1816 and Serturner
In 1816, the German pharmacist Friedrich Sertürner isolated a substance from opium that he named "morphium", later known as morphine. This discovery marked a significant advancement in pain management, as morphine became the first effective analgesic for severe pain relief. Sertürner's work laid the foundation for the development of modern painkillers and revolutionized medical treatment for patients suffering from acute and chronic pain. He isolated the molecule of morphine, which we can safely qualify as one of the major pharmacochemistry discoveries, one that would have the utmost impact on medecine. But morphine wasn't enough. It felt good, but it made you addicted. It was also found to be dangerous on its own as a respiratory depressant. A century passed by and we can pick up the works of Eisleb and Schauman, 1939 as an exemple, because they discovered pethidine. Pethidine was synthetic, easy to synthesize, and effective (although its primary reason for development was for a spasmolytic usage). The same pattern happened when ketobemidone was discovered by Kirchoff, 1948, also as a spamolytic.