C17H21NO4

COCAINE  , an alkaloid occurring to the extent of about 1% in the leaves of Erythroxylon coca (see above) . It is associated with many other alkaloids: cinnamyl cocaine, C19H23NO4; a-truxilline (C19H23N04)2; /3-truxilline, (C19H23N04)2; benzoylecgonine, C,6H,9NO2; tropa-cocaine, C13H19NO2; hygrine, C8H15NO; cuscohygrine, C,3H24NO2 . These substances, which may be collectively termed " cocaines," are all derivatives of ecgonine (q.v.) . Cocaine is benzoylmethyl ecgonine . It crystallizes from alcohol in prisms, which are sparingly soluble in water . Its solution has a bitter taste, alkaline reaction, and is laevorotatory . Its use as a local anaesthetic (see ANAESTHESIA) makes it the most valuable of the coca alkaloids, and it is much used in ophthalmic practice . Applied to the conjunctiva it causes anaesthesia, dilatation of the pupil, diminution of the intraocular tension, and some interference with accommodation . The conversion of the mixture obtained by extracting coca-leaves into cocaine is effected by saponifying the esters into ecgonine and the respective acids, and then benzoylating and methylating the ecgonine . Homologues of cocaine—ethylbenzoylecgonine, &c.— have been prepared; they closely resemble natural cocaine . Cinnamyl cocaine is cinnamylmethylecgonine, i.e. cocaine in which the benzoyl group is replaced by the cinnamyl group. a- and fl-truxillines, named from their isolation from a coca of Truxillo .(Peru), are two isomeric alkaloids which hydrolyse to ecgonine, methyl alcohol, and two isomeric acids, the truxillic acids, C18H1604 . T'he alkaloids are therefore methyl truxillylecgonines .

The truxillic acids have been studied by K .

Liebermann and his students (Ber., vols . 21-27, and 31), and are diphenyl tetra-methylene dicarboxylic acids .