Diterpenoid Compounds Isolated from Chloranthus oldhamii Solms Exert Anti-Inflammatory Effects by Inhibiting the IKK/NF-κB Pathway

Chloranthus oldhamii Solms (CO) is a folk medicine for treating infection and arthritis pain but its pharmacological activity and bioactive compounds remain mostly uncharacterized. In this study, the anti-inflammatory compounds of C. oldhamii were identified using an LPS-stimulated, NF-κB-responsive RAW 264.7 macrophage reporter line. Three diterpenoid compounds, 3α-hydroxy-ent-abieta-8,11,13-triene (CO-9), 3α, 7β-dihydroxy-ent-abieta-8,11,13-triene (CO-10), and decandrin B (CO-15) were found to inhibit NF-κB activity at nontoxic concentrations. Moreover, CO-9 and CO-10 suppressed the expression of IL-6 and TNF-α in LPS-stimulated RAW 264.7 cells. The inhibitory effect of CO-9 on TNF-α and IL-6 expression was further demonstrated using LPS-treated bone marrow-derived macrophages. Furthermore, CO-9, CO-10, and CO-15 suppressed LPS-triggered COX-2 expression and downstream PGE2 production in RAW 264.7 cells. CO-9 and CO-10 also reduced LPS-triggered iNOS expression and nitrogen oxide production in RAW 264.7 cells. The anti-inflammatory mechanism of the most effective compound, CO-9, was further investigated. CO-9 attenuated LPS-induced NF-κB activation by reducing the phosphorylation of IKKα/β (Ser176/180), IκBα (Ser32), and p65 (Ser534). Conversely, CO-9 did not affect the LPS-induced activation of MAPK signaling pathways. In summary, this study revealed new anti-inflammatory diterpenoid compounds from C. oldhamii and demonstrated that the IKK-mediated NK-κB pathway is the major target of these compounds.     

Antioxidant and Anti-Inflammatory Activities of Six Flavonoids from Smilax glabra Roxb

This study aimed to isolate, prepare and identify the main flavonoids from a standardized Smilax glabra flavonoids extract (SGF) using preparative HPLC, MS, ¹H NMR and ¹³C NMR, determine the contents of these flavonoids using UPLC, then compare their pharmacological activities in vitro. We obtained six flavonoids from SGF: astilbin (18.10%), neoastilbin (11.04%), isoastilbin (5.03%), neoisoastilbin (4.09%), engeletin (2.58%) and (−)-epicatechin (1.77%). The antioxidant activity of six flavonoids were evaluated by determining the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and 2,2′-Azinobis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS⁺) radical scavenging activity and ferric reducing antioxidant power (FRAP). In addition, the anti-inflammatory activity of six flavonoids were evaluated by determining the production of cytokines (IL-1β, IL-6), nitric oxide (NO) using enzyme linked immunosorbent assay and the NF-κB p65 expression using Western blotting in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. The results showed that (−)-epicatechin, astilbin, neoastilbin, isoastilbin and neoisoastilbin had strong antioxidant activities, not only in DPPH and ABTS⁺ radicals scavenging capacities, but in FRAP system. Furthermore, all the six flavonoids could significantly inhibit the secretion of IL-1β, IL-6, NO (p < 0.01) and the protein expression of NF-κB p-p65 (p < 0.01) in LPS-stimulated RAW264.7 cells. This study preliminarily verified the antioxidant and anti-inflammatory activities of six flavonoids in S. glabra.     

Iridal-Type Triterpenoids Displaying Human Neutrophil Elastase Inhibition and Anti-Inflammatory Effects from Belamcanda chinensis

The aim of this study is to explore anti-inflammatory phytochemicals from B. chinensis based on the inhibition of pro-inflammatory enzyme, human neutrophil elastase (HNE) and anti-inflammatory activities in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage. Three stereoisomers of iridal-type triterpenoids (1–3) were isolated from the roots of B. chinensis and their stereochemistries were completely identified by NOESY spectra. These compounds were confirmed as reversible noncompetitive inhibitors against HNE with IC₅₀ values of 6.8–27.0 µM. The binding affinity experiment proved that iridal-type triterpenoids had only a single binding site to the HNE enzyme. Among them, isoiridogermanal (1) and iridobelamal A (2) displayed significant anti-inflammatory effects by suppressing the expressions of pro-inflammatory cytokines, such as iNOS, IL-1β, and TNF-α through the NF-κB pathway in LPS-stimulated RAW264.7 cells. This is the first report that iridal-type triterpenoids are considered responsible phytochemicals for anti-inflammatory effects of B. chinensis.     

