Principium somniferum

Since the seminal work of Sertiirner, there were substantial efforts to elucidate the chemical structure of the principium somniferum. 

In 1805 Sertiirner obtained an acid (meconic acid) by precipitating extract of opium made with ammonia with lead acetate or baryta water, and decomposing the precipitate with sulphuric acid. He found that the acid gave a red colour with ferric chloride. In a confused account he stated that opium also contains a crystalline substance forming salts with acids, which in opium is probably combined with meconic acid (Mohnsaure, Opiumsaure) the substance had narcotic properties and he called it principium somniferum . He concluded by saying that he saw Derosne s paper only when his research was... 

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