Chemical constituents from the stem and root bark of Daphne giraldii Nitsche (Thymelaeaceae)

Eighteen compounds were isolated from the stem and root bark of Daphne giraldii Nitsche, including three categories: flavans (1–6), diphenylpropanes (7–12), and lignans (13–18). This is the first report on the occurrence of compounds 9, 11, 13–15, and 17–18 in D. giraldii. These compounds were elucidated using spectroscopic methods and by comparing their data to those reported in the literature. On the basis of our previous chemical research, the chemotaxonomic significance of the isolated compounds was discussed to a greater degree.     

Chemical constituents from Piper boehmeriifolium (Miq.) Wall. ex C. DC

The chemical investigation of whole plants Piper boehmeriifolium (Miq.) Wall. ex C. DC. led to the isolation of 22 compounds, including two lignans (1–2), sixteen amide alkaloids (3–18), one diterpene (19), two monoterpenes (20–21), and one phenylpropanoid (22). Their structures were elucidated by extensive spectroscopic analyses including NMR, MS, and by comparison with the literature. Compounds 1–2, 6–7, 11–12, 14, and 17–22 were firstly isolated from P. boehmeriifolium, while compounds 2, and 19–20 were isolated from Piper genus for the first time. The chemotaxonomic significance of these isolated compounds is discussed.     

Alkaloids and monoterpenes from the leaves of Isatis tinctoria Linnaeus and their chemotaxonomic significance

Phytochemical investigation of the leaves of Isatis tinctoria Linnaeus led to the isolation of thirty compounds, including thirteen indole alkaloids (1–13), seven quinazolinone alkaloids (14–20), two quinoline alkaloids (21–22), one quindoline alkaloid (23), one simple amide alkaloid (24) and six monoterpenes (25–30). According to spectroscopic data analysis and comparison with the previously reported literature, their structures were elucidated. Among them, six compounds (12, 13, 17, and 22–24) have not been reported from the family Brassicaceae and eight compounds (3, 7, and 25–30) were isolated from the genus Isatis for the first time. Furthermore, the chemotaxonomic significance of isolated compounds has also been elaborated.     

Phytochemical and chemotaxonomic studies on Dioscorea collettii

A chemical investigation of Dioscorea collettii led to the isolation of twenty-nine compounds, including six steroid saponins (1–6), thirteen monocyclic phenols (7–19), two flavonoids (20–21), three sterols (22–24), and five cyclodipeptides (25–29). The chemical structures of these compounds were elucidated using spectroscopic methods and by comparing their data to that reported in the literature. This study is the first report of compounds 2–4, 7, 14–17, 21, and 23–24 in D. collettii, while compounds 8–13, 18–20, and 25–29 were first isolated from the genus Dioscorea and the family Dioscoreaceae. The chemotaxonomic significance of the isolated compounds is discussed.     

Chemical constituents of the Piper crocatum leaves and their chemotaxonomic significance

Chemical study of Piper crocatum leaves has led to isolation of a new megastigmane glucoside isomer (18), along with 23 known compounds including fifteen phenolic compounds (1–15), two monoterpenes (16 and 17), three sesquiterpenes (19–21), a phenolic amide glycoside (22), a neolignan (23), and a flavonoid C-glycoside (24). Structures of these compounds were identified via spectroscopic methods and compared with those reported in the literature. Seven compounds (7, 11, 13, 14, 17, 20, and 24) from the P. crocatum species and 17 others (1–6, 8–10, 12, 15–16, 18–19, and 21–23) from the Piper genus and Piperaceae family were isolated and reported for the first time. Furthermore, this study discusses chemotaxonomic relations between P. crocatum and other Piper species.     