Immunomodulatory Responses of Two Synthetic Peptides against Salmonella Typhimurium Infection

In vitro assays of phagocytic activity showed that the peptide Pin2[G] stimulates phagocytosis in BMDM cells from 0.15 to 1.25 μg/mL, and in RAW 264.7 cells at 0.31 μg/mL. In the same way, the peptide FA1 induced phagocytosis in BMDM cells from 1.17 to 4.69 μg/mL and in RAW 264.7 cells at 150 μg/mL. Cytokine profiles of uninfected RAW 264.7 showed that Pin2[G] increased liberation TNF (from 1.25 to 10 μg/mL) and MCP-1 (10 μg/mL), and FA1 also increased the release of TNF (from 18.75 to 75 μg/mL) but did not increase the liberation of MCP-1. In RAW 264.7 macrophages infected with Salmonella enterica serovar Typhimurium, the expression of TNF increases with Pin2[G] (1.25–10 μg/mL) or FA1 (18.75–75 μg/mL). In these cells, FA1 also increases the expression of IL-12p70, IL-10 and IFN-γ when applied at concentrations of 37.5, 75 and 150 μg/mL, respectively. On the other hand, stimulation with 1.25 and 10 μg/mL of Pin2[G] promotes the expression of MCP-1 and IL-12p70, respectively. Finally, peptides treatment did not resolve murine gastric infection, but improves their physical condition. Cytokine profiles showed that FA1 reduces IFN-γ and MCP-1 but increases IL-10, while Pin2[G] reduces IFN-γ but increases the liberation of IL-6 and IL-12p70. This data suggests a promising activity of FA1 and Pin2[G] as immunomodulators of gastric infections in S. Typhimurium.     

Aurones and Flavonols from Coreopsis lanceolata L. Flowers and Their Anti-Oxidant,Pro-Inflammatory Inhibition Effects,and Recovery Effects on Alloxan-Induced Pancreatic Islets in Zebrafish

(1) Background: Many flavonoids have been reported to exhibit pharmacological activity; a preparatory study confirmed that Coreopsis lanceolata flowers (CLFs) contained high flavonoid structure content; (2) Methods: CLFs were extracted in aqueous methanol (MeOH:H₂O = 4:1) and fractionated into acetic ester (EtOAc), normal butanol (n-BuOH), and H₂O fractions. Repeated column chromatographies for two fractions led to the isolation of two aurones and two flavonols; (3) Results: Four flavonoids were identified based on a variety of spectroscopic data analyses to be leptosidin (1), leptosin (2), isoquercetin (3), and astragalin (4), respectively. This is the first report for isolation of 2–4 from CLFs. High-performance liquid chromatography (HPLC) analysis determined the content levels of compounds 1–4 in the MeOH extract to be 2.8 ± 0.3 mg/g (1), 17.9 ± 0.9 mg/g (2), 3.0 ± 0.2 mg/g (3), and 10.9 ± 0.9 mg/g (4), respectively. All isolated compounds showed radical scavenging activities and recovery activities in Caco-2, RAW264.7, PC-12, and HepG2 cells against reactive oxygen species. MeOH extract, EtOAc fraction, and 1–3 suppressed NO formation in LPS-stimulated RAW 264.7 cells and decreased iNOS and COX-2 expression. Furthermore, all compounds recovered the pancreatic islets damaged by alloxan treatment in zebrafish; (4) Conclusions: The outcome proposes 1–4 to serve as components of CLFs in standardizing anti-oxidant, pro-inflammatory inhibition, and potential anti-diabetic agents.     

