Chinese Journal of Physiology

72 T. Q. CHOU

tion. When air-dried, it melted below 100°C to a clear colourless liquid, then solidified gradually as the temperature rose and finally melted at 234°C,

(3) Corydalis G.

During the process of purifying Corydalis F by means of its hydrobromide, there was found a hard crust sticking to the bottom of the flask. It was separated, purified by recrystallising in water and converted into its free base as usual. The phenolic base so obtained, after being recrystallised several times from a mixture of chloroform and alcohol, formed prisms, (see fig. 3) melting constantly at 237°C, readily soluble in hot chloroform, but not in other organic solvents in which it was only sparingly soluble. Unlike Corydalis F it was dextro-rotatory; a 0.4 per cent solution in chloroform gave a specific rotation+1.20° in 1 dm tube, (@) 25/D= +300°. It showed the following colour reactions; concentrated sulphuric acid, colourless: Erdmann’s reagent, yellowish orange; Froehde’s reagent, violet, green and then blue. The last colour reaction differentiates Corydalis G from Corydalis F. Its hydrobromide crystallised out from water as prisms (see fig. 4), m.p. 247°C, On account of the small quantity of Corydalis G isolated in a pure state, the molecular formula has not been determined. An intimate mixture of Corydalis F and Corydalis G melted at 214°C.

(4) Corydalis H.

The fraction 4, an alcoholic extract as described in a previous communication (1) was concentrated in vacuo at low temperature. The aqueous residue which contained very little alcohol was first extracted with benzene to remove impurities, (and also some basic substances escaped from previous benzene extractions) and then with chloroform. The chloroform extract, when dried and distilled, left behind a dark resinous residue which was taken up with a little alcohol and allowed to crystallise. After standing in a cool place for several months, no crystals could be isolated. Acidified with hydrobromic acid, well formed prisms were obtained. When crystallised pure from alcohol, it formed yellowish long prisms (see fig, 5),m.p. 235°. It was found to bea hydrobromide and named Corydalis H. It was soluble in water, alcohol and chloroform. Its aqueous solution was optically inactive (a) 20/D=0°. A further quantity of the same hydrobromide was obtained from the above aqueous residue by acidifying with hydrobromic acid and extracting with chloroform. When dissolved in water, made alkaline with