29 y/o M was complaining of a headache and collapsed instantly. EMS was named and resuscitation was unsuccessful. dimethylamino team drastically improves the MOR affinity, as in U-47700. In contrast, embedding that same simple nitrogen right into a cyclic pyrrolidine ring considerably improves the KOR affinity, as in U-50488. MOR/KOR https://prosyntheticchems.com/product/u-48800/