Synthesis of Tyrosol and Hydroxytyrosol Glycofuranosides and Their Biochemical and Biological Activities in Cell-Free and Cellular Assays

Tyrosol (T) and hydroxytyrosol (HOT) and their glycosides are promising candidates for applications in functional food products or in complementary therapy. A series of phenylethanoid glycofuranosides (PEGFs) were synthesized to compare some of their biochemical and biological activities with T and HOT. The optimization of glycosylation promoted by environmentally benign basic zinc carbonate was performed to prepare HOT α-L-arabino-, β-D-apio-, and β-D-ribofuranosides. T and HOT β-D-fructofuranosides, prepared by enzymatic transfructosylation of T and HOT, were also included in the comparative study. The antioxidant capacity and DNA-protective potential of T, HOT, and PEGFs on plasmid DNA were determined using cell-free assays. The DNA-damaging potential of the studied compounds for human hepatoma HepG2 cells and their DNA-protective potential on HepG2 cells against hydrogen peroxide were evaluated using the comet assay. Experiments revealed a spectrum of different activities of the studied compounds. HOT and HOT β-D-fructofuranoside appear to be the best-performing scavengers and protectants of plasmid DNA and HepG2 cells. T and T β-D-fructofuranoside display almost zero or low scavenging/antioxidant activity and protective effects on plasmid DNA or HepG2 cells. The results imply that especially HOT β-D-fructofuranoside and β-D-apiofuranoside could be considered as prospective molecules for the subsequent design of supplements with potential in food and health protection.     

1,3,5-Triazine Nitrogen Mustards with Different Peptide Group as Innovative Candidates for AChE and BACE1 Inhibitors

A series of new analogs of nitrogen mustards (4a–4h) containing the 1,3,5-triazine ring substituted with dipeptide residue were synthesized and evaluated for the inhibition of both acetylcholinesterase (AChE) and β-secretase (BACE1) enzymes. The AChE inhibitory activity studies were carried out using Ellman’s colorimetric method, and the BACE1 inhibitory activity studies were carried out using fluorescence resonance energy transfer (FRET). All compounds displayed considerable AChE and BACE1 inhibition. The most active against both AChE and BACE1 enzymes were compounds A and 4a, with an inhibitory concentration of AChE IC₅₀ = 0.051 µM; 0.055 µM and BACE1 IC₅₀ = 9.00 µM; 11.09 µM, respectively.     

Diterpenoids Isolated from Podocarpus macrophyllus Inhibited the Inflammatory Mediators in LPS-Induced HT-29 and RAW 264.7 Cells

Species of Podocarpus are used traditionally in their native areas for the treatment of fevers, asthma, coughs, cholera, chest pain, arthritis, rheumatism, and sexually transmitted diseases. To identify natural products having efficacy against inflammatory bowel disease (IBD), we identified a new, 16-hydroxy-4β-carboxy-O-β-D-glucopyranosyl-19-nor-totarol (4) together with three known diterpenoids from P. macrophyllus. Furthermore, all the extracts, fractions, and isolates 1–4 were investigated for their anti-inflammatory effects by assessing the expression on nitric oxide (NO) production and proinflammatory cytokines in lipopolysaccharide (LPS)-stimulated RAW 264.7 and HT-29 cells. Among them, nagilactone B (2) exhibited a potent anti-inflammatory effect against NO production on RAW 264.7 cells; therefore, nagilactone B was further assessed for anti-inflammatory activity. Western blot analysis revealed that nagilactone B significantly decreased the expression of LPS-stimulated protein, inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, and phosphorylated extracellular regulated kinase (pERK)1/2. In addition, nagilactone B downregulated tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-8 levels in LPS-induced macrophages and colonic epithelial cells. To our best knowledge, this is the first report on the inhibitory effect of nagilactone B (pure state) and rakanmakilactone G against NO production in LPS-stimulated RAW 264.7 cells. Thus, diterpenoids isolated from P. macrophyllus could be employed as potential therapeutic phytochemicals for IBD.     

Synthesis and antitumor activity of benzimidazolyl-1,3,5-triazine and benzimidazolylpyrimidine derivatives

Triamino-substituted 1,3,5-triazine and pyrimidine derivatives were synthesized and tested for antitumor activities using some human cancer cell lines and murine leukemia cell lines. All the compounds having benzimidazolyl and morpholino groups as substituents on the 1,3,5-triazine ring showed antitumor activity. Pyrimidine derivatives having the same groups as substituents also showed antitumor activity. Among them, the compounds having 1-benzimidazolyl, morpholino and cis-2,3-dimethylmorpholino groups as substituents on the 1,3,5-triazine ring or pyrimidine ring exhibited the most potent antitumor activity, and these compounds exhibited no or very weak aromatase inhibitory activity. In contrast, the compounds having imidazolyl group instead of benzimidazolyl group as a substituent on the 1,3,5-triazine ring showed a potent aromatase inhibitory activity.     

