Five New Norditerpenoid Alkaloids from Aconitum Sinomontanum

Abstract

From the roots of Aconitum sinomontanum, five new norditerpenoid alkaloids, sinomontanitines A (1) and B (2), sinomontanines A (3), B (4) and C (5), were isolated together with the known alkaloids lappaconitine (6) and ranaconitine (7), The structures of the new alkaloids were determined by spectral analysis.     

Phytochemical investigation of Tiarella polyphylla

Seven flavonoids (1–7), two triterpenoids (8 and 9) and four steroids (10, 11, 12 and 13) were isolated from the whole plant of Tiarella polyphylla. Based on the physicochemical and spectroscopic analyses, their structures were identified as myricetin (1), astragalin (2), afzelin (3), quercitrin (4), myricitin (5), nicotiflorin (6), isoquercitrin (7), tiarellic acid (8), 3β-hydroxy-20(29)lupen-27-oic acid (9), β-sitosterol-3-O-β-D-glucoside (10), stigmasterol-3-O-β-D-glucoside (11), β-sitosterol (12) and ergosterol endoperoxide (13). All 13 compounds, with the exception of tiarellic acid were isolated for the first time from T. polyphylla. In the anti-complementary assay, the steroids (12 and 13) exhibited potent activities; whereas, the flavonoids (1 to 7) showed weak or no activities, but even the triterpenoids (8 and 9) and steroidal saponins (10 and 11) evoked hemolysis.     

Heteroclitin H,a new lignan from Kadsura heteroclita

A new dibenzocyclooctadiene lignan, heteroclitin H (1), was isolated together with seven known compounds, heteroclitin D (2), interiorin B (3), interiorin (4), neokasuranin (5), interiotherin C (6), gomisin J (7) and (+)-anwulignan (8), from the stems of Kadsura heteroclita. Their structures were elucidated by spectroscopic methods. This is the first report of the isolation of compounds 3, 5, 6, 7 and 8 from K. heteroclita.     

Preparation and antitussive,expectorant, and antiasthmatic activities of verticinone's derivatives

To prepare verticinone derivatives with significant antitussive, expectorant, and antiasthmatic activities, the compounds 3β-acetylverticinone (1), 3-ketoverticinone (2), 3β-benzoylverticinone (3), 3β-propionylverticinone (4), 3β-butyrylverticinone (5), and 3β-butoxycarbonylverticinone (6) have been prepared. All of these are new compounds. Among them, 1–6 exhibited potent antitussive and expectorant activities; 1 and 3–6 displayed various antiasthmatic activities. The antitussive activity of 1–6, the expectorant activity of 1–2 and 4–6, and the antiasthmatic activity of 1 are higher than those of verticinone. The results demonstrated that 1 had dominant biological activities, suggesting that it would be a potential antitussive, expectorant, and antiasthmatic agent.     

A new ferulic acid ester and other constituents from Dracocephalum peregrinum

A new ferulic acid ester, 1′-methyl-2′-hydroxyethyl ferulate (1), together with methylcaffeate (2), 4-hydroxy cinnamic acid (3), ferulic acid (4), caffeic acid (5), diosmetin (6), luteolin (7), 5,3′,4′-trihydroxy-3,7-dimethoxyflavone (8), eriodictyol (9), kaempferol (10), quercetin (11), acacetin-7-O-glcopyranoside (12), 4-(β-glucopyranosyloxy) benzoic acid (13), luteolin-7-O-(6″-feruloyl) glucopyranoside (14), luteolin-7-O-glucopyranoside (15), kaempferide-3-O-rhamnopyranoside (16), quercitrin (17), kaempferol-3-O-glucopyranoside (18), prunasin (19), quercetin-7-O-glucopyranoside (20), quercetin-3-O-glucopyranoside (21), plantaginin (22), linarin (23), luteolin-7-O-rutinoside (24), and chlorogenic acid (25) were isolated from the aerial parts of Dacocephalum peregrinum. The structure of 1 was elucidated on the basis of spectroscopic and HR-ESI-MS analyses. In addition, compound 1 exhibited mild inhibitory effect on NO production in LPS-stimulated RAW264.7 cells.     

