Brunonianines D-F, three new C19-diterpenoid alkaloids from the Delphinium brunonianum, with therapeutic effect on ovarian cancer in vitro and in vivo.

The current standard treatment for ovarian cancer consists of surgery to reduce the size of the tumor, followed by treatment with chemotherapeutic drugs, which have major side effects. Therefore, finding a new natural product drug with fewer side effects is a strategy. Delphinium brunonianum (D. brunonianum) is a traditional Tibetan medicine, mainly from southern Tibet, China, whereas the chemical constituents in this plant remain elusive. The major metabolites in the dichloromethane fraction of D. brunonianum were analyzed and purified by HPLC and various column chromatography techniques. Nine diterpenoid alkaloids (1-9) and one amide alkaloid (10) were isolated from D. brunonianum, including three novel C19-type diterpenoid alkaloids (Brunonianines D-F) (1-3). Their structures were elucidated by 1D/2D NMR, HR-ESI-MS and single-crystal X-ray diffraction analyses. All compounds were evaluated for toxicity in four tumor cell lines. Most of the compounds exhibited potent inhibitory effects on Skov-3 cell lines, with IC50 values ranging from 2.57 to 8.05 µM. The western blotting experiment was used to further analyze the expression levels of molecules in the Bax/Bcl-2/Caspase-3 signaling pathway for compound 1. Molecular docking was performed to predict the binding modes of Brunonianine D with target proteins. In vivo experiments were also performed and evaluated in real time by monitoring the size of the Skov-3 tumor. Additionally, tumor H&E staining and the TUNEL assay used to evaluate anti-tumor effects.

Diterpenoid Alkaloids from Delphinium ajacis and Their Anti-inflammatory Activity.

Three novel diterpenoid alkaloids, comprising two C19 -diterpenoid alkaloids (1 and 2) and one C20 -diterpenoid alkaloid (3), were isolated from Delphinium ajacis, alongside the six known compounds (4-9). Their structures were elucidated by spectroscopic methods (MS, UV, IR, 1D and 2D NMR) and chemical properties. Simultaneously, the anti-inflammatory properties of all compounds (1-9) was conducted, focusing on nitric oxide (NO) production in LPS-induced BV-2 cells. The results indicated compounds 1-3, 7, and 8 have potential anti-inflammatory activity.

Diterpenoid Alkaloids from Delphinium liangshanense.

Two new C19-diterpenoid alkaloids of the lycoctonine-type (liangshanine A and liangshanine B) and nineteen known compounds (3-21) were isolated from the whole plant of Delphinium liangshanense W. T. Wang, and all the compounds were identified by different spectroscopic analyses, such as IR, HR-ESI-MS and NMR. All the compounds were isolated from this plant for the first time and tested for the anti-proliferation effects on MH7 A and SF9 cells to figure their anti-rheumatoid arthritis and anti-insect activity, but none of them showed remarkable activity.

Two New C19 -Diterpenoid Alkaloids from Delphinium shawurense.

Shawurenine C (1a) and D (1b), a new pair of regioisomeric C19 -diterpenoid alkaloids, and five known C19 -diterpenoid alkaloids (2-6) were isolated from the aerial part of Delphinium shawurense W. T. Wang. The chemical structures of new compounds were established based on spectroscopic analyses: HR-ESI-MS, and 1D, 2D NMR spectroscopic data. The anti-inflammatory and cytotoxic activities of these diterpenoid alkaloids were also evaluated.

Diterpenoid alkaloids from Delphinium trichophorum.

Three new hetisine type C20-diterpenoid alkaloids, named as trichophorines A-C (1-3), were isolated from Delphinium trichophorum, together with nine known alkaloids (4-12). Their structures were elucidated on the basis of spectroscopic data (1D, 2D NMR, single-crystal X-ray, and HR-ESI-MS). All compounds were evaluated for the inhibitory activities against LPS induced NO production in RAW 264.7 macrophage cells, and none of them showed considerable inhibitory activity.

Polysubstituted Cyclopentene Benzamides and Dianthramide Alkaloids from Delphinium anthriscifolium Hance.

