The ethanol extract of Rhizoctonia rhizome was discovered to have substantial nematicidal action against two nematodes, namely the southern root-knot nematode and the pine wood nematode, during the screening process of novel agrochemicals derived from traditional Chinese medicinal ingredients. Columbianetin, Falcarindiol, Falcarinol, and Isoimperatorin were the four components of the ethanol extract that were separated based on bioactivity-guided fractionation. Isomperatorin's LC50 value against the pine wood nematode is 21.83 μg/mL. While columbianetin was just twice as harmful as the dark treatment, falcarindiol, falcarinol, and isoimperatorin were nearly five times more poisonous to Meloidogyne incognita after being exposed to a 15-minute UV light therapy. It has been demonstrated that isoimperatorin exhibits insecticidal activity against a range of insects, including cabbage aphids (Brevicoryne bassicae) [2]. The active component of the extract from Angelica dahurica dahurica (AD) included isoimperatorin [3]. An internal standard (IS) that is frequently utilized is isoimperatorin [4].

Metabolism / Metabolites
This study utilized a highly active, recyclable nanobioreactor prepared by immobilizing rat liver microsomes on magnetic nanoparticles (LMMNPs) to investigate the metabolism of Angelica dahurica extract. Five metabolites were detected in the incubation solution of the extract and LMMNPs, identified by HPLC-MS as trans-isoprene hydroxylate (M1), cis-isoprene hydroxylate (M2), isoprene epoxide (M3), trans-isoprene hydroxylate (M1'), and cis-isoprene hydroxylate (presumably M2'). Compared with the metabolism of isoprene and isoprene, these five metabolites were found to be derived from the transformation of these two main compounds present in the plant. Since there are currently no reported studies on the metabolism of isoimperatorin by the hepatic microsomal enzyme system, this study used preparative high-performance liquid chromatography (HPLC) to separate its metabolites (M1' and M3'), and identified their structures by (1) 1H nuclear magnetic resonance spectroscopy (H-NMR) and (2) mass spectrometry (MS). The results showed that M3' is an isoimperatorin epoxide, which is a novel compound in terms of its chemical structure. Interestingly, however, M3' was not detected in the metabolites of the whole plant extract. In addition, a study using known chemical inhibitors on isoisoprene family isozymes showed that CYP1A2 is involved in the metabolism of isoprenone and isoprenone, while CYP3A4 is involved only in the metabolism of isoprenone. Biotransformation studies of furanocoumarin isoisoprene (1) and isoprene (3) showed that compound 1 was metabolized by Glomerella cingulata to the corresponding reducing acid 6,7-furan-5-isopreneoxyhydrocoumaric acid (2), and compound 3 was converted by Glomerella cingulata to the dealkylating metabolite flavinol (4), with yields of 83% and 81%, respectively. The structure of the new compound 2 was determined based on spectral data. The inhibitory activities of metabolites 2 and 4 on β-secretase (BACE1) were tested in vitro. The results showed that metabolite 2 had a slight inhibitory effect on β-secretase activity, with an IC50 value of 185.6 ± 6.8 μM. The activity of metabolite 4 was lower than that of compounds 1-3. In addition, methyl ester (2Me), methyl ether (2a), and methyl ester and methyl ether (2aMe) of compound 2 were synthesized, and their ability to inhibit β-secretase was investigated. Compound 2aMe exhibited the best β-secretase inhibitory activity, with an IC50 value of 16.2 ± 1.2 μM, and 2aMe showed a competitive inhibition mode against β-secretase, with a Ki value of 11.3 ± 2.8 μM. Paraoxygenase (PON1) is a key enzyme in organophosphate metabolism. PON1 can inactivate certain organophosphates through hydrolysis. PON1 can hydrolyze active metabolites in various organophosphate pesticides and nerve agents (such as soman, sarin, and VX). The polymorphism of PON1 leads to differences in the enzyme activity level and catalytic efficiency of this esterase, suggesting that different individuals may be more susceptible to the toxicity of organophosphates.

