A new methoxylated flavone from Lonicera hypoglauca and its chemotaxonomic significance

Phytochemical investigation of the stems and leaves of Lonicera hypoglauca Miq. led to the isolation of one novel methoxylated flavone, acunminatin (7,2′,4′-trihydroxyl-5,5′- methoxyflavone) (1), and fourteen known compounds (2–15), including six flavonoids (mearnsetin 2, kaempferol 3, acacetin 4, 5,7,3′,4′-tetramethoxyflavone 5, tricin 6, and 5,7,3′,4′,5′-pentamethoxyflavone 7), two coumarins (umbelliferone 8 and scopoletin 9), two phenylpropanoids (trans-ferulic acid 10 and chlorogenic acid 11), two iridoid glycosides (loganin 12 and sweroside 13), and two triterpenoids (uvaol 14 and ursolic acid 15). The structures of the compounds were identified by spectroscopic analysis and by comparing their spectral data with those reported in the literature. Five of these compounds (1, 2, 4, 5, and 7) were isolated from the L. genus for the first time, and compounds 6–8 and 14–15 were isolated for the first time from L. hypoglauca. The chemotaxonomic significance of the isolated compounds in the L. genus and the Caprifoliaceae family are discussed herein.     

Chemical constituents from Lagopsis supina (Steph.) Ik.-Gal. ex Knorr

Phytochemical investigation of the whole plants of Lagopsis supina (Steph.) Ik.-Gal. ex Knorr. led to the isolation of 18 compounds (1–18), including ten phenylethanoid glycosides (1–10), one phenylmethanoid glycoside (11), four megastigmane glycosides (12–15), and three monoterpenoid glycosides (16–18). Lagopsides A (1) and B (2) were identified as new phenylethanoid glycosides. This is the first report of compounds 7, 11, 12, 15, and 16 from the Labiatae family, while compounds 4–6, 8–10, 13–14, and 17–18 were isolated from the genus Lagopsis for the first time. The chemotaxonomic significance of these isolated compounds was summarized.     

Chemical constituents from Cistanche sinensis (Orobanchaceae)

Phytochemical investigation of 70% aqueous EtOH extract of Cistanche sinensis led to the isolation of fifteen compounds (1–15), including nine phenylethanoid glycosides (PhGs, 1–9), five iridoid glycosides (10–14), and one lignan glycoside (15). Their structures were determined on the basis of 1D- and 2D-NMR experiments and by comparison with physical data of known compounds. Among the isolated compounds, 1 was identified as a new compound, three compounds (9, 14, and 15) were firstly reported from the genus Cistanche, and seven compounds (2–6, 11, and 12) were isolated from C. sinensis for the first time. PhGs with a 6′-O-rhamnosyl moiety such as cistansinenside B (1), poliumoside (7), and 2′-O-acetylpoliumoside (9) could serve as chemotaxonomic markers to differentiate C. sinensis from other species of Cistanche.     

Chemical constituents from Orobanche cernua Loefling

Phytochemical study of Orobanche cernua Loefling afforded 17 compounds, including eleven phenylpropanoid glycosides (1–11), two flavonoids (12, 13), one lignan (14), and three phenolic acids (15–17) were isolated from the fresh whole plant of O. cernua. Their structures were identified by spectroscopic analyses and by comparison of their spectral data with those reported in the literature. This is the first report of isolation of compounds (6, 8, 9, 11, 14–16) from O. cernua and compounds (14, 15) from the family Orobanchaceae, respectively. Compound 14 was obtained from natural source for the first time, the chemotaxonomic significance of these compounds was summarized.     

Chemical constituents of Chimaphila japonica Miq

A phytochemical study of the whole plants of Chimaphila japonica Miq. led to the isolation of 23 compounds, including ten triterpenoids (1–10), six flavonoids (11–16), two sterols (17 and 18), two quinonoids (19 and 20), one saccharide derivative (21), one phenolic glycoside (22), and one megastigmane glycoside (23). The structures of these isolated compounds were identified using NMR spectroscopy (¹H and ¹³C) by comparison with previously reported data. All compounds, except 19 and 22, were reported from C. japonica for the first time. Among them, 16 compounds (1–4, 6–9, 12, 13, 15, 16, 18, 20, 21, and 23) were reported from genus Chimaphila for the first time, while compounds 12, 16, and 23 were isolated from the Ericaceae family for the first time. The chemotaxonomic significance of the isolates was also discussed.     

