Thiophene, Furans, and Related Aromatic Compounds from Eupatorium heterophyllum

Abstract

A thiophene, two furans, a dihydro furan, and two acetylenic benzene derivatives were isolated from the roots of Eupatorium heterophyllum collected in China. Structures were established on the basis of spectroscopic analyses as well as chemical transformations.

Dihydrobenzofurans and Propynylthiophenes From the Roots of Eupatorium heterophyllum

“…5 However, our results clearly suggested a lower chemical diversity in the roots. 6 The difference in the chemical diversity between the aerial parts and roots may be important for plant physiology and chemical ecology. For example, biosynthesis in the aerial part was most likely sensitive to changes in the environmental conditions, whereas biosynthesis in the roots was generally not affected by environmental factors.…”

“…The separation of the fractions via preparative high-performance liquid chromatography (HPLC) using various types of columns afforded seven new compounds ( 1 – 7 ), an inseparable mixture of diastereomeric isomers of new compounds ( 8 and 9 ), along with 13 known compounds. By comparison of spectroscopic data with data in literatures, the known compounds were identified as six dihydrobenzofurans ( 10 , 7 11 , 8 12 , 9 13 , 6 14 , 10,11 and 15 12 ), two benzofurans ( 16 7,13 and 17 14 ), one enyne-type compound ( 18 6 ), one dihydroxy-formyl-acetophenone ( 19 15 ), and three propynyl thiophenes ( 20 , 16 21 , 16 and 22 6 ) (Figure 1).…”

“…This finding was consistent with a similar previous study. 6 Interestingly, the aerial parts of this plant have been shown to contain mainly sesquiterpenoids and displayed considerable chemical diversity, which was dependent on the collection site. 5 However, our results clearly suggested a lower chemical diversity in the roots.…”

“…5 Additionally, an investigation on the roots (underground part) of E. heterophyllum , which were collected from five districts in China showed only small differences in chemical compositions. 6 In this study, we further examined the roots of E. heterophyllum , which were collected from Sichuan, China. The isolation, determination of structures, and identification of new dihydrobenzofurans and propynylthiophenes were described in this paper.…”

Constituents of Coreopsis lanceolata Flower and Their Dipeptidyl Peptidase IV Inhibitory Effects

“…Additional signals for a methyl group at δ H 2.02 (3H, s, H-14)/δc 4.6 (C-14) and six acetylene carbons at δc 81.3 (C-13), 75.4 (C-8), 74.0 (C-9), 64.6 (C-12), 67.4 (C-11) and 59.0 (C-10) indicated the presence of a 1,3,5-heptatriyne group, which was attached at the trans-olefin group by the 1 H- 13 C HMBC NMR correlations of H-7/C-9 and H-14/C-12. The 1 H NMR and 13 C NMR spectra of 1 also displayed signals for sugar moiety at δc 77.4 (C-5′), 77.3 (C-3′), 74.0 (C-2′), 70.6 (C-4′) and 61.7 (C-6′), including the anomeric signal at δ H 4.00 (1H, d, J = 8.0 Hz, H-1′)/δc 101.3 (C-1′), and the sugar moiety was determined as β -glucopyranoside by the 1 H- 1 H NOESY correlations of H-1′/H-3′ and H-5′, and H-2′/H-4′ [ 25 , 26 ]. In the 1 H- 13 C HMBC NMR spectrum, the hemiacetal proton H-1′ showed a key correlation with C-5, suggesting that the β -glucopyranoside was positioned at C-5 in the polycetylene aglycone.…”