Chinese Journal of Physiology

ALKALOIDS OF CORYDALIS 71

in aqueous solution. When crystallised pure, the hydrobromide was worked up for Corydalis F by dissolving in water, making alkaline with potassium carbonate and extracting with chloroform. The crude Corydalis F so obtained was further purified by repeatedly recrystallising from chloroform with the addition of alochol until a constant melting point was obtained. Corydalis F forms colourless rhomboid crystals (see fig. 1) m.p. 237°C. It was sparingly soluble in organic solvents except chloroform, in which it was easily soluble on warming. Its chloroform solution and also its crystals became coloured on keeping. It dissolved in a dilute solution of caustic alkali forming a colourless solution, A 0.4 per cent solution in chloroform gave a specific rotation -1°, in 1 dm tube, (@) 25/D = -250°. Its molecular formula

has been found to be C.,H5,0 N or Cy9H»,0,N according to the following analysis: —

(i) 0.1180 gm substance gave 0.8036 gm CO, and 0.0757 gm H2O, C=7016; B72: (ii) 0.1180 gm substance gave 0.3034 gm CO, and 0.07385 gm HO. C=7).12; H=6:92. (iii) 0.1194 gm substance gave 4.40 cc moist nitrogen at 25°C and 755 mm pressure, N=4.06. Calculated for the formula C.H04N or CoH»,O, N C=7)).38 C=70.17 H =6.74 = 700 H =4.10 N =4.09

This substance may therefore have one of the above two formulae.

It showed the following colour reactions; concentrated sulphuric acid, colourless; Erdnrann’s reagent, yellowish orange; l'roehde’s reagent, violet and then blue. Its hydrobromide and hydrochloride were prepared.

(a) Hydrobromide. Prepared by dissolving pure Corydalis I’ in a slight excess of hot dilute hydrobromic acid, It separated out as a jelly at first, but was crystallised by warming the liquid. It formed prismatic

needles (see fig. 2), melting at 222°C to a reddish liquid. It was soluble in water and alcohol.

(b) Hydrochloride. Obtained by dissolving Corydalis F in an excess of dilute hydrochloric acid. In pure water and alcohol, it was very soluble. It formed fine needles and contained some water of crystallisa-