Chemical constituents of the root bark of Ulmus davidiana var. japonica and their potential biological activities

The root bark of Ulmus davidiana var. japonica (Ulmaceae), commonly known as yugeunpi, has been used as a traditional Korean medicine for the treatment of gastroenteric and inflammatory disorders. As part of continuing projects to discover bioactive natural products from traditional medicinal plants with pharmacological potential, phytochemical investigation of the root bark of this plant was carried out. This led to the successful isolation of a new chromane derivative (1) and 22 known compounds: catechin derivatives (2–5), megastigmane glycoside (6), dihydrochalcone glycosides (7 and 8), flavanone glycosides (9 and 10), coumarins (11 and 12), lignan derivatives (13–17), and phenolic compounds (18–23). The structure of the new compound (1) was determined with 1D and 2D NMR spectroscopy and HR-ESIMS, and its absolute configurations were achieved by chemical reactions and the gauge-including atomic orbital (GIAO) NMR chemical shifts calculations. All the isolated compounds were evaluated for their potential biological activities including neuro-protective, anti-neuroinflammatory, and anti-Helicobacter pylori activities. Among the isolates, compounds 1, 8, and 20 displayed stronger potency by causing a greater increase in the production and the activity of nerve growth factor (NGF) in C6 glioma cells (147.04 ± 4.87, 206.27 ± 6.70, and 143.70 ± 0.88%, respectively), whereas compounds 11, 14, and 19 inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated murine microglial cells (IC₅₀ of 18.72, 12.31, and, 21.40 µM, respectively). In addition, compounds 1, 11, 18, and 20 showed anti-H. pylori activity with MIC values of 25 or 50 µM against two strains of H. pylori 51 and 43504. These findings provide scientific evidence that supports the traditional usage of U. davidiana var. japonica root bark in the treatment of gastroenteric and inflammatory disorders.     

Chemotaxonomic significance of lignans from Serissa japonica (Thunb.) Thunb

Sixteen known lignans were isolated from the 95% alcohol extract of the whole plant of Serissa japonica (Thunb.) Thunb., including nine furofurans (1–9), three tetrahydrofurans (10–12) and four arylnaphthalenes (13–16). In the present report, compounds (+)-epipinoresinol (1), (+)-1-hydroxy-6-epipinoresinol 4,4″-di-O-methyl ether (3), (−)-pinoresinol (4), (+)-8-hydroxypinoresinol (6), pseuderesinol (7), (+)-1-hydroxysyringaresinol (8), (−)-(7′S,8S,8′R)-4,4′-dihydroxy-3,3′,5,5′-tetramethoxy-7′,9-epoxylignan-9′-ol-7-one (10), wikstrone (11), 7'-(+)-oxomatairesinol (12), (+)-cycloolivil (13), (+)-isolariciresinol (14), 5-methoxy-(+)-isolariciresinol (15) and cyclolignans (16) were reported from the Serissa genus for the first time, and compounds (+)-lirioresinol A (2) and (−)-lirioresinol B (5) were firstly isolated from the plant. Their structures were elucidated on the basis of extensive spectroscopic and chemical analyses. Moreover, the chemotaxonomic significance of the isolated compounds is discussed.     

Phenylpropanoids and some nitrogen-containing constituents from the roots of Isatis indigotica Fort. (Cruciferae)

The present phytochemical investigations of Isatis indigotica Fort. resulted in the isolation of seven lignans (1–7), three aromatic glycosides (8–10), three nucleosides (11–13) and two bis-indole alkaloids (14–15). Among them, compounds 5, 6 and 9 were obtained from this genus for the first time. The chemotaxonomic importance of these compounds was also summarized.     

Chemical constituents isolated from the roots of Sanguisorba officinalis L. and their chemotaxonomic significance

Phytochemical investigation of the roots of Sanguisorba officinalis L. led to the isolation of thirty-eight compounds, including seventeen triterpenoids (1–17), six monoterpenoid glycosides (18–23), six flavonoids (24–29), six phenols (30–35), two glycosides (36–37), and one lignan (38). The chemical structures of these compounds were elucidated on the basis of spectral data and by comparisons of spectroscopic data with reported values in the literature. Compounds 18, 29, and 36–37 were the first to be reported in the family Rosaceae, compounds 10, 12, 15, 27–28, and 38 were firstly identified from the genus Sanguisorba, and compound 11 was obtained from S. officinalis for the first time. The chemotaxonomic significance of these isolated compounds has also been discussed.     

