ABSTRACT
Objective: To study the chemical constituents of the aerial parts of Siegesbeckia pubescens. Methods: A systematic separation of chemical constituents was conducted. Detailed chemical investigation of S. pubescens led to the isolation of six compounds by comprehensive chromatographic Methods: (Extraction, Silic gel C.C, Sephadex LH-20, ODS C. C). The structures of them were fully determined based on spectroscopic analysis including IR, HR-ESI-MS, ESI-MS, 1H-NMR, 13C-NMR, DEPT, HSQC, and HMBC spectrum. Results: A total of six compounds were isolated from the fraction of n-butanol extract of S. pubescens including one new monoterpenoid glycoside named (2Z,5E)-7-hydroxy-3,7-dimethyl-2,5-octadiene-1-O-[α-L-rhamnpyranosyl (1→6)]-β-D-glucopyranoside (1), four known diterpenoid glucosides named pubeside D (2), ent-15,16,19-trihydroxypimar- 8(14)-en-2-one-19-O-β-glucopyranoside (3), ent-15,16-dihydroxypimar-8(14)-en-2-one-19-oic-β-glucopyranoside (4), and neodarutoside (5), and eleutherazine B (6). Conclusion: Compound 1 is a new compound, named as siegeside F, and compound 6 is isolated from this species for the first time.
ABSTRACT
OBJECTIVE: To identify the secondary metabolites of endophytic fungus C. capsici. METHODS: Various column chromatographic methods were used to isolate and purify compounds, such as silica gel, Sephadex LH-20 and semi-prep HPLC. The structures were established on the basis of spectral analysis. RESULTS: Thirteen compounds were isolated and identified as GKK1032(1), altertoxin I(2), ergosta-7, 22-dien-3β, 5α, 6β-triol(3), ergosterol(4), 20-hydroxylergosta-4, 6, 8(14), 22-tetraen-3-one(5), ergosta-7, 22-diene-3, 6-dione(6), isocyathisterol(7), ganodermaside D(8), TCA 3a(9), TCA 3b(10), nicotinamide(11), tyrosol(12) and 4-hydroxybenzaldehyde(13). CONCLUSION: All these compounds are isolated from C. capsici for the first time.
ABSTRACT
Objective: To study the chemical constituents from the aerial parts of Siegesbeckia pubescens. Methods: The compounds were separated and purified by silica gel column chromatography and TLC, and their structures were determined by analyses on the physicochemical properties and spectral data. Results: Three oxylipins were obtained and identified as 3-(myristoyloxy)-2-(isobutyloxy)-4-methylpentanoic acid (1), 3-(myristoyloxy)-2-hydroxy-4-methylpentanoic acid (2), and γ-dodecyl-α-hydroxy-γ-lactone (3) from the ethanol extract of S. pubescens. Conclusion: The two new oxylipins 1 and 2, named siegesbeclipin A and siegesbeclipin B, and known compound 3 is obtained from this plant for the first time.