Two new lignans from Gymnotheca involucrata / 中草药

Objective: To study the chemical constituents from Gymnotheca involucrata. Methods: The chemical constituents of G. involucrata were isolated by different column chromatographic techniques. The structures of these compounds were identified by comprehensive analysis of the spectroscopic data. Results: Six compounds were isolated from G. involucrata. The compounds were identified as gymnothelignan Y3 (1), gymnothelignan Y4 (2), gymnothelignan T (3), gymnothelignan N (4), gymnothelignan O (5), and gymnothelignan M (6). Conclusion: All the compounds are isolated from G. involucrata for the first time, and compounds 1 and 2 are two new compounds.