Toxicity Summary
Identification and Uses: Isoimperatorin is a solid. It is found in traditional Chinese medicine tablets. It is used as a laboratory chemical and raw material for substance manufacturing. Human Studies: Coumarin compounds from A. dahurica, including isoimperatorin, significantly inhibit melatonin metabolism both in vivo and in vitro. Isoimperatorin inactivates cytochrome P450 A2 and 2B6. Animal Studies: Isoimperatorin exhibits photostimulatory effects in mice. Oral administration of isoimperatorin at a dose of 40 mg/kg to mice altered serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase activity, and/or albumin levels, indicating hepatotoxicity. Isoimperatorin inhibits platelet-derived growth factor-stimulated proliferation of bovine brain microvascular endothelial cells. Isoprene inhibits the activation of carcinogens by cytochrome P450 1B1. Ecotoxicity studies have shown that furanocoumarin compounds, such as isoisoprene and isoisoprene, accumulated in the old branches of Pituranthos triradiatus provide natural protection against grazing. Only hyraxes (Procavia capensis syriaca) that have ingested the old branches and been exposed to sunlight develop photosensitivity symptoms. Isoisoprene is an inhibitor of cholinesterase or acetylcholinesterase (AChE). Cholinesterase inhibitors (or "anticholinesterases") inhibit the activity of acetylcholinesterase. Because acetylcholinesterase has important physiological functions, chemicals that interfere with its activity are potent neurotoxins; even low doses can cause excessive salivation and lacrimation, followed by muscle spasms and ultimately death. Neurotoxins and substances in many pesticides have been shown to exert their effects by binding to serine residues at the active site of acetylcholinesterase, thereby completely inhibiting the enzyme's activity. Acetylcholinesterase is responsible for breaking down the neurotransmitter acetylcholine, which is released at the neuromuscular junction, causing muscle or organ relaxation. Inhibition of acetylcholinesterase results in the accumulation and sustained action of acetylcholine, leading to continuous nerve impulse transmission and an inability to stop muscle contraction. The most common acetylcholinesterase inhibitors are phosphorus-containing compounds designed to bind to the enzyme's active site. Their structure requires a phosphorus atom with two lipophilic groups, a leaving group (e.g., a halide or thiocyanate), and a terminal oxygen atom. Many furanocoumarins act based on their ability to form photoadducts with DNA and other cellular components such as RNA, proteins, and membrane proteins, such as phospholipases A2 and C, calcium-dependent and cAMP-dependent protein kinases, and epidermal growth factor. Furanocoumarins can insert between DNA base pairs and form cycloadducts upon UVA irradiation (L579).

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Interactions
Background and Purpose: Herbs are widely used as food and medicine and participate in many physiological and pathological processes.
Melatonin is a human hormone synthesized and secreted by the pineal gland, possessing a variety of biological functions. This study evaluated the potential effects of components extracted from common herbs on melatonin metabolism in humans. Methods: This study employed in vivo pharmacokinetic studies (including 12 healthy subjects), in vitro human liver microsome (HLM) and recombinant human cytochrome P450 (CYP) isoenzyme incubation experiments, and computational quantitative structure-activity relationship (QSAR) model analysis based on comparative molecular field analysis and comparative molecular similarity index analysis to explore these interactions. Main Results: After systematic screening of 66 commonly used herbs, Angelica dahurica was found to have the strongest inhibitory effect on melatonin metabolism in vitro. In vivo pharmacokinetic studies showed that Angelica dahurica inhibited melatonin metabolism, increasing the AUC and Cmax of melatonin in human subjects by approximately 12-fold and 4-fold, respectively. Coumarin compounds from Hedyotis diffusa (including isohexenoside, isohexenoside, chlorophyll, 5-methoxypsoralen, and 8-methoxypsoralen) significantly inhibited melatonin metabolism by inhibiting CYP1A2, 1A1, and 1B1 enzymes in human liver microsomes (HLM), with Ki values of 14.5 nM, 38.8 nM, 6.34 nM, 5.34 nM, and 18 nM, respectively. A quantitative structure-activity relationship (QSAR) model was established, which can predict the potential risk of coumarin compounds inhibiting melatonin metabolism in vivo. Conclusion and significance: Coumarin compounds from Hedyotis diffusa can inhibit melatonin metabolism both in vitro and in vivo. Our findings provide important guidance for the clinical application of melatonin. This study aimed to investigate the antigenotoxic effects of a series of natural furanocoumarins (NOFs), including isoimperatorin, imperatorin, (+)-oxoimperatorin, (+)-angelicin, and (+)-angelicine, on genotoxic metabolites induced by the carcinogens [furanofuranoamide and N-methyl-N'-nitro-N-nitrosoguanidine] and the pro-carcinogens 2-[2-(acetamido)-4-amino-5-methoxyphenyl]-5-amino-7-bromo-4-chloro-2H-benzotriazole (PBTA-4) and 2-amino-3,4-dimethyl-3H-imidazo[4,5-f]quinoline (MeIQ)]. These genotoxic metabolites were produced by rat S9 or rat and human recombinant cytochrome catalysis. P450 (CYP) 1A was detected using a UMU assay based on the SOS reaction. Five distinct NOFs identified in the human diet significantly inhibited procarcinogen-induced umuC expression without being affected by the carcinogens themselves. Notably, isopentenone and (+)-angelicin effectively inhibited the metabolic activation of PBTA-4 and MeIQ into genotoxic metabolites, respectively, catalyzed by rat and human CYP1A1 or rat and human CYP1A2. Furthermore, to elucidate the mechanism by which these NOFs exert their anti-genotoxic effects against procarcinogens, the effects of NOFs on the activity of 7-ethoxyhalothrin-O-deethylase (EROD), an enzyme associated with rat and human CYP1A1 or rat and human CYP1A2, were investigated. The inhibitory effect of some NOFs on EROD activity (IC50 values of 0.23–20.64 μM) was confirmed to be due to their potent inhibition of CYP1A1 and CYP1A2-dependent monooxygenases. Furthermore, the inhibitory mechanisms of NOFs on human CYP1A1 and CYP1A2 were analyzed using Dixon and Cornish-Bowden plots. Inhibition kinetics studies showed that these compounds inhibit human CYP1A1 and CYP1A2 through a variety of mechanisms, not a single one. In addition, two-stage incubation experiments indicated that, except for isopentenone, the inhibitory effect of NOFs on human CYP1A1 depends on a specific mechanism, while the inhibitory effect on human CYP1A2 is direct. These data suggest that some NOFs exposed to in the human diet may affect the metabolic activation of carcinogenic precursors by inhibiting CYP1A1 and CYP1A2 enzymes.

