Phytochemical and chemotaxonomic study on Ficus tsiangii Merr. ex Corner

Thirty-four compounds, including ten coumarins (1–10), thirteen flavonoids (11–23), three triterpenoid, one lignanoid (24), seven triterpenes (25–31) and three other compounds (32–34), were isolated from the stems of Ficus tsiangii Merr. ex Corner (F. tsiangii). Their structures were identified as xanthyletin (1), coumarin (2), umbelliferone (3), isoangenomalin (4), dihydroxanthyletin (5), scopoletin (6), nodakenetin (7), 6,7-dihydroxy-coumarin (8), 4'-O-β- glucopyranosyl-3'-hydroxy-nodakenetin (9), 6-carboxy-umbelliferone (10), 5,7,4'-trimethoxy- 3'-hydroxy-aurone (11), apigenin (12), naringenin (13), genistein (14), luteolin (15), prunetin (16), chrysoeriol (17), 5,6,7,-trihydroxy-4'-methoxy-flavone (18), eriodictyol (19), isocarthamidin (20), 5,7,2',4'-tetrahydroxyflavone (21), taxifolin (22), dihydro-kaempferol (23), syringeresinol (24), taraxerol (25), taraxerone (26), lupeolacetate (27), 3-acetoxy-12- oleanene-11-ketone (28), 3-acetoxy-lup-12,20(29)-diene (29), oleanic acid (30), ursolic acid (31), 3,4,5-trimethoxy phenyl-1-O-glucopyranoside (32), 8'-hydroxyabscisic acid glucoside (33) and adenosine (34). Among them, all compounds except 3, 14, 17, 25, 26, 30, 33 were isolated from the plant for the first time, and compounds 1, 4, 5, 8–11, 16, 18, 20, 23, 24, 32, 34 were firstly reported from the genus Ficus. The chemotaxonomic significance of these compounds was summarized as follows.     

New steroid and other compounds from non-polar extracts of Clusia burle-marxii and their chemotaxonomic significance

Phytochemical investigation of the non-polar extract of Clusia burle-marxii led to the identification of a new steroid (1), along with friedelinol (2), β-sitosterol (3), friedelin (4), stigmast-5-en-3β,7β-diol (5), stigmast-5-en-3β,7α-diol (6), stigmasterol (7), sitostenone (8), betulinic acid (9), butyrospermol (10), euphol (11), betulin aldehyde (12), 2,2-dimethyl-5-hydroxy-7-phenyl-chromane (13), 6-deoxyisojacareubin (14), padiaxanthone (15) and betulonic acid (16). This is the first report of the identification of compounds 5, 6 and 10 in the family, the first report of compounds 14 and 15 in the genus, and the first report of compounds 2, 3, 7, 8, 12, 16 in the species. Chemotaxonomic significance of these compounds is described herein.     

Phytochemical investigation on the roots of Juglans mandshurica and their chemotaxonomic significance

Phytochemical research of the roots of Juglans mandshurica Maxim. (Juglandaceae) verified 37 secondary metabolites, including thirteen diarylheptanoids (1–13), five naphthoquinones (14–18), five tetralones (19–23), three lignans (24–26), three phenols (27–29), two anthraquinones (30–31), two triterpenoids (32–33), two secoiridoids (34–35), one naphthalenyl glycoside (36), and one flavonoid (37). The chemical structures of these constituents were elucidated by NMR spectroscopy and compared with data from the literature. This is the first confirmation of the presence of ten compounds (6, 12, 16, 18, 24–26, 30, 32–33) isolated from the family Juglandaceae, two compounds (1 and 8) from the genus Juglans, and four compounds (27, 31, 34–35) from J. mandshurica. The isolation and chemotaxonomic significance of the metabolites from the roots of J. mandshurica were described in this study.     

Chemical constituents from Polygonum capitatum Buch-Ham. ex D. Don

This work describes the isolation and characterization of thirty-one compounds from Polygonum capitatum Buch-Ham. ex D. Don, including two triterpenes (1–2), ten flavonoids (7–16), nine lignans (17–25), nine phenolic compounds (4–7, 26–31) and one anthraquinones (3). Their structures were elucidated on the basis of various spectroscopic methods (UV, IV and NMR, including 2D experiments). It was the first report of compounds 13, 15, 17, 24, 25, 28, 29, 30, 31 from the genus Ploygonum, and the first report of compounds 13, 15, 17, 24, 25 from the family Polygonaceae.     