Chemical constituents from the heartwood of Toxicodendron vernicifluum (Stokes) F.A. Barkley

A phytochemical investigation of the heartwood of Toxicodendron vernicifluum (Stokes) F.A. Barkley led to the isolation of twenty-five compounds, including sixteen flavonoids (1–15), one flavonolignan (16), one chromone (17), four benzoic acid derivatives (18–21), two triterpenes (22–23) and two sterols (24–25). The structures of these compounds were elucidated on the basis of spectroscopic analysis and comparison with previous literature data. Among them, 8 and 21were isolated from the genus Toxicodendron and 5, 9, 13, 17–20, 22 from the family Anacardiaceae for the first time. Furthermore, 21 had been identified only by LC/MS before. 20 was a synthetic product used as anthelmintics, newly identified as a natural product. Furthermore, the chemotaxonomic value of these isolates was also discussed in detail.     

Chemical constituents from Ilex urceolatus

Twenty-four compounds were obtained from the extract of the leaves of I. urceolatus, which were divided into saturated fatty alcohols (1 and 2), triterpenoids (3–8 and 14–16), lignanoids (9, 20 and 22), coumarins (10 and 19), flavonoids (11–13, 21, 23 and 24) and others (17 and 18). Among them, compounds 1, 2, 17 and 18 were firstly obtained from the genus Ilex, others were isolated from this species for the first time. The chemotaxonomic relationships between I. urceolatus and other species of genus Ilex were also discussed. As a result, the isolated compounds closely matched the ones obtained in other species of the genus.     

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 from the fruits of Vitex trifolia L. (Verbenaceae) and their chemotaxonomic significance

One new labdane-type diterpenoid (1) named viterotulin D, along with twenty-three known compounds, including fourteen diterpenoids (2–15), one monoterpenoid (16), three steroids (17–19), one flavonoid (20), and four phenols (21–24) were isolated from the fruits of Vitex trifolia L. The structures of these compounds were identified based on spectroscopic data interpretation and comparison with previously reported values in the literature. This is the first report on the isolation of compounds (1, 6, 14, 15, 17, and 22) and (2, 9, and 10) from the family Verbenaceae and Vitex trifolia, respectively. The chemotaxonomic significant of the isolates was also discussed.     

Chemical constituents from Euphorbia hirta

Thirty-one compounds, including fourteen triterpenoids (1–14), seven coumarins (15–21), four lignans (22–25), and six diterpenes (26–31) were isolated from the aerial part of Euphorbia hirta. The structures were elucidated by spectroscopic methods and by comparison of their reported spectroscopic data. These compounds have shown the chemical relationships between this plant and other species from the genus Euphorbia.     

Chemical constituents from Cynanchum paniculatum (Bunge) Kitag

Twenty-nine compounds, including five acetophenone derivatives (1–5), three phenanthroindolizidine alkaloids (12–14), seven pentacyclic triterpenoids (15–21) and five C₂₁ steroidal sapogenins (22–26), were isolated from the root of Cynanchum paniculatum (Bunge) Kitag. Their structures were determined by spectroscopic methods and comparison with reported data. Moreover, the chemotaxonomic relationships were also discussed. As a result, acetophenone derivatives, pentacyclic triterpenoids and C₂₁ pregnane sapogenins can be recognized as chemotaxonomic markers for Cynanchum genus, and C. paniculatum has close relationships with some species of genus Cynanchum.     

Chemical constituents of the roots of Scorzonera divaricata and their chemotaxonomic significance

The phytochemical study of the roots of Scorzonera divaricata Turcz led to the isolation of 27 compounds, including eight sterols (1–8), one lignan (9), two cumarins (10, 11), five phenylpropanoids (12–16), six benzene derivatives (17–22), methyl-β-D-fructofuranoside (23), monolinolein (24), and three aliphatic acids (25–27). The structures of isolated compounds were identified using NMR and ESI-MS spectroscopic methods and comparing them with those previously reported. Except for β-daucosterol (8), scopoletin (10) and caffeic acid (16) from S. divaricata, this is the first report of the other 24 compounds from S. divaricata. Among them, eleven compounds (2–6, 11, 17, 19, 20, 23, 25) were reported from genus Scorzonera for first time, suggesting that they could be used to distinguish S. divaricata from the other species of Scorzonera. Furthermore, the chemotaxonomic significance of isolated compounds from S. divaricata has also been discussed.     

