Abstract
An undetermined principle has been obtained from poison ivy which so far as I have been able to find differs in its behavior from that of any substance previously described.
It came down as a precipitate after long standing of a filtrate after precipitating with lead acetate.
No work has as yet been done with the substance except to determine a few of its properties.
It is non-irritant when applied to the skin, neutral to litmus and is bitter to the taste. It has a melting point of 190° when heated slowly, insoluble in cold water and fairly soluble on boiling, imparting a lemon yellow color to the solution. It is soluble in ammonia water, acetic acid and hot alcohol. Insoluble in alcohol in the cold, ether, chloroform, petroleum ether and acetone. It gives striking color reactions with H2SO4, HNO3, KOH, CaOH and other reagents.
A solution to which a few drops of silver nitrate are added gives a pink color changing quickly to a dull green.
Iodine as Lugol's solution gives a pink color which quickly fades.
With ferric chloride a very dark blue or black changing to brown.
On the addition of Fehling's solution it turns green and on boiling a slight reduction occurs.
It does not reduce Fehling's solution in the cold on long standing even after it had been previously boiled with acid and again rendered neutral. This leads to doubt as to its being a glucoside.
With Millon's reagent it turns a port-wine color rapidly becoming darker which suggest the possibility of its belonging in the group of the phenols.
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