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.     

Monoterpenoid indole alkaloids from Kopsia hainanensis Tsiang

A phytochemical investigation on the twigs and leaves of Kopsia hainanensis Tsiang resulted in the isolation and identification of 18 alkaloids, including two sarpagine type alkaloids (1 and 2), five eburnane type alkaloids (3–7), three aspidofractinine type alkaloids (8–10), one vincadine type alkaloid (11), three akuammiline type alkaloids (12–13 and 15), one corynanthean type alkaloid (14), two ajmalicine-like type alkaloids (16 and 17), and one aspidospermine type alkaloid (18). The new structure of compound 1 was elucidated by means of spectroscopic analysis, including HRESIMS, and 1D and 2D NMR experiments. Compounds 1–2, 4–5, 7, and 10–17 are herein reported for the first time from this plant, while the compounds 1, 2, 7, and 12–17 have not been previously recorded in the Kopsia genus. The chemotaxonomic significance and distribution of these monoterpenoid indole alkaloids in Kopsia genus are 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.     

Secondary metabolites from Corispermum mongolicum Iljin and their chemotaxonomic significance

A phytochemical investigation of the whole plant of Corispermum mongolicum Iljin (Chenopodiaceae) led to the isolation of thirty-eight compounds, including thirteen phenylpropanoids (1–13), six megastigmane-type norsesquiterpenoids (14–19), eight sterols (20–27), two flavonoid glycosides (28, 29), one alkaloid (30), two aromatic glycosides (31, 32), one aliphatic glycoside (33), one triterpenoid (34), one diterpenoid (35), two cerebrosides (36, 37) and one monogalactosyldiacyl glycerol (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. Twenty-eight compounds (1, 2, 4–16, 19, 20, 23–27, 30, 32–35, 37) were first found in the family Chenopodiaceae. The chemotaxonomic significance of these compounds is discussed.     

Solvent free,catalyst free,microwave or grinding assisted synthesis of bis-cyclic imide derivatives and their evaluation for anticancer activity

Cyclic imides are well known to be very important antitumor agents such as mitonafide and amonafide etc. Based on this fact, we have synthesized two series of cyclic imide derivatives containing two cyclic imide moiety in their structures (bis-cyclic imides) and screened them for in vitro anticancer activity against five human cancer cell lines i.e. breast (T47D), lung (NCl H-522), colon (HCT-15), ovary (PA-1) and liver (Hep G2). One series of bis-cyclic imide derivatives (3a–h) have been synthesized by condensation of acid anhydrides (1a–b) with diamines (2a–d) and another series (9a–f, 10a–f, 11a–f and 12a–f) by condensation of various diamines (4a–f) with diacids (5–8) in good yields. Structures assigned to 3a–h, 9a–f, 10a–f, 11a–f and 12a–f were fully characterized by spectroscopic means and elemental analysis. On screening for in vitro anticancer activity, compounds 3a (breast T47D), 3d (breast T47D, liver Hep G2), 3e (breast T47D, liver Hep G2), 3h (colon HCT-15), 10f (liver Hep G2) and 11a (colon HCT-15, ovary PA-1) exhibited good anticancer activities with IC₅₀ values range from 12.41 ± 3.2 to 17.9 ± 2.5 μM.     

Anti-inflammatory flavonoids from root bark of Broussonetia papyrifera in LPS-stimulated RAW264.7 cells

Broussonetia papyrifera has been used as a diuretic, tonic and suppressor of edema. Bioactivity-guided fractionation and metabolite investigation of root bark extracts of this plant resulted in the isolation and identification of six 1,3-diphenylpropanes (1, 2, 8, 10, 17, 20), flavanone (3), two chalcones (4, 5), five flavans (6, 11, 14–16), dihydroflavonol (7) and five flavonols (9, 12, 13, 18, 19), including five new compounds (5, 7, 8, 19, 20) that inhibit NO production in LPS-induced RAW264.7 cells. The structures of compounds 1–20 were elucidated on the basis of spectroscopic data (1D and 2D NMR, MS, MS/MS, and HRMS). In particular, compounds 3, 5, 7, 12, and 20 exhibited significant inhibitory effects on the NO, iNOS, and pro-inflammatory cytokine (TNF-α and IL-6) production. Therefore, this study suggests that the flavonoid-rich products of B. papyrifera, including the new compounds, could be valuable candidates for the development of pharmaceuticals or functional foods in the prevention and treatment of anti-inflammatory disease.     