Effect of 1-Carbaldehyde-3,4-dimethoxyxanthone on Prostate and HPV-18 Positive Cervical Cancer Cell Lines and on Human THP-1 Macrophages

Xanthone derivatives have shown promising antitumor properties, and 1-carbaldehyde-3,4-dimethoxyxanthone (1) has recently emerged as a potent tumor cell growth inhibitor. In this study, its effect was evaluated (MTT viability assay) against a new panel of cancer cells, namely cervical cancer (HeLa), androgen-sensitive (LNCaP) and androgen-independent (PC-3) prostate cancer, and nonsolid tumor derived cancer (Jurkat) cell lines. The effect of xanthone 1 on macrophage functions was also evaluated. The effect of xanthone 1-conditioned THP-1 human macrophage supernatants on the metabolic viability of cervical and prostate cancer cell lines was determined along with its interference with cytokine expression characteristic of M1 profile (IL-1 ≤ β; TNF-α) or M2 profile (IL-10; TGF-β) (PCR and ELISA). Nitric oxide (NO) production by murine RAW264.7 macrophages was quantified by Griess reaction. Xanthone 1 (20 μM) strongly inhibited the metabolic activity of the cell lines and was significantly more active against prostate cell lines compared to HeLa (p < 0.05). Jurkat was the cell most sensitive to the effect of xanthone 1. Compound 1-conditioned IL-4-stimulated THP-1 macrophage supernatants significantly (p < 0.05) inhibited the metabolic activity of HeLa, LNCaP, and PC-3. Xanthone 1 did not significantly affect the expression of cytokines by THP-1 macrophages. The inhibiting effect of compound 1 observed on the production of NO by RAW 264.7 macrophages was moderate. In conclusion, 1-carbaldehyde-3,4-dimethoxyxanthone (1) decreases the metabolic activity of cancer cells and seems to be able to modulate macrophage functions.     

Differential regulation of inducible nitric oxide synthase and cyclooxygenase-2 expression by superoxide dismutase in lipopolysaccharide stimulated RAW 264.7 cells

Inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) have been known to be involved in various pathophysiological processes such as inflammation. This study was performed to determine the regulatory function of superoxide dismutase (SOD) on the LPS-induced expression of iNOS, and COX-2 in RAW 264.7 cells. When a cell-permeable SOD, Tat-SOD, was added to the culture medium of RAW 264.7 cells, it rapidly entered the cells in a dose-dependent manner. Treatment of RAW 264.7 cells with Tat-SOD led to decrease in LPS-induced ROS generation. Pretreatment with Tat-SOD significantly inhibited LPS-induced expression of iNOS and NO production but had no effect on the expression of COX-2 and PGE₂ production in RAW 264.7 cells. Tat-SOD inhibited LPS-induced NF-κB DNA binding activity, IκBα degradation and activation of MAP kinases. These data suggest that SOD differentially regulate expression of iNOS and COX-2 in LPS-stimulated RAW 264.7 cells.     

Prunetin 4′-O-Phosphate,a Novel Compound,in RAW 264.7 Macrophages Exerts Anti-Inflammatory Activity via Suppression of MAP Kinases and the NFκB Pathway

Biorenovation, a microbial enzyme-assisted degradation process of precursor compounds, is an effective approach to unraveling the potential bioactive properties of the derived compounds. In this study, we obtained a new compound, prunetin 4′-O-phosphate (P4P), through the biorenovation of prunetin (PRN), and investigated its anti-inflammatory effects in lipopolysaccharide (LPS)-treated RAW 264.7 macrophage cells. The anti-inflammatory effect of P4P was evaluated by measuring the production of prostaglandin-E₂ (PGE₂), nitric oxide (NO), which is an inflammation-inducing factor, and related cytokines such as tumor necrosis factor-α (TNFα), interleukin-1β (IL1β), and interleukin-6 (IL6). The findings demonstrated that P4P was non-toxic to cells, and its inhibition of the secretion of NO—as well as pro-inflammatory cytokines—was concentration-dependent. A simultaneous reduction in the protein expression level of pro-inflammatory proteins such as cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) was observed. Moreover, the phosphorylation of mitogen-activated protein kinases (MAPKs) such as extracellular signal-regulated kinases (ERKs), c-Jun N-terminal kinase (JNK), p38 MAPK (p38), and nuclear factor kappa B (NFκB) was downregulated. To conclude, we report that biorenovation-based phosphorylation of PRN improved its anti-inflammatory activity. Cell-based in vitro assays further confirmed that P4P could be applied in the development of anti-inflammatory therapeutics.     

