From the sum of extractive compounds obtained by extracting of finely ground, air-dried roots of Ferula cal- carea M.Pimen. two crystalline substance compositions C17H22O3, m.p. 167.0-168.0°C (1) and C₁8H2404 m.p. 84.0-85.0°C have been isolated (2). Based on spectral (IR-, NMR H, 13C, 13C Dept 135) and chemical (alkaline hydrolysis) data it was proved that they had structures identical to the structures of l-chimgin and l- chimganin, respectively.