Synthesis of benzensulfonamides linked to quinazoline scaffolds as novel carbonic anhydrase inhibitors

Carbonic anhydrase (CA) inhibitory activities of newly synthesized quinazoline-linked benzensulfonamides 10–29, 31, 32, 35, 36, and 45–51 against human CA (hCA) isoforms I, II, IX, and XII were measured and compared to that of acetazolamide (AAZ) as a standard inhibitor. Potent selective inhibitory activity against hCA I was exerted by compounds 14, 15, 17, 19, 20, 21, 24, 25, 28, 29, 31, 35, 45, 47, 49, and 51 with inhibition constant (K_Is) values of 39.4–354.7 nM that were nearly equivalent or even greater than that of AAZ (K_I, 250.0 nM). Compounds 15, 20, 24, 28, 29, 45 and 47 proved to have inhibitory activities against hCA II with (K_Is, 0.73–16.5 nM) that were similar or improved to that of AAZ (K_I, 12.0 nM). Compounds 13–29, 31–32, and 45–51 displayed potent hCA IX inhibitory activities (K_Is, 1.6–32.2 nM) that were more effective than or nearly equal to AAZ (K_I, 25.0 nM). Compounds 14, 15, 20, 21, 26, 45, and 47 exerted potent hCA XII inhibitory activities (K_Is, 5.2–9.2 nM), indicating similar CAI activities as compared to that of AAZ (K_I, 5.7 nM).     

Enantiomeric chromones from Harrisonia perforata

Six new chromones (1–3 and 7–9), along with 10 known ones, were isolated from the ethanol extract of Harrisonia perforata. The structures of the new compounds were elucidated by extensive spectroscopic and single crystal X-ray diffraction analyses. Compounds 1–3 and 8–9 are all racemates, and the corresponding enantiomers [(+)-1/2/3/8/9 and (−)-1/2/3/8/9] were obtained by chiral HPLC separation, respectively. The absolute configuration of (+)-1 was deduced by Mosher's method.     

Phytochemical and chemotaxonomic study on the leaves of Rhododendron dauricum L

The phytochemical study of the leaves of Rhododendron dauricum L. (Ericaceae) led to the isolation and identification of 44 compounds, including fourteen triterpenoids (1–14), thirteen flavonoids (15–27), eight phenols (28–35), four grifolin derivatives (36–39), two diterpenoids (40–41), two megastigmanes (42–43) and one sesquiterpenoid (44). The chemical structures of these compounds were identified by spectroscopic data and compared with those previously reported. This is the first report on compounds 25, 31, 34, 40, 43, and 44 from the family Ericaceae, compound 42 from the genus Rhododendron, and compounds 24, 28, 30, 32, 33 and 35 from R. dauricum. The chemotaxonomic significance of these compounds was discussed.     

Synthesis and molecular docking study of some 3,4-dihydrothieno[2,3-d]pyrimidine derivatives as potential antimicrobial agents

In continuation of our research program aiming at developing new potent antimicrobial agents, new series of substituted 3,4-dihydrothieno[2,3-d]pyrimidines was synthesized. The newly synthesized compounds were preliminary tested for their in vitro activity against six bacterial and three fungal strains using the agar diffusion technique. The results revealed that compounds 7, 8a, 10b, 10d and 11b exhibited half the potency of levofloxacine against the Gram-negative bacterium, Pseudomonas aeruginosa, while compounds 5a, 8b, 10c and 12 displayed half the potency of levofloxacine against Proteus Vulgaris. Whereas, compounds 7, 10b, 10d and 11b showed half the activity of ampicillin against the Gram-positive bacterium, B. subtilis. Most of the compounds showed high antifungal potency. Compounds 3, 6, 7, 9b, 10a, 11a, 11b, 15 and 16 exhibited double the potency of clotrimazole against A. fumigatus. While compounds 3, 4, 5a, 5b, 9b, 10a, 10b, 10c, 13, 15, 16 and 18 displayed double the activity of clotrimazole against R. oryazae. Molecular docking studies of the active compounds with the active site of the B. anthracis DHPS, showed good scoring for various interactions with the active site of the enzyme compared to the co-crystallized ligand.     