Synthesis and molecular structure of 2-methoxy-4-amino-6-dinitromethyl-1,3,5-triazines zwitterionic salts

Zwitterionic salts of 2-methoxy-4-amino-6-dinitromethyl-1,3,5-triazines were synthesized. The structure of the compounds and the site of nitrogen protonation in the 1,3,5-triazine ring were established based on IR and ¹H NMR spectra and on the data of X-ray diffraction analysis.     

Splenectomy improves liver fibrosis via tumor necrosis factor superfamily 14 (LIGHT) through the JNK/TGF-β1 signaling pathway

Splenectomy has been reported to improve liver fibrosis in patients with cirrhosis and hypersplenism. However, the mechanisms remain unclear. Tumor necrosis factor superfamily 14 (TNFSF14; also known as LIGHT) is highly expressed in the context of fibrosis and promotes disease progression in patients with fibrotic diseases such as pulmonary and skin fibrosis. Here, we determined whether splenectomy controls the production of LIGHT to improve liver fibrosis. Splenectomy reduced serum LIGHT levels in cirrhotic patients with hypersplenism and a ConA-induced liver fibrosis mouse model. Blocking LIGHT resulted in the downregulation of TGF-β1 in RAW264.7 cells. LIGHT treatment of RAW264.7 and JS1 cells in coculture regulated transforming growth factor-β1 (TGF-β1) expression through the activation of JNK signaling. Small interfering RNA-mediated silencing of lymphotoxin β receptor (LTβR) in macrophages resulted in pronounced decreases in the levels of fibrosis and αSMA in JS1 cells. These results indicated that LIGHT bound to LTβR and drove liver fibrosis in vitro. Blocking TGF-β1 abolished the effect of LIGHT in vitro. Furthermore, the administration of recombinant murine LIGHT protein-induced liver fibrosis with splenectomy, while blocking LIGHT without splenectomy improved liver fibrosis in vivo, revealing that the decrease in fibrosis following splenectomy was directly related to reduced levels of LIGHT. Thus, high levels of LIGHT derived from the spleen and hepatic macrophages activate JNK signaling and lead to increased TGF-β1 production in hepatic macrophages. Splenectomy attenuates liver fibrosis by decreasing the expression of LIGHT.Subject terms: Tumour-necrosis factors, Liver fibrosis, Hepatic stellate cells, Liver cirrhosis, Experimental models of disease     

Polyethylene glycol-based ultrasound-assisted extraction of magnolol and honokiol from Cortex Magnoliae Officinalis

In this study, a kind of green solvent named polyethylene glycol (PEG) was developed for the ultrasound-assisted extraction (UAE) of magnolol and honokiol from Cortex Magnoliae Officinalis. The effects of PEG molecular weight, PEG concentration, sample size, pH, ultrasonic power and extraction time on the extraction of magnolol and honokiol were investigated to optimise the extraction conditions. Under the optimal extraction conditions, the PEG-based UAE supplied higher extraction efficiencies of magnolol and honokiol than the ethanol-based UAE and traditional ethanol-reflux extraction. Furthermore, the correlation coefficient (R²), repeatability (relative standard deviation, n = 6) and recovery confirmed the validation of the proposed extraction method, which were 0.9993–0.9996, 3.1–4.6% and 92.3–106.8%, respectively.     

Trichilianones A-D,Novel Cyclopropane-Type Limonoids from Trichilia adolfi

The fractionation of an ethanol extract of the bark of Trichilia adolfi yielded four novel limonoids (trichilinones A-D, 1–4), with five fused rings and related to the hortiolide-type limonoids. Starting with an ε-lactone, which is α,β-unsaturated in trichilinones A and D (1 and 4), attached to a tetrahydrofuran ring that is connected to an unusual bicyclo [5.1.0] hexane system, joined with a cyclopentanone with a 3-furanyl substituent [(2-oxo)-furan-(5H)-3-yl in trichilinone D (4)], the four compounds isolated display a new 7/5/3/5/5 limonoid ring system. Their structures were established based on extensive analysis of NMR spectroscopic data. As the crude extract possessed anti-leishmanial properties, the compounds were assayed for cytotoxic and anti-parasitic activities in vitro in murine macrophages cells (Raw 264.7) and leishmania promastigotes (L. amazoniensis and L. braziliensis), respectively. The compounds showed moderate cytotoxicity (approximately 70 μg/mL), but are not responsible for the leishmanicidal effect of the extract.     

