C8H15NO

TROPINE  , a base formed together with tropic acid, C9H1003, in the hydrolysis of the alkaloid atropine (K . Kraut, Ann., 1863, 128, p . 28o; 1865, 133, p . 87) . It crystallizes in plates which melt at 63° C. and boil at 233° C.; it is very hygroscopic and easily soluble in water . It is an optically inactive, strongly alkaline tertiary base . On heating with sodium in amyl alcoholic solution it it sransformed into a stereo-isomer, identical with the '-tropine obtained by hydrolysing tropa-cocaine with hydrochloric acid . It possesses alcoholic properties, since it forms esters, the so-called " tropeines." On distillation with caustic baryta or soda lime it decomposes into methylamine and tropilidine, C7H8 (A . Ladenburg, Ann . 1883, 217, p . 74), the same hydrocarbon being also obtained when it is destructively methylated, a certain amount of tropiline, C7H100, being produced simultaneously When heated with fuming hydrochloric acid to 150--18o° C. it yields tropidine, C3H13N, and with hydriodic acid 'similarly forms an 3 A fourth species, P. indieus, has been described from the Gulf of Oman, but doubt has been expressed as to its validity (Legge, PP . 1173, 1174) .

' Sulidae (

Gannet), Pelecanidae (Pelican), Plotidae (Snake-bird) . Phalacrocoracidae (Cormorant,) and Fregatidae (Frigate-bird) . iodo-compound, C8H15NI2, which, on reduction with zinc and hydrochloric acid, is converted into hydrotropidine, C8H15N . It yields various oxidation products . With an alkaline solution of potassium permanganate it yields tropigenine, C7H13NO; with chromic acid in the presence of acetic acid it yields tropinone, C8H13NO; and with chromic acid in the presence of sulphuric acid it yields tropinic acid, C6H11N(CO2H)2 . Tropidine, C8H13N, is a liquid having an odour resembling that of confine . It is a strong tertiary base, and is an unsaturated compound, forming addition products with the halogen acids . Hydrotropidine, C8H15N, is also a liquid . Its hydrochloride on distillation loses methyl chloride and yields norhydrotropidine, C7H13N, a compound which is a secondary base, and whose hydro-chloride when distilled over zinc dust yields a-ethylpyridine . Tropinic acid, C6H11N(CO2H)2, obtained as above, is inactive; it was resolved by J . Gadamer (Arch . Pharm., 1901, 239, p .

663) by means of its cinchonine

salt . It is a dibasic acid, and the methiodide of its dimethyl ester on fusion with caustic alkalis yields n-adipic acid . It is apparently a derivative of N—methyl pyrrollidine, since it may be oxidized ultimately to N—methyl succinimide . Tropigenine, C7H13NO, is a secondary base . The most important of the oxidation products of tropine is tropinone, C3H13NO, which is a ketone containing the grouping --CH2•CO•CH2—since it yields a di-isonitroso derivative, a dibenzal derivative, and also forms mono- and di-oxalic esters . It is a strong base and has a powerful reducing action . Its constitution is determined by the above facts and also because tropinic acid on destructive methylation yields a diolefine dicarboxylic acid which on reduction is converted into n-pimelic acid . These data point to tropine possessing an unbranched chain of seven carbon atoms and Incidentally determine the constitution of the other various oxidation products, &c . (R . Willstatter, Ber., 1895-1901) .