Phytochemical and chemotaxonomic study on Ziziphus Jujuba Mill. (Rhamnaceae)

Fourteen compounds were isolated from fruits of Ziziphus jujuba Mill., including two flavonoids (1–2), one phenolic glycosides (3), one lignan (4), four phenols (5–8), three alkaloid (9–10, 14), three sesquiterpenoid (11–13). The structures of all the compounds were established by the NMR techniques, as well as by comparison with previously reported data in literature. Compounds 2″-glucosyl-8-C-glucosyl-4′-O-methylapigenin (1), 3′, 4′, 5′-trimethoxycinnamyl alcohol (5), 2-{4-[(1E)-3-Hydroxyprop-1-en-1-yl]-2, 6-dimethoxy-phenoxy}propane-1, 3-diol (6), 1-(4-Hydroxyphenyl)ethane-1, 2-diol (8), (1S, 3S)-1-Methyl-l, 2, 3, 4-tetrahydro-β-carboline-3-carboxylic acid (9), (1R, 3S)-1-Methyl-l, 2, 3, 4-tetrahydro-β-carboline-3-carboxylic acid (10), grasshopper ketone (12), methyl (3R, 5R)-5-methoxy-3-phenylisoxazolidine-5-carboxylate (14) were firstly reported from the genus Ziziphus and the family Rhamnaceae. Furthermore, the chemotaxonomic significance of the isolates was discussed.     

Phytochemical and chemotaxonomic study on Saussurea medusa Maxim. (Compositae)

A phytochemical investigation of Saussurea medusa Maxim. led to the isolation of eleven compounds, including neoechinulin A (1), 8-hydroxypinoresinol (2), caruilignan D (3), 7(S)-hydroxyarctigenin (4), pinoresinol (5), arctigenin (6), arctii (7), epipinoresinol (8), loliolide (9), apigenin (10), and luteolin (11). Their structures were elucidated by spectroscopic methods and comparison with previously reported spectral data. Among them, compounds 1 and 2 were firstly obtained from this species, compounds 3 and 4 were isolated from the genus Saussurea for the first time. Furthermore, the chemotaxonomic significance of these compounds was discussed in details.     

Chemical constituents from Gentianella turkestanorum (Gentianaceae)

Phytochemical investigation of Gentianella turkestanorum (Gentianaceae) afforded nineteen compounds, including six xanthones (1–6), two triterpenoids (7–8), eight flavones (9–16) and three iridoids (17–19). Here, we firstly reported that 1-hydroxy-3,5-dimethoxyxanthone (4), 1, 8-dihydroxy-3-methoxyxanthone (5), apigenin (9), quercetin (10), luteolin-7-O-glucoside (12) and three other compounds (1, 8-dihydroxy-3-methoxyxanthone (5), apigenin-7-O-gluco (1″ → 3‴) glucoside (15) and luteolin-7-O-gluco (1″ → 3‴) glucoside (16)) could be isolated from G. turkestanorum. The occurrence of chemical data and the sequence data might be employed as common constituents of the genera Gentianella, Lomatogonium and Swertia.     

Chemical constituents from Striga asiatica and its chemotaxonomic study

Six flavonoids, diosmetin (1), apigenin (2), luteolin (3), chrysoeriol (4), apigenin-7-O-glucuronide (5) and acacetin (6), two caffeic acid sugar esters, verbascoside (7) and isoverbascoside (8), as well as one norsesquiterpene, blumenol A (9) were isolated or detected from the EtOAc and n-BuOH extract of the whole plants of Striga asiatica. Their structures were identified by ¹H & ¹³C NMR, HR-LC-TOF-MS and co-injection with the reference standards. Among them, blumenol A (9) was firstly found from the Scrophulariaceae. Diosmetin (1) and isoverbascoside (8) were firstly reported from the genus Striga, while verbascoside (7) was reported from this plant for the first time. Based on our chemotaxonomic studies and the previous phytochemical studies on Scrophulariaceae, Striga could be tentatively treated as a member of the family Scrophulariaceae instead of Orobanchaceae.     