Purification,Structural Characterization and Immunomodulatory Effects of Polysaccharides from Amomum villosum Lour. on RAW 264.7 Macrophages

Amomum Villosum Lour. (A. villosum) is a folk medicine that has been used for more than 1300 years. However, study of the polysaccharides of A. villosum is seriously neglected. The objectives of this study are to explore the structural characteristics of polysaccharides from A. villosum (AVPs) and their effects on immune cells. In this study, the acidic polysaccharides (AVPG-1 and AVPG-2) were isolated from AVPs and purified via anion exchange and gel filtration chromatography. The structural characteristics of the polysaccharides were characterized by methylation, HPSEC-MALLS-RID, HPLC, FT-IR, SEM, GC-MS and NMR techniques. AVPG-1 with a molecular weight of 514 kDa had the backbone of → 4)-α-d-Glcp-(1 → 3,4)-β-d-Glcp-(1 → 4)-α-d-Glcp-(1 →. AVPG-2 with a higher molecular weight (14800 kDa) comprised a backbone of → 4)-α-d-Glcp-(1 → 3,6)-β-d-Galp-(1 → 4)-α-d-Glcp-(1 →. RAW 264.7 cells were used to investigate the potential effect of AVPG-1 and AVPG-2 on macrophages, and lipopolysaccharide (LPS) was used as a positive control. The results from bioassays showed that AVPG-2 exhibited stronger immunomodulatory activity than AVPG-1. AVPG-2 significantly induced nitric oxide (NO) production as well as the release of interleukin (IL)-6 and tumor necrosis factor alpha (TNF-α), and upregulated phagocytic capacities of RAW 264.7 cells. Real-time PCR analysis revealed that AVPG-2 was able to turn the polarization of macrophages to the M1 direction. These results suggested that AVPs could be explored as potential immunomodulatory agents of the functional foods or complementary medicine.     

Study of the Antioxidant and Anti-Inflammatory Properties of the Biological Extracts of Psophocarpus tetragonolobus Using Two Extraction Methods

Psophocarpus tetragonolobus has long been used in traditional medicine and cuisine. In this study, Psophocarpus tetragonolobus extracts were isolated by maceration and ultrasound-assisted extraction and were evaluated for their antioxidant and anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. The obtained results show that both extracts (maceration and ultrasound) were rich in bioactive molecules and exerted substantial antioxidant and anti-inflammatory effects. The P. tetragonolobus extracts’ treatment in LPS-stimulated RAW264.7 macrophages resulted in a significant downregulation of the expressions of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-1β mRNA. In addition, the P. tetragonolobus extracts’ treatment attenuated inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression. Our observations indicate that there is no significant difference between the two studied extracts of P. tetragonolobus in terms of biological properties (specifically, antioxidant and anti-inflammatory effects. Regardless of the extraction method, P. tetragonolobus could be used for treating diseases related to oxidative stress and inflammatory reactions.     

Nucleophilic substitution reactions of 2,4,6-tris(trinitromethyl)-1,3,5-triazine. 2. interaction of 2,4,6-tris(trinitromethyl)-1,3,5-triazine with primary amines and hexamethyldisilazane

2-R-amino-4,6-bis (trinitromethyl)-1,3,5-triazines have been synthesized, and their structures have been established. Dynamic¹³C NMR spectroscopy has been used to measure the rotational barriers of the tertbutylamino group around the C₍₂₎-NHBu-t bond in 2-(tert-butylamino)-4,6-dichloro-1, 3, 5-triazine and 2-(tertbutylamino)-4,6-dimethoxy-1,3,5-triazine. X-ray diffraction was used to investigate the structure of 2-(tertbutylamino)-4,6-bis (trinitromethyl)-1,3,5-triazine. From the results obtained in this work it has been concluded that the bond between the NHBu-t group and the triazine ring has a partial double-bond character.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, Moscow 117913. Translated from ] Khimiya Geterotsikiicheskikh Soedinenii, No. 5, pp. 679–688 May, 1995. Original article submitted March 7, 1995.