Cytotoxic withanolides from the aerial parts of Tubocapsicum anomalum

Ten new withanolides (1–10) and three artificial withanolides (11–13) were isolated from the aerial parts of Tubocapsicum anomalum, together with five known analogues (14–18). Their structures were determined on the basis of extensive spectroscopic and chemical methods. They include seven acnistin–type (1–4, 11, 14 and 15), three withajardin–type (5–7), and eight normal–type (8–10, 12, 13 and 16–18) withanolides. Of normal–type withanolides, a chemical conversion from the 16α,17α–epoxywithanolide (16) to Δ^13,14–16α–hydroxywithanolide (18) was achieved by Wagner–Meerwein rearrangement. All isolates were evaluated for their cytotoxicity against four human tumor cell lines (HCT–116, HepG2, MCF–7 and A375). Among them, compounds 1–3, 6–8, 14, 16–18 showed cytotoxic activity with IC₅₀ values of 0.24–8.71 μM.     

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.     

Chemical constituents of Melodinus hemsleyanus diels

Phytochemical investigation on the aerial parts of Melodinus hemsleyanus diels (Jahrb, Syst, 1995) led to the isolation and identification of 27 compounds, including fifteen aspidosperma-type alkaloids (1–15), four quinoline-type alkaloids (16–19), three quebrachamine-type alkaloids (20–22), and five eburna-type alkaloids (23–27). The structure of compound 1 was elucidated by means of spectroscopic analysis, including HRESIMS, and 1D and 2D NMR experiments. Compounds 1–2, 6, 10, 12, 13, 15, 16 and 20–27 are herein reported for the first time from the studied plant, while the compounds 1–2 and 21 have not previously been recorded in the genus Melodinus. The aspidosperma-type monoterpenoid indole alkaloids in M. hemsleyanus could serve as chemotaxonomic markers.     

Synthesis and docking studies of novel antitumor benzimidazoles

In this work, the benzimidazole-pyrrole conjugates 6a–h and benzimidazole-tetracycles conjugates 12–14 were prepared. The cytotoxicity of the compounds 3, 4a–h, 6a–h, 8, 10 and 12–14 was tested against lung cancer cell line A549. Compound 6b exhibited higher activity than the bis-benzoxazole natural product (UK-1), the standard. The tested 4g,h, 6a–h, 10 and 12–14 exhibited remarkable cytotoxicity activity against breast cancer cell line MCF-7 with higher activity than tamoxifen. Furthermore, compound 4h was found to be also more potent than doxurubicin. The antitumor promotion activity of synthesized compounds 4g,h, 6a–h, 10 and 12–14 has been estimated by studying their possible inhibitory effects on EBV-EA activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). Among the studied compounds, the inhibitory activities of compounds 8, 13 and 14 demonstrated strong inhibitory effects on the Epstein–Barr virus early antigen (EBV-EA) activation without showing any cytotoxicity on the Raji cells and their effects being stronger than that of a representative control, oleanolic acid.Moreover, the molecular docking of the new compounds into plasminogen activator (uPA) receptor has been in correlation with the antitumor activity. All synthesized compounds 3, 4a–h, 6a–h, 8, 10 and 12–14 were docked into same groove of the binding site of the native co-crystalized (4-iodobenzo[b]thiophene-2-carboxamidine) ligand (PDB code:1c5x) for activity explaination. Compounds 4h, 6b and 13, giving the best docking results, were further studied to estimate their effect on the level of uPA using AssayMax human urokinase (uPA) ELISA kit. In case of A549 cell line, compound 6 exhibited similar activity to MMC, and for MCF-7 cell line, compound 4h exhibited similar activity to doxorubicin, in inhibiting the expression of uPA.     

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 the roots of Fallopia convolvulus (L.) A. Löve

Twenty compounds, including three sterols (1–3), three phenols (4, 14 and 15), four anthraquinones (5, 7, 8 and 16), one chromone (6), two stilbenes (9 and 10), three amides (11–13), three flavonoids (17–19) and one organic acid (20), were obtained by modern phytochemical isolation methods. Their structures were identified by spectroscopic methods and in comparison with the published data in the references. Among them, compound 2, 3, 11 and 13 were firstly discovered from genus Fallopia, and compounds 1, 5–8, 10, 14, 15, 17, 19 and 20 were obtained from F. convolvulus for the first time. The chemotaxonomic significance of these compounds was also discussed, which revealed the relationships between F. convolvulus and some other species of Polygonaceae family.