Phytochemical and chemotaxonomic study on Fallopia dentatoalata (Fr. Schm.) Holub

Phytochemical study of Fallopia dentatoalata gave seventeen compounds, two sterols (8 and 10), three anthraquinones (5, 16 and 17), one chromone (13), two stilbenes (3 and 4), two amides (11 and 12), six flavonoids (1, 2, 6, 7, 14 and 15) and one fatty acid (9). Their structures were elucidated by spectroscopic methods and in comparison with the reported data. Compound 11 was obtained from genus Fallopia for the first time, and all of the compounds were firstly isolated from F. dentatoalata. The chemotaxonomic significance of these compounds was also discussed, which demonstrated the relationships between F. dentatoalata and some other species of genus Fallopia.     

New purine alkaloids from the Red Sea marine tunicate Symplegma rubra

Investigation of the Red Sea marine tunicate Symplegma rubra Monniot, 1972 gave three new purine alkaloids namely 6-methoxy-7,9-dimethyl-8-oxoguanine (1), 6-methoxy-9-methyl-8-oxoguanine (2), and 2-methoxy-7-methyl-8-oxoadenine (4) together with seven known compounds: 6-methoxy-7-methyl-8-oxoguanine (3), 9-methyl-8-oxoadenine (5), 7-methyl-8-oxoadenine (6), 8-oxoadenine (7), 3-methylxanthine (8), inosine (9), and homarine (pyridinium-2-carboxylic acid-1-methyl) (10). Compound 6 was reported here for the first time from a natural source. The structure determination of the compounds was accomplished by extensive interpretation of their spectroscopic data including 1D (¹H and ¹³C) and 2D (¹H–¹H COSY, HSQC, and HMBC) NMR and high-resolution mass spectral data. The isolated compounds were evaluated for their protein kinase inhibitory activity against different kinases (CDK5, CK1, DyrK1A, and GSK3) at 10 μg/mL. The compounds showed moderate activity against these kinases.     

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.     

Phytochemical and chemotaxonomic study on Dianella ensifolia (L.) DC

Phytochemical investigation of the roots of Dianella ensifolia led to the isolation of eleven known compounds, including two aromatics (1, 2), two chromones (3, 4), and seven flavonoids (5–11). The structures of these compounds were elucidated on the basis of spectral analysis and comparison with data reported in literature. In the present research, all of the isolated compounds 1–11 were reported for the first time in the species D. ensifolia. Compounds 1–4 and 7–11 were firstly isolated from the genus Dianella. Compounds 1, 2, 8, and 9 have not been reported from any species in Liliaceae family. The chemotaxonomic significance of the isolated compounds was summarized.     

Phytochemical and network-based chemotaxonomic study of Lonicera japonica Thunb

Phytochemical research on the flower buds of Lonicera japonica Thunb. led to the isolation of 15 compounds, including nine terpenoids (1–9), three phenylpropanoid glycosides (10–12), two alkyl glycosides (13–14) and an alkaloid (15). The structures of these compounds were determined by NMR spectroscopy and comparison with data from previous literatures. Among them, eleven compounds (2–5, 8, 10 and 11–15) were reported from the genus Lonicera for the first time and compounds 3, 4, 5, 10 and 11–15 were firstly reported from the family Caprifoliaceae. Network analysis was carried out to explore the chemotaxonomic significance of these compounds for L. japonica in this study.     

Chemical constituents from the leaves of Cinnamomum parthenoxylon (Jack) Meisn. (Lauraceae)

Phytochemical investigation of the ethanolic extract from the leaves of Cinnamomum parthenoxylon (Jack) Meisn. led to the isolation of (3R, 4R, 3′R, 4′R)-6,6′-dimethoxy-3, 4, 3′, 4′-tetrahydro-2H, 2′H-[3, 3′]bichromenyl-4, 4′-diol (1), 4-hydroxybenzaldehyde (2), 1,2,4-trihydroxybenzene (3), kaempferol-3-O-α-l-rhamnoside (4), herbacetin (5), quercetin-3-O-α-l-rhamnoside (6), daucosterol (7), and β-sitosterol (8). The structures were established by extensive analysis of their MS and NMR spectroscopic data and comparison with literature data. In the present research, all of the isolated compounds 1–8 are reported for the first time in the species C. parthenoxylon. Compounds 1–6 were firstly isolated from genus Cinnamomum. Compounds 1, 3, 5 and 6 have not been reported from any species in Lauraceae family. The chemotaxonomic significance of the isolated compounds is discussed.     