Chemical constituents isolated from Valeriana officinalis L

Phytochemical investigations on the leaves of Valeriana officinalis L. led to the isolation of 18 compounds, including eight lignans (1–8), three sesquiterpenoids (9–11), five iridoids (12–16), and two aldehydes (17–18) The structure elucidation of isolated compounds was achieved on the basis of NMR and mass spectral data. Among them, three compounds (9–16, 18) are reported from V. officinalis for the first time and one compound (5) was isolated from the genus Valeriana for the first time. In addition, six compounds (2, 4, 6–8, 17) are isolated for the first time from Valerianaceae family. The chemotaxonomic significance of these isolated compounds has also been 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 Melodinus cochinchinensis (Lour.) Merr. and their chemotaxonomic significance

A phytochemical investigation on the twigs and leaves of Melodinus cochinchinensis (Lour.) Merr. resulted in the isolation and identification of 22 compounds, including seven sesamin-type lignans (1–7), three pentacyclic triterpenes (8–10), one anthraquinone (11), one flavanone (12), two phenolic compounds (13 and 14), five aspidosperma-type indole alkaloids (15–19), and three eburnan-type indole alkaloids (20–22). The structures of these compounds were elucidated by means of spectroscopic analysis, including HREIMS together with 1D and 2D NMR experiments, and comparison with reported data. Among them, compounds 1/4, 2/5, and 3/6 are three pairs epimers at C-7''. Compounds 1–6, 8 and 11 were firstly isolated from the family Apocynaceae, whereas 17 was isolated from Melodinus species for the first time. Compound 8 was only found in Juglans hopeiensis, while 11 was only found in roots of Rubia cordifolia. Compounds 1–6, 8, 11 and 15–22 could be considered as chemotaxonomic markers for M. cochinchinensis. Furthermore, the chemotaxonomic significance and distribution of these isolates in Melodinus genus are discussed in detail.     

Estrogenic activity of constituents from the rhizomes of Rheum undulatum Linné

Stilbenes have been reported to be phytoestrogen compounds owing to its structural similarity to the estrogenic agent diethylstilbestrol. To find new stilbene-derivative phytoestrogens, isolation of stilbene-rich R. undulatum was performed and led to identify six new compounds (1–5 and 28), one newly determined absolute configurations compound (27) together with 21 previously reported compounds (6–26). The structures of compounds were determined on the basis of extensive spectroscopic methods including 1D and 2D NMR and CD spectra data. All the isolated compounds were tested for their estrogenic activities in HepG2 cells transiently transfected with ERα, ERβ and ERE-reporter plasmid. Among them, stilbene-derivatives, piceatannol 3′-O-β-d-xylopyranoside (12), cis-rhaponticin (16) and rhapontigenin 3′-O-β-d-glucopyranoside (17), showed the more potent binding affinity for estrogen receptors than 17β-estrodiol.     

Phytochemical and chemotaxonomic study of Pulsatilla cernua (Thunb.) Bercht. ex J. Presl

Twenty-two compounds were isolated from the 70% EtOH–H₂O extract of Pulsatilla cernua (Thunb.) Bercht. ex J. Presl roots, and their structures were determined based on ¹H NMR, ¹³C NMR and MS spectroscopic data, including (+)-pinoresinol (1), matairesinol (2), 4-ethoxycinnamic acid (3), p-hydroxy ethyl cinnamate (4), 3-(4′-methoxyphenyl)-2(E)-propenoic acid (5), methyl 4-hydroxycinnamate (6), radicol (7), cryptomeridiol (8), fraxinellone (9), diolmycin B2 (10), hederagonic acid (11), hederagenin (12), oleanolic acid (13), 3-O-α-L-arabinopyranosyl-oleanolic acid (14), hederagenin 3-O-α-L-arabinopyranoside (15), 3-O-[α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl] oleanolic acid (16), hederasaponin B (17), kizutasaponin K₁₂ (18), patrinia saponin H3 (19), hederacholichiside F (20), cernuoside A (21) and cernuoside B (22). Eight compounds (3–10) were isolated and identified from the genus Pulsatilla for the first time.     