New hexalactone derivatives and a pair of new oxaspiro-carbon epimeric glycosides from the fruits of Illicium lanceolatum

Five new compounds (1–5), including three hexalactone derivatives (1–3) and a pair of new oxaspiro-carbon epimeric glycosides (4 and 5), and six known compounds (6–11) were obtained from the fruits of Illicium lanceolatum. The structures of the new compounds were elucidated using extensive spectroscopic data. The absolute configurations of compounds 1–3 were determined by an analysis of their CD spectra. It was determined that compounds 4 and 5, which are epimeric at C-5, possess the same 1-oxaspiro[4,5]decane-7α,8α,9β-triol moiety. Plausible biogenetic pathways for 4 and 5 derived from the key precursor shikimic acid were proposed. Compounds 1–11 were all assayed on monosodium glutamate-induced human neuroblastoma SH-SY5Y cell damage. The results demonstrated that compounds 4, 5, and 8–10 possess potential neuroprotective effects. The anti-inflammatory, antiviral, and cytotoxic activities of 1–11 were also evaluated.     

Chemical constituents from Bupleurum chinese and their chemotaxonomic significance

A phytochemical investigation of the roots of Bupleurum chinese DC. led to the isolation of eighteen compounds, including three chromones (1–3), seven flavonoids (4–10), one dihydrochalcone (11), two phenylpropanoid glycosides (12–13), one lignan (14), three sterols (15–17) and one stilbenoid (18). Their structures were elucidated on the basis of NMR spectroscopic analysis and comparison with literature data. Compounds 6–7, 11–14 and 18 were firstly reported from the genus Bupleurum and the family Apiaceae. Moreover, the chemotaxonomic value of the isolates was also discussed.     

Chemical constituents of Peperomia tetraphylla (Forst. F.) Hooker et Arnott

Sixteen compounds were isolated from the whole herbs of Peperomia tetraphylla (Forst. F.) Hooker et Arnott by phytochemical methods, including eight flavonoids (1–3, 6, 7, 14–16), three lignans (8–10), three beta sitosterols (4, 5, 11), and two phenolic acids (12, 13). Their structures were identified by the analysis of NMR and MS, as well as the comparisons to the reported data. Among them, 2″-O-xylosylisoswertisin (14) was firstly isolated from the Piperaceae family, as well as ten compounds (1–4, 7, 10–11, 13, 15–16) were isolated from P. tytraphylla for the first time. Moreover, the chemotaxonomic significance of constituents isolated from P. tytraphylla was also discussed.     

Chemical constituents of Leucas zeylanica and their chemotaxonomic significance

Chemical study of the whole plant of Leucas zeylanica (L.) B. Br. has led to isolation of a new norditerpenoid isomer (1), along with 29 known compounds, including one norditerpenoid (2), three flavonoid glycosides (3–5), six flavonoids (6–11), two phytosterols (12–13), two phenylpropanoids (14, 19), two phthalate esters (15, 16), two phenolic compounds (17, 18), five terpenoids (20–24), one aliphatic glycoside (25), one nucleobase (26), one amino acid (27), two alkaloids (28–29), and one cytochalasin (30). The structures of these compounds were identified using NMR spectroscopic methods and comparing them with those previously reported. Twelve compounds (6, 15, 17–20, 22, 23, 26–29) were isolated for the first time from Leucas zeylanica and ten others (2, 4, 5, 7, 14, 16, 21, 24, 25, 30) from the Leucas genus. This study also discusses the chemotaxonomic relationships between Leucas zeylanica and other species of Leucas.     

Chemical constituents from Hovenia dulcis Thunb. And their chemotaxonomic significance

Phytochemical investigations on the fruit stalks and seeds of the plant Hovenia dulcis Thunb. led to the isolation of twenty-one compounds, including three triterpenes (1–3), two sterols (4–5), five flavonoids (6–10), two sesquiterpenes (11–12), one lignan (13), two phenylpropanoids (14–15), four benzoic acid derivatives (16–19), one acid amide (20) and one cerebroside (21). The structures of these compounds were elucidated on the basis of spectroscopic analysis and comparison with previous literatures. Among them, ten compounds (4, 11–12, 14–20) were isolated from familiy Rhamnaceae, two (13, 21) from the genus Hovenia, and three (5, 8, 10) from the species Hovenia dulcis Thunb. for the first time, respectively. The chemotaxonomic significance of these isolates was also discussed.     

