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XVIII. Onthe Constitution of Quinine, J5y Adolph Strecker*. 



NOTWITHSTANDING the great importance of quinine, it 

 is much less perfectly known to chemists than a multi- 

 tude of compounds which possess no interest in a practical point 

 of view. In fact, chemists are agreed neither as to its elementary 

 composition, its equivalent, nor its molecule ; and we are still 

 further from being acquainted with the constitution of this alka- 

 loid. It is clear, therefore, that before we shall be able to com- 

 pose quinine, these preliminary' questions must be resolved ; and 

 I think that by publishing my researches, I may perhaps assist 

 those chemists who wish to see the solution of the problem of 

 the artificial production of quinine. 



The elementary composition of quinine is expressed at present 

 by the formulse C^^ H^^ NO^ (Laurent) or C^o H^^i^O^ (Liebig). 

 This is a question which may readily be settled by the analysis 

 of pure quinine. I prepared this base in a state of purity from 

 commercial sulphate of quinine, which I obtained through M. 

 Merck in an extremely pure state, and purified still further by 

 repeated crystallizations. The analysis of quinine, dried at 

 248° F., was effected with oxide of copper and oxygen gas ; it 

 gave me the formula C^^H^^NO^,or in per-centage proportions, — 



Found. Calculated. 



Carbon . . . 74-0 74-1 74-1 



Hydrogen . . 7*5 7*5 7*4 



Nitrogen ... 8*6 



Oxygen . . . 9'9 



This formula is also confirmed by the analysis of several of its 

 compounds. 



Nitrate of Quinine. — Sulphate of quinine precipitated by ni- 

 trate of baryta and left to spontaneous evaporation furnishes 

 colourless rhombic crystals. The analysis of this compound, 

 when purified by several crystallizations, led to the formula 

 C40 H24 N2 0^ . HO . N0^ or in a hundred parts,— 



Found. Calculated. 



Carbon .... 62-1 620 



Hydi'ogen . . . 6'6 6*5 



Sulphate of Quinine. — The sulphate from which I prepared 

 the quinine, after drying at 248° F., furnished 10*7 and 10-8 

 per cent, of sulphuric acid, numbers which are almost identical 

 with those calculated from the formula 



C40 H24 ^2 04 . HO . SO^ (calculation 10-7 per cent. SO^). 

 An alcoholic solution of quinine furnishes with nitrate of 

 * From the Comptes Rendus, July 3, 1854, p. 58. 