[1]. Acetylcholinesterase inhibitors from the roots of Angelica dahurica. Arch Pharm Res. 2002 Dec;25(6):856-9.

[2]. Identification of Nematicidal Constituents of Notopterygium incisum Rhizomes against Bursaphelenchus xylophilus and Meloidogyne incognita. Molecules. 2016 Sep 23;21(10). pii: E1276.

[3]. Angelica dahurica Extracts Improve Glucose Tolerance through the Activation of GPR119. PLoS One. 2016 Jul 8;11(7):e0158796.

[4]. The pharmacokinetics, bioavailability and excretion of bergapten after oral and intravenous administration in rats using high performance liquid chromatography with fluorescence detection. Chem Cent J. 2016 Oct 14;10:62.

Isoimperatorin is a psoralen compound with a structure in which psoralen is replaced by an isopentenyl group at the 5-position. It was isolated from Angelica dahurica and Angelica koreana and is an acetylcholinesterase inhibitor. It is both a metabolite and an EC 3.1.1.7 (acetylcholinesterase) inhibitor. Isoimperatorin has also been reported in Salvia miltiorrhiza, Angelica gigas, and other organisms with relevant data. Isoimperatorin is a tumor necrosis factor antagonist and can be isolated from the roots of Phyllanthus emblica or Poncirus trifoliata Raf (L579) . Furanocoumarins possess phototoxicity and photocarcinogenicity. They can intercalate into DNA and photochemically induce mutations. Furanocoumarins are phytoalexins widely found in various vegetables and fruits, especially citrus fruits. While the levels of furanocoumarins in our diet are generally far below the levels that cause significant acute phototoxicity, they do indeed cause pharmacologically significant drug interactions. Some furanocoumarins are particularly active against cytochrome P450 enzymes. For example, in humans, bergamot and dihydroxybergamot are the culprits of the "grapefruit juice effect," in which these furanocoumarins affect the metabolism of certain drugs.
See also: Angelica sinensis root (partial).

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Therapeutic Uses
/EXPL THER/ Background: Prangos ferulacea (L.) Lindl. (Apiaceae) is a perennial plant distributed in the Middle East and commonly used as an antispasmodic and anti-inflammatory agent. It is rich in coumarins. Objective: To purify several coumarins from P. ferulacea and screen their cytotoxic and antiherpesvirus activities. Materials and Methods: Acetone extracts from the roots of P. ferulacea were subjected to multiple chromatographic separations to obtain pure coumarin compounds (1-8). The antiherpesvirus activity of compounds 1-7 against fusion Vero cell monolayers infected with 25 PFU/plaque-forming units HSV1 was evaluated at concentrations of 2.5, 5, and 10 μg/mL. The cytotoxicity of compounds 1 and 2 against the A2780S cell line was assessed using the MTT assay. Cells were exposed to a series of concentrations of coumarin compounds (0.01–2.5 mM, 37 °C, 72 h). Results: Compounds 1-8 were identified as parsnipin, isopseripin, oxyparseripin, psoralen, oxyparseripin hydrate, gosferol, oxyparseripin methyl ester, and pranylphenol. This is the first report of the presence of compounds 4 and 7 in this plant. Compound 1 showed a cell viability of 9.41% ± 2.4 in A2780S cells at a concentration of 2.5 mM (IC50 = 0.38 mM). Compound 2 showed a cell viability of 46.86% ± 5.5 at a concentration of 2.5 mM, with an IC50 of 1.1 mM. Discussion and Conclusion: Compound 1 exhibits cytotoxicity against the A2780S cell line. Compound 2 is a cyclooxygenase-2 inhibitor, and the A2780S cell line does not express COX-2, which may explain why this compound is not toxic to this cell line. None of the tested compounds showed anti-HSV activity at non-toxic concentrations. Angelica dahuricae contains coumarin, which may affect the activity of cytochrome P450 enzymes (CYP450), and therefore is often used in combination with the CYP450 substrate tetramethylpyrazine for the clinical treatment of migraine. However, the existence of a pharmacokinetic synergistic effect between Angelica dahurica and tetramethylpyrazine remains unclear. This study found that the total coumarin extract (TCE) of Angelica dahurica (50 mg/kg, orally for three consecutive days) enhanced the anti-migraine activity of tetramethylpyrazine, manifested by reducing scratching frequency, plasma calcitonin gene-related peptide (CGRP) levels, and serum nitric oxide levels in rats, and increasing plasma endothelin levels (p < 0.05). Furthermore, pharmacokinetic studies showed that trichloroethylene (TCE) increased the area under the concentration-time curve of tetramethylpyrazine and prolonged its mean residence time in rats (p < 0.05). Furthermore, in human liver microsomes, the IC50 values of TCE, isosaxifen, and isosaxifen inhibiting tetramethylpyrazine metabolism were 5.0 ± 1.02, 1.35 ± 0.46, and 4.81 ± 1.14 μg/mL, respectively; in rat liver microsomes, the IC50 values were 13.69 ± 1.11, 1.19 ± 1.09, and 1.69 ± 1.17 μg/mL, respectively. In addition, isosaxifen and isosaxifen are CYP450 enzyme inhibitors, with IC50 values less than 10 μM for CYP1A2, 2C9, 2D6, and 3A4. Therefore, this study concludes that Angelica dahurica can inhibit tetramethylpyrazine metabolism by interfering with CYP450 enzymes, thereby increasing the plasma concentration of tetramethylpyrazine and enhancing its pharmacological effects. This may be one of the mechanisms by which Angelica dahurica and tetramethylpyrazine produce a synergistic effect in the treatment of migraine. Previous studies have shown that isoimperatorin (IO), a furanocoumarin isolated from various medicinal plants, possesses antimycobacterial activity against Mycobacterium tuberculosis strain H37Rv (ATCC 27294). This study confirms that IO exhibits antimycobacterial activity against two drug-sensitive strains and six drug-resistant strains, with minimum inhibitory concentrations (MICs) of 50-100 μg/mL and 100-200 μg/mL, respectively. IO, rifampin (RMP), isoniazid (INH), and ethambutol (EMB) showed synergistic antimycobacterial activity against the six drug-resistant strains, with partial inhibitory concentration indices (FICIs) of 0.133-0.472, 0.123-0.475, and 0.124-0.25, respectively. Combinations of IO/RMP, IO/INH, and IO/EMB showed synergistic effects or no interaction against two drug-sensitive strains and the standard strain ATCC 27294. The synergistic effect of the combination therapy was superior against drug-sensitive strains. No antagonistic effects were observed against any of the tested strains. IO exhibited relatively low cytotoxicity against Vero cells. Our results suggest that IO may serve as an effective template for future antimycobacterial drug development. Significance and Impact: ...The results indicate that isoprenone (IO) has weak antimycobacterial activity; however, when used in combination with first-line antimycobacterial drugs, IO shows some efficacy against Mycobacterium tuberculosis, warranting further development as a lead compound for novel antimycobacterial therapeutics.
/EXPL THER/ Typically, chemopreventive agents either induce phase II detoxification enzymes or inhibit cytochrome P450 enzymes (CYPs), which are essential for carcinogen metabolism. In this study, we isolated a coumarin compound, isoprenone, from Poncirus trifoliata Raf. and investigated its protective effect against aflatoxin B1 (AFB1)-induced H4IIE cytotoxicity. Isoprenone (>0.3 μM) significantly inhibited the cytotoxic effect of AFB1. CDNB (1-chloro-2,4-dinitrophenyl; glutathione S-transferase (GST) subtype nonspecific) and NBD (7-chloro-4-nitrobenzo-2-oxa-1,3-diazole; GSTα type specific) assays showed that isoprenone (0.3–3 μM) increased GST activity in a concentration-dependent manner. Western blot analysis using subtype-specific antibodies confirmed that GSTα protein expression (but not GSTμ or GSTpi) was induced in isoprenone-treated cells. Reporter gene analysis and subcellular fractionation experiments using constructs containing antioxidant response elements (AREs) showed that isoprenone-induced GSTα expression was associated with Nrf2/ARE activation. Furthermore, ethoxylated halogen-O-deethylase activity assays indicated that isoprenone (2 μM) completely inhibited 3-methylchloroanthracene-induced CYP1A activity. These results suggest that isoprenone from Poncirus trifoliata Raf. has a significant hepatoprotective effect against aflatoxin B1 (AFB1), presumably through the induction of glutathione S-transferase α (GSTα) and direct inhibition of cytochrome P450 1A (CYP1A), suggesting that isoprenone should be considered a potential chemopreventive agent.
/EXPL THER/ Background: The roots of Ostericum koreanum (Maxim.) Kitagawa (Apiaceae) have traditionally been used as an analgesic and anti-ulcer agent. However, the anti-ulcer potential of isoprene isolated from Erycibe obtusifolia has not been investigated. Objective: To evaluate the anti-ulcer activity of isoprene isolated from the root of Erycibe obtusifolia. Materials and Methods: Isoprene was isolated from the ethyl acetate extract by repeated column chromatography to obtain cubic crystals, and its structure was verified by 1H NMR, 13C NMR, and high-resolution mass spectrometry (HRMS-FAB). The obtained crystals were analyzed by single-crystal X-ray diffraction. The cytotoxicity of isoprene to chondrocytes at different concentrations (0.0-737.74 μM, 24 hr) was determined by the MTT assay. In a Sprague-Dawley rat model, the in vivo anti-ulcer activity of isoprene (40 mg/kg) against ethanol, indomethacin, and pyloric ligation-induced ulcers was determined. In addition, the effect of isopentenone (0.0-737.74 μM, 24 hr) on type II collagen expression in chondrocytes was determined by Western blot. This study also performed in vitro urease inhibitory activity assays and molecular docking experiments using isopentenyl isopentenyl (0-80 μM). Results and Discussion: Compared with the standard drug thiourea (IC50 33.57 μM), isopentenyl isopentenyl showed significant inhibitory activity against urease (IC50 36.43 μM) without cytotoxicity. In ulcer models induced by ethanol, indomethacin, and pyloric ligation, isopentenyl...

C16H14O4

270.2800

270.089

482-45-1

Isoimperatorin-d6

68081

White to off-white solid powder

1.2±0.1 g/cm3

448.3±45.0 °C at 760 mmHg

109ºC

224.9±28.7 °C

0.0±1.1 mmHg at 25°C

1.606

3.88

0

4

3

20

436

0

IGWDEVSBEKYORK-UHFFFAOYSA-N

InChI=1S/C16H14O4/c1-10(2)5-7-19-16-11-3-4-15(17)20-14(11)9-13-12(16)6-8-18-13/h3-6,8-9H,7H2,1-2H3

4-(3-methylbut-2-enoxy)furo[3,2-g]chromen-7-one

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: This product requires protection from light (avoid light exposure) during transportation and storage.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Ethanol : ~8.33 mg/mL (~30.82 mM)
DMSO : ~2.5 mg/mL (~9.25 mM)

Solubility in Formulation 1: ≥ 0.83 mg/mL (3.07 mM) (saturation unknown) in 10% EtOH + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 8.3 mg/mL clear EtOH stock solution to 400 μL of PEG300 and mix evenly; then add 50 μL of Tween-80 to the above solution and mix evenly; then add 450 μL of normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 0.83 mg/mL (3.07 mM) (saturation unknown) in 10% EtOH + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 8.3 mg/mL clear EtOH stock solution to 900 μL of corn oil and mix well.

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 (Please use freshly prepared in vivo formulations for optimal results.)