The genus Magnolia includes about 700 species. Plants of this genus are mainly found in North America and South-East Asia. The alkaloids of Magnolia soulangeana introduced into the Botanical Garden of the Academy of Sciences of the Republic of Uzbekistan have been investigated previously, with liriodenine, remerine, and oxolaureline isolated. Continuing the study of alkaloids of plants of the genus Magnolia, we investigated Magnolia kobus gathered in the vegetation period in June 1991. By usual chloroform extraction, we obtained 0.31% total alkaloids from leaves and 0.12% from stems. The mixture of bases from the leaves was divided into phenolic and nonphenolic fractions, and the alkaloids were separated chromatographically on a silica gel column. From the nonphenolic fraction, remerine and liriodenine were isolated; from the phenolic fraction, asimilobine and a substance with the composition C22H26O8 (mp 168-170°C decomp.) were obtained. The latter substance was identified as the lignan syringaresinol (previously isolated from Liriodendron tulipifera L.) via analysis of its UV, mass, and PMR spectra and comparison with literature. Liriodenine was isolated from the stems.