Two new lignan glucosides from the fruit of <Emphasis Type="Italic">Vitex cannabifolia</Emphasis>

Two new phenyldihydronaphthalene-type lignan glucosides, vitecannasides A (1) and B (2) were isolated from the fruit of Vitex cannabifolia Sieb. et. Zucc. (Verbenaceae) along with the six known lignan derivatives (3–8), four known iridoid glucosides (9–12), three known flavonoids (13–15), and one known phenylbutanone glucoside (16). Their chemical structures were determined on the basis of spectroscopic data as well as chemical evidence. The scavenging effect of 1, 2, and 11–16 on the stable free radical 1,1-diphenyl-2-picrylhydrazyl was examined. Compounds 1, 2, 14, and 15 exhibited stronger activity than that of l-cysteine. Especially, 14 and 15 showed more potent activity than that of α-tocopherol.     

Benzoin in heterocyclic synthesis: Synthesis and reactions of 2,3-Diphenyl-4-cyanopyrrole-5-thione

2,3-Diphenyl-4-cyano-pyrrole-5-thione (4) was prepared either by the reaction of benzoin (1) and cyanothioacetamide (3) followed by cyclization using AcOH/sodium acetate or by refluxing a mixture of benzoin (1) and cyanothioacetamide in pyridine to afford directly4. Several new pyrrole and pyrazole derivatives were synthesised using4 as synthon. The structure of the newly synthesised derivatives were based on celemental and spectral data studies. Methylation of the SH group in4 afforded5. Reaction of4 with ethyl bromo acetate afforded (6). Treatment of (5) and (6) with hydrazine hydrate afforded the same pyrazole derivative (10) through the intermediate (9). Treatment of6 with aniline and phenylhydrazine afforded the pyrrole derivatives8a,b respectively. Treatment of6 while dil HCl gave 2,3-diphenyl-4-cyano-pyrrole-5-one (7). Treatment of6 with NH₃/EtOH afforded the amidic derivatives (11) with treatment of6 with NH₃/heat then acidification it gave the carboxylic derivatives (12).     

Alkaloids from the hook-bearing branch of Uncariarhynchophylla and their neuroprotective effects against glutamate-induced HT22 cell death

One new alkaloid, 4-geissoschizine N-oxide methyl ether (1), was isolated from the EtOH extract of the hook-bearing branch of Uncariarhynchophylla, together with 10 known alkaloids, 3-epi-geissoschizine methyl ether (2) isolated from U.rhynchophylla for the first time, geissoschizine methyl ether (3), 4-hirsuteine N-oxide (4), hirsuteine (5), hirsutine (6), 3α-dihydro-cadambine (7), 3β-isodihydro-cadambine (8), cadambine (9), strictosamide (10), and akuammigine (11). The structures were elucidated by spectroscopic methods including UV, ESI-QTOF MS, NMR, and circular dichroism experiments. Neuroprotective effects of 1–9 were investigated against 3 mM glutamate-induced HT22 cell death. The activity assay showed that 2, 3, 5, and 6 exhibited potent neuroprotective effects against glutamate-induced HT22 cell death. However, only weak neuroprotective activities were observed for 1, 4, 7, 8, and 9.     

Polyphenolic compounds from the leaves of Koelreuteria paniculata Laxm

From the fresh leaves of Koelreuteria paniculata Laxm (Sapindaceae), four new compounds, named ethyl p-trigallate (1), 3"-O-galloyl-4'-O-galloyl-4-O-galloyl-gallic acid (2), ethyl p-heptagallate (3) and 3"-galloylquercitrin (4), together with 12 known compounds namely catechin (5), galloylepicatechin (6), isorhamnetin (7), kaempferol-3-O-arabinopyranoside (8), quercetin-3'-O- g -D-arabinopyranoside (9), quercitrin (10), methyl p-digallate (11), methyl m-digallate (12), p-digalloyl acid (13), m-digalloyl acid (14), hyperin (15) and kaempferol-3-O- f -L-rhamnoside (16) were isolated by extensive column chromatographic separation. Their structures were elucidated on the basis of chemical and spectroscopic methods. Compound 9 was not reported previously with pyranoside of arabinose at C-3'. Compounds 4 and 9 possessed the activity for PTK inhibition.     

A New Bicoumarin from Stellera Chamaejasme L

Abstract

Thirteen compounds were isolated from roots of Stellera chamaejasme L. (Thymelaeaceae). They are β-sitosterol (2), simplexin (3), pimelea factor P2 (4), daucosterol (5), (+)-3-hydroxy-1,5-diphenyl-1-pentanone (6), 4-ethoxy-benzoic acid (7), 2,4,6-Trimethoxy-benzoic acid (8), (+)-afzelechin (9), fumaric acid (10), N,N-dimethyl-L-aspartic acid (11), umbelliferone (12), daphniretin (13) and a novel bicoumarin named bicoumastechamin (1). Among the known compounds, 7, 8, 9, 10 and 11 were first isolated from this plant, and 6 was first isolated from the natural resources. Their structures have been elucidated on the basis of spectral data. In vitro bioassays showed that 4 inhibited cancer cell growth, 13 exhibited immunomodulatory activity, and 6 exhibited both immunomodulatory and anti-tumor activity.     