Thirteen new benzamide alkaloids, delphiniumines A-M (1-13), together with one known analogue (14), were isolated from Delphinium anthriscifolium Hance. All of the structures were determined by spectroscopic and spectrometric analyses. Absolute configuration for 1 was established using experimental and calculated ECD data, as well as by X-ray crystallography analysis. Compound 1 possesses a previously undescribed polysubstituted cyclopentene carbon framework. Compound 2 was isolated as an artifact from 1 during the extraction process. Compound 7 is glycosylated with a ß-D-glucose unit. Compound 13 bears a chlorine substituent. At a concentration of 10 µM, compounds 6, 8, and 10-12 suppressed LPS-induced NO production in RAW264.7 cells with inhibition rates ranging from 40.3% to 78.8%.

Three New Compounds from Delphinium kamaonense Hunth and Their in†Vitro Cytotoxic and Potential Antioxidant Activities.

A new amide (1), two new phenylpropanoid derivatives (2, 3), along with three new natural products, including three nitrogen chirality compounds, N-(3-methoxy-1,3-dioxopropyl)-D-phenylalanine methyl ester (4), N-(3-methoxy-1,3-dioxopropyl)-L-phenylalanine methyl ester (5), and N-acetyl-L-phenylalanine methyl ester (6), as well as dimethyl (2R,3R)-2-hydroxy-3-(((E)-3-(4-hydroxyphenyl)acryloyl)oxy)succinate (7) and dimethyl (S,E)-2-((3-(4-hydroxy-3-methoxyphenyl)acryloyl)oxy)succinate (8) were isolated from Delphinium kamaonense Hunth. Their structures were elucidated by extensive analysis of 1D and 2D NMR, and HR-ESI-MS experiments, and the absolute configurations were determined by comparative analysis of specific optical rotation. Compound 1 exhibited a moderate cytotoxicity effect against Hep-3B cancer cell lines (IC50 41.39±0.13 µM) and an excellent antioxidant activity (IC50 0.527±0.06 µM in ABTS assay, and 1.235±0.09 µM in DPPH assay, respectively), which was superior to vitamin C in ABTS (IC50 1.670±0.07 µM) and DPPH (IC50 19.10±0.40 µM) methods.

In Vitro and In Silico Investigation of Diterpenoid Alkaloids Isolated from Delphinium chitralense.

This study reports the isolation of three new C20 diterpenoid alkaloids, Chitralinine A-C (1-3) from the aerial parts of Delphinium chitralense. Their structures were established on the basis of latest spectral techniques and single crystal X-rays crystallographic studies of chitralinine A described basic skeleton of these compounds. All the isolated Compounds (1-3) showed strong, competitive type inhibition against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) in comparison to standard allanzanthane and galanthamine however, chitralinine-C remained the most potent with IC50 value of 11.64 ± 0.08 µM against AChE, and 24.31 ± 0.33 µM against BChE, respectively. The molecular docking reflected a binding free energy of -16.400 K Cal-mol-1 for chitralinine-C, having strong interactions with active site residues, TYR334, ASP72, SER122, and SER200. The overall findings suggest that these new diterpenoid alkaloids could serve as lead drugs against dementia-related diseases including Alzheimer's disease.

Diterpenoid Alkaloids Isolated from Delphinium brunonianum and Their Inhibitory Effects on Hepatocytes Lipid Accumulation.

This research aimed to excavate compounds with activity reducing hepatocytes lipid accumulation from Delphinium brunonianum. Four novel diterpenoid alkaloids, brunodelphinine B-E, were isolated from D. brunonianum together with eleven known diterpenoid alkaloids through a phytochemical investigation. Their structures were elucidated by comprehensive spectroscopy methods including HR-ESI-MS, NMR, IR, UV, CD, and single-crystal X-ray diffraction analysis. The inhibitory effects of a total of 15 diterpenoid alkaloids on hepatocytes lipid accumulation were evaluated using 0.5 mM FFA (oleate/palmitate 2:1 ratio) to induce buffalo rat liver (BRL) cells by measuring the levels of triglyceride (TG), total cholesterol (TC), alanine transaminase (ALT), aspartate transaminase (AST), and the staining of oil red O. The results show that five diterpenoid alkaloids-brunodelphinine E (4), delbruline (5), lycoctonine (7), delbrunine (8), and sharwuphinine A (12)-exhibited significant inhibitory effects on lipid accumulation in a dose-dependent manner and without cytotoxicity. Among them, sharwuphinine A (12) displayed the strongest inhibition of hepatocytes lipid accumulation in vitro. Our research increased the understanding on the chemical composition of D. brunonianum and provided experimental and theoretical evidence for the active ingredients screened from this herbal medicine in the treatment of the diseases related to lipid accumulation, such as non-alcoholic fatty liver disease and hyperlipidemia.

Alkaloids of Delphinium grandiflorum and their implication to H2O2-induced cardiomyocytes injury.

Three new diterpenoid alkaloids (1-3), and eight known alkaloids (4-11) were isolated from the aerial parts of Delphinium grandiflorum. Grandifline A (1) represents an unprecedented diterpenoid alkaloid ring system featuring a C-7NC17 hemiaminal moiety and a lactone fragment through the linkage of C-17OC19 unit. And we named this newly-discovered class of rearranged C19-diterpenoid alkaloid scaffold as grandiflodines (B-12). Grandifline B (2) is the first naturally-occurring 7,17-secolycoctonine diterpenoid alkaloid with a C-7OC17 unit forming a hemiacetal. Their structures were elucidated via spectroscopic data and single-crystal X-ray diffraction analysis. The protective effects of compounds 1-11 on H2O2-induced cardiomyocytes injury were assayed. And compounds 6 and 10 showed significant protective effects, with IC50 values of 1.881 ± 0.680 µM and 1.904 ± 0.750 µM, respectively. Further, compound 6 could reduce oxidative damage by inhibiting cell death via the AMPK/AKT/mTOR signaling pathway in H2O2-induced H9C2 cells.

In vitro anti-Acanthamoeba activity of flavonoid glycosides isolated from Delphinium gracile, D. staphisagria, Consolida oliveriana and Aconitum napellus.

Acanthamoeba spp. are widely distributed in the environment and cause serious infections in humans. Treatment of Acanthamoeba infections is very challenging and not always effective which requires the development of more efficient drugs against Acanthamoeba spp. The purpose of the present study was to test medicinal plants that may be useful in the treatment of Acanthamoeba spp. Here we evaluated the trophozoital and cysticidal activity of 13 flavonoid glycosides isolated from Delphinium gracile, D. staphisagria, Consolida oliveriana and from Aconitum napellus subsp. Lusitanicum against the amoeba Acanthamoeba castellanii. AlamarBlue Assay Reagent® was used to determine the activity against trophozoites of A. castellanii, and cytotoxic using Vero cells. Cysticidal activity was assessed on treated cysts by light microscopy using a Neubauer chamber to quantify cysts and trophozoites. Flavonoids 1, 2, 3 and 4 showed higher trophozoital activity and selectivity indexes than the reference drug chlorhexidine digluconate. In addition, flavonoid 2 showed 100% cysticidal activity at a concentration of 50 µm, lower than those of the reference drug and flavonoid 3 (100 µm). These results suggest that flavonoids 2 and 3 might be used for the development of novel therapeutic approaches against Acanthamoeba infections after satisfactory in vivo evaluations.

Antifungal Activity of New Diterpenoid Alkaloids Isolated by Different Chromatographic Methods from Delphinium peregrinum L. var. eriocarpum Boiss.

This paper aimed to investigate the potential antifungal influences of new alkaloids from Delphinium peregrinum L. var. eriocarpum Boiss. New Diterpenoid alkaloids Delcarpum (1), Hydrodavisine (4) and known alkaloids Peregrine (2), Delphitisine (3) were isolated by different chromatographic methods from the aerial parts of D. Peregrinum eriocarpum Boiss, which grows in Syria. The structures of alkaloids were proposed based on 1D NMR spectroscopy 1H-NMR, 13C-NMR, DEPT-135, DEPT-90, 2D NMR spectroscopy DQF-COSY, HMQC, EI-Ms mass spectrum, and IR spectroscopic measurements. The antifungal activity of the isolated alkaloids was evaluated against different dermatophyte fungal isolates compared with fluconazole. In the case of Peregrine (2) the minimum inhibitory concentrations(MICs) recorded 128-256, 32-64, and 32 for Epidermophyton floccosum, Microsporum canis, and Trichophyton rubrum, respectively, compared to 32-64, 16, and 32 µg/mL in the case of fluconazole, respectively. The MICs recorded on application of the four alkaloids mixture were 64, 32, and 16 in the case of E. floccosum, M. canis, and T. rubrum, respectively, which were significantly lower than that measured for each of the individual alkaloid and were compatible for fluconazole. In conclusion, MICs of the tested alkaloids showed a variable potential effect on the investigated fungal isolates. Peregrine (2) was the most effective alkaloid, however, the application of the mixture of alkaloids induced significant synergistic activity that was more pronounced than the application of individual ones.

Phytochemical analysis and reappraisal of diuretic activity of Delphinium brunonianum Royle and its mode of action in experimental rats.

The aim of this study was the evaluation of diuretic potential of Delphinium brunonianum. Acute diuretic effect in rats was evaluated 8 h after administration of various doses of crude extract, fractions and hydrochlorthiazide. While, prolonged effect of butanolic fraction was assessed after 7days of oral administration in rats. Thereafter, involvement of different pathways in diuretic activity was also appraised. Furthermore, polyphenolic contents in butanolic fraction were assessed using HPLC/UV-VIS technique. All doses of extract and fractions induced a prominent increase in urine and Na+ excretion with no effect on excretion of K+. Prior administration of indomethacin and atropine considerably avoided the diuretic effect of butanolic fraction. Regarding the quantitative chemical analysis the polyphenolic contents were recorded as 28.78 µg/mg. Thus results of present investigation suggested that Delphinium brunonianum possess remarkable diuretic potential.

Norditerpenoid alkaloids of Delphinium denudatum as cholinesterase inhibitors.

Three new norditerpenoids alkaloids, 1ß-hydroxy,14ß-acetyl condelphine (1), jadwarine-A (2), jadwarine-B (3) along with two known alkaloids isotalatizidine hydrate (4) and dihydropentagynine (5) were isolated from medicinal plant Delphinium denudatum. The structures of natural products 1-5 were established on the basis of HR-EIMS, 1H and 13C NMR (1D & 2D) spectroscopic data as well as by comparison from literature data. The structures of compound 1 and 4 were also confirmed by single crystal X-ray diffraction studies. In-vitro AChE and BChE enzyme inhibitory activities of compounds 1-5 and molecular docking studies were performed to investigate the possible molecular inhibitory mechanism of the isolated natural products. Compound 2, 4 and 5 showed competitive inhibitory effects by inhibiting AChE and BChE, respectively, while 1 and 3 showed non-competitive inhibition. This work is the first report that provides a supporting evidence about the use of constituents of Delphinium denudatum in cerebral dementia and Alzheimer diseases.

C18-Diterpenoid alkaloids from Delphinium anthriscifolium var. majus.

Five new C18-diterpenoid alkaloids, anthriscifoltines C-G (1-5), along with four known diterpenoid alkaloids anthriscifolcines C-F (6-9), were isolated from the extract of Delphinium anthriscifolium var. majus. Their structures were elucidated by extensive spectroscopic analyses (including 1D-, 2D-NMR, and HR-ESI-MS). Compounds 1-5 were also evaluated for their cytotoxic activity against MCF-7, HepG2, and H460 human cancer cell lines.

Diterpenoid Alkaloids from Delphinium ajacis and Their Anti-RSV Activities.

Five new diterpenoid alkaloids, ajacisines A-E (1-5), were isolated from Delphinium ajacis, along with seven known alkaloids (6-12). On the basis of their spectral data (IR, UV, HR-ESI-MS, 1D and 2D NMR) and chemical properties, the structures of compounds 1-12 were identified. All isolated compounds were evaluated for their in vitro antiviral activities against respiratory syncytial virus, and compounds 3-5 and 8 exhibited moderate to weak effects with IC50 values of 75.2 ± 1.1, 35.1 ± 0.6, 10.1 ± 0.3, and 50.2 ± 0.5 µM, respectively.

Five New C19 -Diterpenoid Alkaloids from Delphinium tianshanicum W.T.Wang.

Five new diterpenoid alkaloids, tianshanitines A-E (1 - 5), along with ten known compounds (6 - 15), were isolated from the EtOH extracts of the whole plant of Delphinium tianshanicum W.T.Wang. Their structures were determined based on extensive spectroscopic analyses, including 1D- and 2D-NMR, HR-ESI-MS, and the structure of tianshanitine C (3) was confirmed by X-ray diffraction analysis. Tianshanitine A (1) is the first example of natural diterpenoid alkaloid containing a benzoyl group at C(1) position. Tianshanitine B (2) is a rare natural diterpenoid alkaloid bearing a OH group at C(16) position. Compounds 1 - 5, 6, 8, 10, 12 and 14 were evaluated for cytotoxicity against HCT116, MCF-7 and HepG2 human cancer cell lines.

Isolation, crystal structure determination and cholinesterase inhibitory potential of isotalatizidine hydrate from Delphinium denudatum.

CONTEXT: Delphinium denudatum Wall (Ranunculaceae) is a rich source of diterpenoid alkaloids and is widely used for the treatment of various neurological disorders such as epilepsy, sciatica and Alzheimer's disease. OBJECTIVE: The present study describes crystal structure determination and cholinesterase inhibitory potential of isotalatazidine hydrate isolated from the aerial part of Delphinium denudatum. MATERIALS AND METHODS: Phytochemical investigation of Delphinium denudatum resulted in the isolation of isotalatazidine hydrate in crystalline form. The molecular structure of the isolated compound was established by X-ray diffraction. The structural data (bond length and angles) of the compound were calculated by Density Functional Theory (DFT) using B3LYP/6-31 + G (p) basis set. The cholinesterase inhibitory potential of the isolated natural product was determined at various concentrations (62.5, 125, 250, 500 and 1000 µg/mL) followed by molecular docking to investigate the possible inhibitory mechanism of isotalatazidine hydrate. RESULTS: The compound crystallized in hexagonal unit cell with space group P65. Some other electronic properties such as energies associated with HOMO-LUMO, band gaps, global hardness, global electrophilicity, electron affinity and ionization potential were also calculated by means of B3LYP/6-31 + G (p) basis set. The compound showed competitive type inhibition of both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with IC50 values of 12.13 µM and 21.41 µM, respectively. DISCUSSION AND CONCLUSION: These results suggest that isotalatazidine hydrate is a potent dual cholinesterase inhibitor and can be used as a target drug in Alzheimer diseases. This is first report indicating isotalatazidine hydrate with anticholinesterase potential.

p-Hydroxybenzoyl-glucose is a zwitter donor for the biosynthesis of 7-polyacylated anthocyanin in Delphinium.

The blue color of delphinium (Delphinium grandiflorum) flowers is produced by two 7-polyacylated anthocyanins, violdelphin and cyanodelphin. Violdelphin is derived from the chromophore delphinidin that has been modified at the 7-position by Glc and p-hydroxybenzoic acid (pHBA) molecules. Modification of violdelphin by linear conjugation of Glc and pHBA molecules to a Glc moiety at the 7-position produces cyanodelphin. We recently showed that anthocyanin 7-O-glucosylation in delphinium is catalyzed by the acyl-Glc-dependent anthocyanin glucosyltransferase (AAGT). Here, we sought to answer the question of which enzyme activities are necessary for catalyzing the transfer of Glc and pHBA moieties to 7-glucosylated anthocyanin. We found that these transfers were catalyzed by enzymes that use p-hydroxybenzoyl-Glc (pHBG) as a bifunctional acyl and glucosyl donor. In addition, we determined that violdelphin is synthesized via step-by-step enzymatic reactions catalyzed by two enzymes that use pHBG as an acyl or glucosyl donor. We also isolated a cDNA encoding a protein that has the potential for p-hydroxybenzoylation activity and two AAGT cDNAs that encode a protein capable of adding Glc to delphinidin 3-O-rutinoside-7-O-(6-O-[p-hydroxybenzoyl]-glucoside) to form violdelphin.

Norditerpenoid alkaloids from Delphinium anthriscifolium.

Two new norditerpenoid alkaloids with lycoctonine skeleton, anthriscifolcones A (1) and B (2), were isolated from the whole plant of Delphinium anthriscifolium var. Majus by extensive column chromatography. Their structures were established by IR, MS, (1)H NMR, (13)C NMR, and 2D NMR methods (including HSQC, (1)H-(1)H COSY, HMBC, and NOESY experiments).