Chemical constituents from Schefflera leucantha R.Vig. (Araliaceae)

Processive phytochemistry and pharmacological investigation of Schefflera leucantha R.Vig. (Araliaceae) led to the isolation of fifteen known compounds: a nucleobase (1), six small aromatic molecules (2–7), three phenylpropanoids (8–10), four lignans (11–14) and a fatty acid derivative (15). Spectroscopic methods were used to establish the structure and configuration of isolates, followed by their unambiguous confirmation with literature data. We report for the first time (to the best of our knowledge), the isolation of β-amino-3-methoxy-4-hydroxybenzene-ethanol (4) from a natural source. Furthermore, compounds 1, 5, 9–15 are being reported from Araliaceae family for the first time, whereas compounds 2, 3, 6–8 from the genus Schefflera for the first time. The biological screening results show that compounds 9 and 10 induce a moderate inhibitory effect on aldose reductase, while compounds 3, 5, and 8 display significantly high neuroprotective activities.     

Chemical constituents isolated from the roots and rhizomes of Smilacina japonica

Phytochemical investigation of the roots and rhizomes of Smilacina japonica A. Gray led to the isolation of 16 compounds, including six steroidal saponins (1-6), one amide (7), one fatty alcohol (8), one steroidal sapogenin (9), two flavones (10-11), one glycoside (12), one phenol (13), one aliphatic acid (14), and two sterols (15-16). All of these compounds were isolated for the first time from the roots and rhizomes of S. japonica while compounds 1-13 were identified for the first time from the genus Smilacina, of which compounds 9, 11, and 13 were isolated from the Liliaceae family for the first time. Furthermore, the isolation of compound 9 was reported for the first time in plants. Their structures were identified by spectroscopic methods and compared previously published data. The chemotaxonomic significance of these isolated compounds has also been discussed.     

Chemical constituents from the aerial parts of Ajania fruticulosa

The isolation and identification of sixteen compounds extracted from the aerial parts of A. fruticulosa have been reported in the present study, including eight flavonoids (1, 2, 3, 4, 5, 6, 7 and 8), three terpenoids (9, 10 and 11), two sterols (12 and 13), one lignan (14), one fatty acid (15) and one fatty acid ethyl ester (16), wherein six compounds (2, 3, 4, 5, 10 and 14) have been isolated from A. fruticulosa for the first time. Furthermore, among the identified compounds, three compounds (6, 7 and 11) have also been reported for the first time in the genus Ajanin and three compounds (8, 15 and 16) have not been isolated and reported from other plants of the family Asteraceae. In addition, the chemotaxonomic significance of these compounds was discussed.     

Four new glycosides from the seeds of Cassia obtusifolia

Four new glycosides, including one anthraquinone glycoside (1), one naphthalene glycoside (2), and two naphthopyrone glycosides (3–4), with 10 known compounds (5–14) were isolated from the seeds of Cassia obtusifolia L. The new structures were determined by spectroscopic analysis and chemical transformations.     

Chemical constituents with ɑ,β-unsaturated carbonyl group from the whole plants of Erigeron breviscapus (Vant.) Hand.-Mazz. (Asteraceae)

Phytochemical characterization of the whole plants of Erigeron breviscapus (Vant.) Hand.-Mazz. Led to the isolation of two indole derivatives (1–2), seven monoterpenoids (3–9), two sesquiterpenoids (10–11), and four pyrone derivatives (12–15). The structures of these compounds were examined with spectroscopic methods, and also by comparing with previously reported spectroscopic data. Among them, ten compounds (1–2, 6–11, 14–15) are reported from Erigeron breviscapus for the first time. In addition, three compounds (2, 8–9) are isolated for the first time from Asteraceae family. On the basis of chemical research, we also described the chemotaxonomic significance of these compounds.     

Chemical constituents from Valeriana officinalis L. var. Iatifolia Miq. and their chemotaxonomic significance

Twenty-one compounds, including four monoterpenoids (1–4) (two new natural products, 1 and 2), four sesquiterpenes (5–8), two iridoids (9 and 10), four steroids (11–14), five phenolic compounds (15–19), and two alkaloids (20 and 21), were isolated from the roots of Valeriana officinalis L. var. Iatifolia Miq. Their chemical structures were established by spectroscopic methods and further confirmed by comparison with published data in the literature. Among them, eight compounds (1, 2, 6–8, 13, 18, and 21) are being reported from the family Valerianaceae for the first time, and compounds 9–12 were obtained from V. officinalis for the first time. The chemotaxonomic significance of the isolated compounds is discussed.