A new phenylethanoid glycoside from the fruits of <Emphasis Type="Italic">Callicarpa japonica</Emphasis> Thunb. var. <Emphasis Type="Italic">luxurians</Emphasis> Rehd.

A new phenylethanoid glycoside, named acetyl forsythoside B (1), was isolated from the fruits of Callicarpa japonica Thunb. var. luxurians Rehd. (Verbenaceae) along with forsythoside B (2), brandioside (3), poliumoside (4), actioside (5), and apigenin 7-galacturonide (6). The structures of 1–6 were determined on the basis of spectroscopic data. In addition, the antioxidative activity of 1–4 and 6 was evaluated by the ferric thiocyanate method. All of the tested compounds except 6 exhibited almost the same activity as 3-tert-butyl-4-hydroxyanisole. The radical-scavenging effect of 1–6 on the stable free radical 1,1-diphenyl-2-picrylhydrazyl was also examined. Compounds 1–5 showed almost twice the activity compared to α-tocopherol.     

Antifungal Diterpenoids and Flavonoids from Ballota inaequidens.

ABSTRACT

Two diterpenoids (hispanolone 1, ballonigrine 2) and six flavonoids (5-hydroxy-3,7,4′-trimethoxyflavone 3, retusin 4, 5-hydroxy-7,4′-dimethoxyflavone 5, pachypodol 6, 5-hydroxy-3,6,7,4′-tetramethoxyflavone 7, 5-hydroxy-7,3′,4′-trimethoxyflavone 8) have been isolated from the aerial parts of Ballota inaequidens. Hub.-Mor. & Patzak. Among them, 7 has not been reported previously in the genus Ballota.. The antibacterial and antifungal activities of 1–4, 6, and 8 were tested against Bacillus subtilis., Staphylococcus aureus., Escherichia coli., Pseudomonas aeruginosa., Candida albicans., and Candida crusei..     

A new triterpenoid from <Emphasis Type="Italic">Brucea javanica</Emphasis>

A new triterpenoid, bruceajavanin C (1), together with bruceosides A and B (2 and 3), bruceines D and E (4 and 5), yadanziosides A and G (6 and 7), (20R)-O-(3)-α-L-arabinopyranosylpregn-5-ene-3β,20-diol (8), and α-D-glucopyranoside, (3β, 20R)-3-hydroxypregn-5-en-20-yl (9) were isolated from the aerial parts of Brucea javanica. The structure of 1 was elucidated on the basis of 2D-NMR spectroscopic analysis. In addition, compounds 1, 3, 4, 5, and 6 exhibited mild inhibitory effect on NO production in LPS-stimulated RAW264.7 cells.     

Conventional and microwave-assisted synthesis of imidazole and guanidine derivatives and their biological evaluation

A number of imidazole derivatives 3a–f and 4a–f have been synthesized by the condensation of 3-methylthiophen-2-carboxaldehyde 1a, 5-methylthiophen-2-carboxaldehyde 1b, N-methylpyrrol-2-carboxaldehyde 1c, 1-naphthaldehyde 1d, 2-naphthaldehyde 1e, and 2-hydroxy-1-naphthaldehyde 1f with 1,2-diaminoanthraquinone 2a and 2,3-diaminophenazine 2b, respectively. Condensation of 2-guanidinobenzimidazole with functionalized aldehydes 1a–f leads to the formation of guanidine derivatives 5a–f. Both imidazole (3a–f, 4a–f) and guanidine derivatives (5a–f) were synthesized in good yields using conventional heating and microwave irradiation techniques. Structures assigned to compounds 3a–f, 4a–f and 5a–f are supported by correct spectral and analytic data. On screening for anti-inflammatory and anticancer activities, compounds 3e, 4a and 5a exhibited good anti-inflammatory and compounds 3d, 3f, 4d and 4f showed very good anticancer activity.     

