This form of the alkaloid is more widespread than the d-form, occurring in Corydalis caseana, C. micrantha, C. montana, C. scouleri, C. sibirica and Papaver somniferum. It has [α]26D - 318° (c 0.41, MeOH) or - 289° (c 0.62, MeOH). It forms pale grey needles when crystallized from MeOH. The hydrochloride has m.p. 268-9°C; the picrate, m.p. 206°C (dec.) and the diethyl ether, m.p. 155°C. The oxidation products are the same as for the preceding base.