1911 Encyclopædia Britannica/Ecgonine
ECGONINE, in chemistry, C9H15NO3, a cycloheptane derivative with a nitrogen bridge. It is obtained by hydrolysing cocaine with acids or alkalis, and crystallizes with one molecule of water, the crystals melting at 198° to 199° C. It is laevo-rotatory, and on warming with alkalis gives iso-ecgonine, which is dextro-rotatory. It is a tertiary base, and has also the properties of an acid and an alcohol. When boiled with caustic baryta it gives methylamine. It is the carboxylic acid corresponding to tropine, for it yields the same products on oxidation, and by treatment with phosphorus pentachloride is converted into anhydroecgonine, C9H13NO2, which, when heated to 280° C. with hydrochloric acid, splits out carbon dioxide and yields tropidine, C8H13N. Anhydroecgonine melts at 235° C., and has an acid and a basic character. It is an unsaturated compound, and on oxidation with potassium permanganate gives succinic acid. It is apparently a tropidine monocarboxylic acid, for on exhaustive methylation it yields cycloheptatriene-1·3·5-carboxylic acid-7. Sodium in amyl alcohol solution reduces it to hydroecgonidine C9H15NO2, while moderate oxidation by potassium permanganate converts it into norecgonine. The presence of the heptamethylene ring in these compounds is shown by the production of suberone by the exhaustive methylation, &c., of hydroecgonidine ethyl ester (see Polymethylenes and Tropine). The above compounds may be represented as:
