profile 