Chemical constituents from the leaves of Ilex urceolatus

Eighteen compounds, including four hemiterpene glycosides (1–4), three triterpenoid saponins (5–7), four triterpenes (8–11), five sterols (12-16) and two monoterpene glucosides (17 and 18), were isolated from the leaves of Ilex urceolatus C. B. Shang, K. S. Tang et D. Q. Du, which was identified as a new species belonging to the genus Ilex. Among them, compounds 14–18 were firstly isolated from the genus Ilex, others were obtained from I. urceolatus for the first time. This work represented the initially phytochemical study on this plant. The isolated compounds have significant chemotaxonomic characteristics with the other species from this genus.     

Chemical constituents isolated from Clusia criuva subsp. Criuva and their chemophenetics significance

Clusia criuva belongs to the Clusiaceae family and it is endemic to the rupestrian fields in Chapada Diamantina National Park (Brazil). Phytochemical investigation of C. criuva trunks led to the isolation of five triterpenoids [winchic acid (1), betulinic acid (2), lupeol (3), friedelin (4), and friedelinol (5)], four steroids [lanosterol (6), stigmasterol (7), β-sitosterol (8), and sitostenone (9)], seven polyprenylated benzophenone derivatives [propolone A (10), propolone B (11), propolone C (12), propolone D (13), sampsonione B (14), hyperisampsin E (15), and hyperisampsin F (16)], four xanthones [neriifolone C (17), 6-deoxyisojacareubin (18), osajaxanthone F (19), and brasilixanthone B (20)], two biphenyls [aucuparina (21) and 2,2-dimethyl-5-hydroxy-7-phenylchromene (22)], and two tocotrienol derivatives [2Z- and 2E-δ-tocotrienoloic acids (23 and 24)]. Compounds 1, 11, 12, 15, and 16 were isolated for the first time in the Clusiaceae family, compounds 17, 19 and 21 were isolated for the first time in the genus Clusia, whereas 2–10, 13, 14, 18, 20, 22–24 were isolated for the first time in Clusia criuva. Compounds 1, 2, 11, 12, 13 and 15 showed potent in vitro cytotoxic activity against GL-15 glioblastoma-derived human cell line. Chemophenetics significance of these compounds is described herein.     

Chemical constituents from the fruits of Rhus typhina L. and their chemotaxonomic significance

This work describes the isolation and characterization of twenty-nine compounds from the fruits of Rhus typhina L., including eleven flavonoids (1–11), eleven phenols (12–22), two pentacyclic triterpenes (23–24), two organic acids (25–26), one lumichrome (27), one courmarin (28) and one pyrimidine (29) on the basis of their spectroscopic data. Compounds apigenin (1), daidzein (4), orobol (5), 3′, 5, 5′, 7-tetrahydroxyflavanone (6), naringenin (7), butein (8), (-)-catechin (9), quercetin-3-O-α-L-(3″-O-galloyl)-rhamnoside (11), 2-hydroxybenzoic acid (13), 4-hydroxybenzaldehyde (14), vanillin (15), methyl 3,4-dihydroxybenzoate (16), 3,5-dihydroxybenzamide (18), tyrosol (19), caffeic acid (20), 3-(2,4,6-trihydroxyphenyl)-1-(4-hydroxyphenyl)-propan-1-one (21), phlorizin (22), friedelin (23), oleanolic acid (24), 4,4-dimethyl-heptanedioic acid (25), anthranilic acid (26), lumichrome (27), scoparone (28) and uracil (29) have not been recorded before in this plant. This is the first report on the occurrence of compounds 4–7, 9, 11, 13–14, 16, 18–21, 25–29 from the genus Rhus. Moreover, the chemotaxonomic significance of these isolated compounds was also summarized.