Studies on the Constituents from the Aerial Part of Baccharis dracunculifolia DC. II.

Abstract

In the course of our research on the constituents of Brazilian plants, we started investigation of the glycosides from Baccharis dracunculifolia DC. (Compositae); we previously reported the structures of dracunculifosides A-J from the aerial part of this plant.1) Recently, ten new glycosides were isolated along with five known compounds identified by their NMR spectral data [1: 3,4-O-dicaffeoylquinic acid methyl ester, 2) 2:]. This paper also describes the isolation and structural elucidation of these new compounds.The extraction of the constituents from B. dracunculifolia DC. was described in a previous paper.1) The adsorbed material on the Mitsubishi Diaion HP-20 column was eluted with 50% MeOH in water, 70% MeOH in water and MeOH, continuously. The residues of the 50% and 70% MeOH eluates gave compounds 1-15.Compound 4 was suggested to have the molecular formula, C 35 (d 149.7, 147.0, 127.8, 123.0, 116.7, 115.3) and six carbon signals due to the sugar moiety (d 102.6, 77.9, 75.6, 74.9, 72.2, 64.7) along with the signal due to the aglycone moiety. Thus, compound 4 was believed to consist of an aglycone, one monosaccharide and an (E)-caffeoyl group.Concerning the aglycone moiety, the 13 C-NMR spectrum showed twenty carbon signals including twelve aromatic carbon signals and the methoxyl carbon signals, and in the 1 H-NMR spectrum, the AMX type- [d 7.05 (1H, d, Jϭ8. Mild alkaline hydrolysis of compound 4 afforded 4a which was identified as pinoresinol O-b-D-glucopyranoside (2) 3,6) by the HPLC analysis and The molecular formulae of dracunculifosides K (5) and L (6) were expected to be C 25 H 28 O 11 and C 28 H 30 O 13 by the HR-FAB-MS. The 1 H-and 13 C-NMR spectra of 5 and 6 displayed the signals due to glucopyranose and an (E)-caffeoyl group in addition to the signal due to each aglycone. The similarity of the 13 C-NMR spectral data of 5 to those of myzodendrone 7) and dracunculifoside I 1) let us to guess that the aglycone of 5 was 4-(3,4-dihydroxyphenyl)-butan-2-one. Similarly, comparison of the 1 H-and 13 C-NMR spectral data of 6 with those of dracunculifoside J 1) indicated the presence of dracunculifoside J and the (E)-caffeoyl group in 6. Production of myzodendrone and (E)-caffeic acid from 5, and dracunculifoside J and (E)-caffeic acid from 6 by mild alkaline hydrolysis confirmed the above presumption. Consistency of the 1 H-and 13 C-NMR spectral data of the sugar and ester moieties in 5 and 6 with those in 4 suggested that the (E)-caffeoyl group was attached to the C-6 position of b-D-glucopyranose. Accordingly, the structures of dracunculifosides K (5) and L (6) were determined as shown in Chart 1.Dracunculifoside M (7) had the molecular formula, . The 1 H-and 13 C-NMR spectra of 7 also showed the signals due to glucopyranose and an (E)-caffeoyl group. The J value of the anomeric proton signal of glucopyranose (Jϭ8.0 Hz) and GC analysis after acid hydrolysis indicated that this glucopyranose had a b-D-configuration. With regard to the aglycone moiety, fifteen carbon signals were observed in the 1...

Inhibitory Activity against Tobacco Mosaic Virus (TMV) Replication of Pinoresinol and Syringaresinol Lignans and Their Glycosides from the Root of Rhus javanica var. roxburghiana

“…The 13 C and 1 H NMR spectra showed the presence of a β-glucopyranosyl moiety, two feruloyl moieties, two 1,3,4,5-tetrasubstituted symmetrical benzene signals (δ 6.67, 2H), two oxygenated methylene signals at δ 4.20 (2H, dd, J ) 9.4, 3.4 Hz), 3.84 (2H, overlapping), and four methine signals including two oxygen-bearing methines [δ 4.66 (2H, d, J ) 3.4 Hz, H-7,-7′), 2.99 (2H, m, H-8,-8′)], along with six methoxy signals at δ 3.81 (6H, s) and 3.80 (6H, s) (see Table 1). By comparison of the above 1 H NMR data with those of syringaresinol-O-β-glucopyranoside (15), compound 4 was determined to be a derivative of syringaresinol-O-β-glucopyranoside with two additional feruloyl moieties. Mild alkaline hydrolysis of compound 4 produced {[R] D 27 ) -26.3 (c ) 0.24, MeOH)}, which was identified as syringaresinol-O-β-D-glucopyranoside.…”

Anti-leishmanial effects of purified compounds from aerial parts of Baccharis uncinella C. DC. (Asteraceae)

“…After partition procedures and TLC, NMR, and HPLC analyses of obtained organic phases, the presence of non-glycosylated flavonoid and triterpenes in the CH 2 Cl 2 phase and phenolic derivatives in the EtOAc phase was suggested. These phases were subjected to several chromatographic steps and NMR spectroscopic analysis to afford a mixture of oleanolic+ursolic acids (Seebacher et al 2003) and pure pectolinaringenin (Hase et al 1995) from CH 2 Cl 2 phase as well as pure caffeic and ferulic acids (Nagatani et al 2002) from EtOAc phase.…”

Biotoxicological Analyses of Trimeroside from Baccharis trimera Using a Battery of In Vitro Test Systems

“…There are few studies showing the occurrence of compounds of this class in Asteraceae species, such as the work from Gao et al [40], Ragasa et al [41], and Nagatani et al [42], which have reported monoterpene glycosides from Hymenoxys ivesiana , Erigeron linifolius , and B. dracunculifolia . In the literature, some studies have described the presence of 2-hydroxy-isoforone in plants but never as a nor-monoterpene glycoside; this unusual class of compound has been previously reported only twice (ranthenone glucoside and officinoterpenoside D) [33, 34].…”