(4) Isoquinoline group. The opium alkaloids: morphine, codeine, thebaine, papaverine, narcotine, narceine, &c.; and the complicated substances hydrastine and berberine.
A second paper, published in 1817, was followed in the same year by the identification of a new base, narcotine, by P. J.
The alkaloids fall into two chemical groups: (i) derivatives of isoquinoline, including papaverine, narcotine, gnoscopine (racemic narcotine), narceine, laudanosine, laudanine, cotarnine, hydrocotarnine (the last two do not occur in opium), and (2) derivatives of phenanthrene, including morphine, codeine, thebaine.
Narcotine, C22H23N07, has been principally investigated by A.
Narcotine was shown to be methoxyhydrastine (II.) (hydrastine, the alkaloid of Golden seal, Hydrastis canadensis, was solved by E.
Narceine, C23H27N08, obtained by the action of potash on the methyl iodide of narcotine, is probably IV.
Of the other alkaloids narceine is hypnotic, like morphine and codeine, whilst thebaine, papaverine and narcotine have an action which resembles that of strychnine, and is, generally speaking, undesirable or dangerous if at all well marked.
By this process of preparation a considerable portion of the narcotine, caoutchouc, resin, oil or fatty and insoluble matters are removed, and the prolonged boiling, evaporating and baking over a naked fire tend to lessen the amount of alkaloids present in the extract.
Morphine and the other opium alkaloids (codeine, narcotine, laudanine, &c.) have two prominent actions - a narcotic followed by a tetanic action.