Combinations of borotungstic acid with nitrogenous compounds

: On combinations of borotungstic acid with nitrogenous compounds. Under definite conditions, these combinations are borotungstates of quinine, cinchonine, cinchonidine, brucine, strychnine, morphine, sparteine, pilocarpine, nicotine, stovaine, procaine, choline and acetylcholine. Their composition is probably variable according to the pH (ex.: procaine).