Chemical constituents of Euonymus fortunei

A new flavonol glycoside, kaempferol-3-O-β-d-(2-O-E-p-coumaroyl)-glucopyranosyl-7-O-α-l-rhamnopyranoside (1), along with eleven known compounds including five flavonol glycosides (2–6), one phenolic glycoside (7), two megastigmane glycosides (8 and 9), two triterpenoids (10 and 11) and one alditol (12), was isolated from the aerial parts of Euonymus fortunei. Their structures were determined on the basis of spectroscopic analysis and chemical evidence. Compounds 2–4, 7, 8, and 10–12 were evaluated their antimicrobial activities against Ureaplasma urealyticumin vitro, but all tested compounds have no useful activities against Ureaplasma urealyticum.     

Bioactivity-guided synthesis of gramine derivatives as new MT1 and 5-HT1A receptors agonists

Twenty-four gramine derivatives were synthesized and evaluated on MT₁ and 5-HT_1A receptors in vitro. Among them, seven derivatives (7, 8, 16, 19, 20, 21, and 24) exhibited higher agonisting activities on MT₁ or 5-HT_1A receptors. Compared with gramine, derivatives 7, 8, 16, 19, 20, 21, and 24 displayed 1.6–3.5-fold increase in agonistic rates on 5-HT_1A receptor. Particularly, derivatives 7, 19, and 21 exhibited significant agonistic activities on MT₁ and 5-HT_1A receptors with EC₅₀ values of 0.51, 0.39, 0.50 mΜ and 0.28, 0.46, 0.23 mΜ, respectively. The preliminary structure–activity relationships of gramine derivatives were summarized for further investigation on MT₁ and 5-HT_1A receptors as new potential agonists.     

Five new compounds from Dendrobium crystallinum

Five new compounds, dencryol A (1), dencryol B (2), crystalltone (3), crystallinin (4), and 3-hydroxy-2-methoxy-5,6-dimethylbenzoic acid (5), together with six known compounds, dendronobilin B (6), syringic acid (7), apigenin (8), isoviolanthin (9), 6?-glucosyl-vitexin (10), and palmarumycin JC2 (11), have been isolated from the stems of Dendrobium crystallinum, of which compounds 9–11 were isolated from the genus Dendrobium for the first time, and all the other compounds were first obtained from this plant. Their structures were established on the basis of spectroscopic analysis and literature data.     

A new dimeric phenylpropanoid and cytotoxic norditerpene constituents from Podocarpus nakaii

A new dimeric phenylpropanoid namely podonaka A (1), along with the 13 known compounds including diterpenes (2 and 3), norditerpenes (4 and 5), benzenoids (6–10), steroids (11 and 12), chalcone (13), and megastigmane (14), was isolated from the EtOH extract of Podocarpus nakaii Hayata. The structure of 1 was elucidated on the basis of spectroscopic analysis including 1D and 2D NMR and MS techniques. Biological evaluation showed that norditerpenes, inumakilactone B (4), and podolactone E (5) have potent cytotoxic activities against Daoy, WiDr, KB, and HeLa tumor cell lines. Moreover, low dosage of 5 may induce early apoptosis in KB cells before 12 h.     

Antifungal Flavonoids from Ballota glandulosissima

Abstract

The flavonoids kumatakenin (1), pachypodol (2), 5-hydroxy-7,3′,4′-trimethoxyflavone (3), velutin (4), salvigenin (5), retusin (6) and corymbosin (7) have been isolated from the aerial parts of Ballota glandulosissima Hub.-Mor & Patzak. Among them, 2–4 and 7 have not been reported previously in the genus Ballota. The antibacterial and antifungal activities of 1–4 and 6 were tested against Bacillus subtilis, Staphylococcus aureus, Staphylococcus faecalis, Echerichia coli, Pseudomonas aeruginosa, Candida albicans, Candida krusei and Candida galabrata.     

New isoflavones from Belamcandae Rhizoma

Four new isoflavones (iristectrigenin A-7-glucoside (2), 8-hydroxytectrigenin (5), 8-hydroxyiristectrigenin A (6), and 8-hydroxyirigenin (7–1) have been isolated from Belamcandae Rhizoma (the rhizome of Belamcanda chinensis), along with nine known compounds: tectridin (1), tectrigenin-4′-glucoside (3), astragalin (4), irilin D (7–2), isotectrigenin (8), tectrigenin (9), iristectrigenin B (10), hispiludin (11–1), and irigenin (11–2). The structures of 2, 5, 6 and 7–1 were determined by spectroscopic methods, including high-resolution mass spectrometry (HR-MS), proton nuclear magnetic resonance (¹H-NMR), carbon-13 NMR (¹³C-NMR), and various two-dimensional (2D)-NMR techniques.