Phenolic constituents from the roots of Rosa laevigata (Rosaceae)

Chemical investigation of the root of Rosa laevigata led to the isolation of sixteen phenolic compounds, including seven flavonoids (1–7), five condensed tannins (8–12), two stilbenes (13 and 14) and two benzoic acid derivatives (15 and 16). Their structures were identified as (+)-catechin (1), (+)-gallocatechin (2), (2R, 3S, 4S)-cis- leucocyanidin (3), (2R, 3S, 4S)-cis-leucofisetinidin (4), (2S, 3R, 4R)-cis- leucofisetinidin (5), dehydrodicatechin A (6), phloridzin (7), procyanidin B3 (8), fisetinidol-(4α, 8)-catechin (9), guibourtinidol- (4α, 8)-catechin (10), ent- isetinidol -(4α, 6)-catechin (11), fisetinidol-(4β, 8)-catechin (12), (Z)-3-methoxy-5-hydroxy- stilbene (13), (Z)-piceid (14), gallic acid (15) and 4-hydroxybenzoic acid- 4-O-β-D-glucopyranoside (16). Among them, compounds 3–7, 9–14, and 16 were isolated from R. laevigata for the first time, and compounds 3–7, 9, 10, 12–14 and 16 were reported for the first time from the genus Rosa. The chemotaxonomic significance of these compounds was summarized.     

Chemical constituents from the fruits of Amomum kravanh

Chemical investigation of the traditional Chinese medicine Amomum kravanh led to the isolation of a new secolignan (1), two flavonoids (2 and 3), four monoterpenoids (4–7) and six steroids (8–13). Compounds 1, 5–8 and 12–13 were isolated from the family Zingiberaceae for the first time. Compound 1 is the first lignan reported in the genus Amomum and compound 8 is firstly described as a natural product, which could be of chemotaxonomic importance for the genus Amomum and family Zingiberaceae.     

A new bicyclic sesquiterpenoid from Merremia yunnanensis

A new sesquiterpenoid, 1α,4β,8β,9β-eudesmane-tetrol-1-O-β-D-glucopyranoside (1), together with nine known compounds (2–10), were isolated from Merremia yunnanensis. The structures of these compounds were elucidated by spectroscopic methods and compared to data in the literature. All these compounds (1–10) were firstly isolated from this plant, and compounds 3, 5, 7, and 10 were reported from the Merremia genus for the first time. The significance of the chemotaxonomy for these compounds is described herein.     

Chemical constituents of Euphorbia peplus

Phytochemical investigation of the whole plant of Euphorbia peplus Linn. led to the isolation of previously uncharacterized jatrophane type diterpenoid euphopepluanone L (1), along with seven known compounds, including three diterpenes (2–4), three bisnorsesquiterpenes (5–7), and a monoterpene (8). Their chemical structures were established based on extensive spectroscopic analysis. Compounds 3 (20-deoxyingenol) and 5–8 were firstly isolated from E. peplus, while PBI 345 (5) reported from the genus for the first time. Furthermore, the chemotaxonomic significance of the isolates was discussed.     

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.     

Phytochemical investigation on the fruiting body of Russula aruea Pers

Phytochemical investigation of ethyl acetate fraction from Russula aruea Pers fruiting body led to the isolation and identification of one new isolactarane sesquiterpene (1) and 11 known compounds, including four sesquiterpenes (2-5), four sterols (6–9), one allitol (10), and two fatty acids (11–12). The structure of compound 1 was elucidated by means of spectroscopic analysis, including 1D and 2D NMR, HR-ESI-MS, and X-Ray experiments. Compounds 1–3 and 5–12 are herein reported for the first time from Russula genus, while compound 4 is firstly described in R. aruea. The sesquiterpenes in R. aruea could serve as chemotaxonomic markers.     

