Structure determination of five trace chemical constituents from roots of Linum usitatissimum

To investigate the trace chemical constituents from the roots of Linum usitatissimum.Isolation and purification of the trace constituents were carried out mainly by solvents extraction and macroporous adsorbing resin and silica gel column chromatography. The structures of the isolates were elucidated by extensive spectroscopic analysis,including 1D and 2D NMR, MS, and HRMS.Five trace compounds were isolated and identified as 3-methyl-2, 5-pyrrolidinedione-5-oxime (1), hypoxanthine (2), nonanedioic acid-1,9 (3), and the mixture of isoleucine and leucine(4 and 5).Compound 1 is a new compound, and compounds 2-5 are isolated from L. usitatissimum for the first time.