Anthraquinones and other constituents from the roots of Eremomastax speciosa (Hochst.) Cufod

The chemical investigation of the roots of Eremomastax speciosa (Hochst.) Cufod (Acanthaceae). led to the isolation of thirteen compounds including five anthraquinones 1,8-dihydroxy-3-methylanthraquinone (1), 1,8-dihydroxy-3-methoxy-6-methylanthraquinone (2), emodin (3), aloe emodin (4) and 8-O-D-glucopyranosideemodin (5); one phenylethanoid glucoside acteoside (6); one benzophenone 2,6-dimethoxybenzophenone (7); two pentacyclic triterpenoids lupeol (8) and betulinic acid (9); three phytosterols stigmasterol (10), β-sitosterol (11), and β-sitosterol-3-O-β-D-glucopyranoside (12) and one fatty acid hexadecanoid acid (13). All these compounds are firstly reported from the roots of E. speciosa. Emodin and acteoside were modified chemically through allylation reaction to afford 3-O-allylated emodin (3a) and a new perallylated acteoside derivative (6a), respectively. The structure of the isolated compounds as well as those of the allylated derivatives were established by means of spectroscopic methods: NMR analysis (¹H and ¹³C NMR, ¹H–¹H–COSY, HSQC and HMBC), high-resolution mass spectrometry (HR-ESI-MS) and by comparison with previously reported data. All those compounds were tested for their cytotoxic activity against the human cervix carcinoma KB-3-1 cells and their antioxidant activity, the allylated acteoside derivative and 2,6-dimethoxybenzophenone showed weak cytotoxicity while acteoside showed a good antioxidant activity. In addition, the chemotaxonomic significance of the isolated compound is discussed.     

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.     

Chemical constituents from the pericarps of Zanthoxylum bungeanum and their chemotaxonomic significance

The phytochemical study of the pericarps of Zanthoxylum bungeanum Maxim under the guidance of bioactivity led to the isolation of 18 compounds, including a new isobutylhydroxyamide (1) and 17 known compounds, i.e. six alkylamides (2–7), five coumarins (8–12), one benzene derivative (13), three flavonoids (14–16), and two sterols (17–18). Their structures were elucidated based on extensive spectroscopic methods (HRESIMS, 1D and 2D NMR experiments) and by comparison with literature data. New compound (1) and known compound (2) are cis-trans isomeric isobutylhydroxyamides. Among them, compounds 9, 10, and 12 were isolated for the first time from Z. bungeanum, compound 11 was firstly recovered from the genus Zanthoxylum, and compound 14 was reported for the first time from the Rutaceae family. The chemotaxonomic significance of isolated compounds from Z. bungeanum is discussed.     

Phytochemical and chemotaxonomic study on the Lichen Lethariella cladonioides

The comprehensive phytochemical research of Lethariella cladonioides (Nyl.) Krog, (Parmeliaceae), a lichen in southwest China, resulted in isolation of eighteen compounds (1–18), including a new phenolic acid 3,5-dihydroxy-4-methylbenzaldehyde (1) and seventeen known compounds, nine phenolic acids (2–10), one dibenzofuran (11), two depsides (12 and 13), one alkane (14), one glucoside (15), two polyols (16 and 17), and one fatty acid (18). The structures of these compounds were assigned by detailed interpretations of spectroscopic data (1D and 2D NMR, HR-ESI-MS) and comparisons with the published data. Among them, 3,5-dihydroxy-4-methylbenzaldehyde (1) is a new one. (−)-hydroxypropan-2′,3′-diol-orsellinate (10) have not been reported from any species in the lichens. Compounds 6, 7, 9, 12, 14, 16 and 18 were firstly isolated from the genus Lethariella (Motyka) Krog. Compounds 2, 6, 7, 9, 10, 12, 14, 16 and 18 were reported from L. cladonioides firstly. The chemotaxonomic significance of these compounds was also discussed.