Synthesis of 2,4,6-Trinitrotoluene (TNT) Using Flow Chemistry.

This paper describes the nitration of 2,4-dinitrotoluene (DNT) and its conversion to 2,4,6-trinitrotoluene (TNT) at a gram scale with the use of a fully automated flow chemistry system. The conversion of DNT to TNT traditionally requires the use of highly hazardous reagents like fuming sulfuric acid (oleum), fuming nitric acid (90-100%), and elevated temperatures. Flow chemistry offers advantages compared to conventional syntheses including a high degree of safety and simpler multistep automation.

In vitro and in vivo antiplasmodial activity of extracts and isolated constituents of Alstonia congensis root bark.

Ethnopharmacological Relevance: An aqueous decoction of root bark of Alstonia congensis Engl. (Apocynaceae) is used in several African countries to treat various ailments including malaria.

Materials And Methods: Extracts of different polarity and isolated constituents were tested in vitro for their antiplasmodial activity against the chloroquine-resistant strain Plasmodium falciparum K1 and the chloroquine-sensitive strain P.

and Antidiabetic and Antimicrobial Evaluation of Constituents from ().

(Wall.) Janch (or (Wall.) Betsche is a well-known medicinal plant in Pakistan that is traditionally used in diabetic and inflammatory conditions.

Isolation and Structure Elucidation by LC-DAD-MS and LC-DAD-SPE-NMR of Cyclopeptide Alkaloids from the Roots of Ziziphus oxyphylla and Evaluation of Their Antiplasmodial Activity.

Nine cyclopeptide alkaloids (1-9), of which five (compounds 2, 3, 5, 8, and 9) are described herein for the first time, were isolated from roots of Ziziphus oxyphylla by means of conventional separation methods as well as semipreparative HPLC with DAD and ESIMS detection and LC-DAD-SPE-NMR. Structure elucidation was done by spectroscopic means. Nummularine-R (1), a previously known constituent from this species, was isolated along with its new derivatives O-desmethylnummularine-R (2) and O-desmethylnummularine-R N-oxide (3).

Saponins and Flavonoids from an Infusion of Herniaria hirsuta.

Stone diseases present a major health problem in the Western society, since both urinary and biliary stones occur with a relatively high prevalence of 10-12 % and 10-20 %, respectively, and demonstrate a high recurrence rate. At the moment treatment is mainly based on interventional procedures, or prophylactic and dissolution therapy. However, many of the current drugs cause severe side effects, and therefore, there is an increasing interest in natural medicines.

Antiprotozoal and Antiglycation Activities of Sesquiterpene Coumarins from Ferula narthex Exudate.

The exudate of Boiss. (Apiaceae) is widely used in the Indian subcontinent as a spice and because of its health effects. Six sesquiterpene coumarins have been isolated from this exudate: feselol, ligupersin A, asacoumarin A, 8'--acetyl-asacoumarin A, 10'-karatavacinol and 10'-acetyl-karatavacinol.

Treatment with Rhus tripartita extract curtails isoproterenol-elicited cardiotoxicity and oxidative stress in rats.

Background: Consumption of plant-derived nutraceuticals and crude drugs in traditional medicine is widely believed to confer beneficial effects in thwarting the progression of cardiovascular diseases. Rhus tripartita (family Anacardiaceae) has been traditionally used to treat a wide range of ailments.

Methods: In the present study we investigated the protective effects of an alcoholic extract of the stem part of Rhus tripartita male genotype (RTSM) on experimentally induced myocardial injury in rats.

In Vitro Neuroprotective and Anti-Inflammatory Activities of Natural and Semi-Synthetic Spirosteroid Analogues.

Two spirosteroid analogues were synthesized and evaluated for their in vitro neuroprotective activities in PC12 cells, against glutamate-induced excitotoxicity and mitochondrial damage in glucose deprivation conditions, as well as their anti-inflammatory potential in LPS/IFNγ-stimulated microglia primary cultures. We also evaluated the in vitro anti-excitotoxic and anti-inflammatory activities of natural and endogenous steroids. Our results show that the plant-derived steroid solasodine decreased PC12 glutamate-induced excitotoxicity, but not the cell death induced by mitochondrial damage and glucose deprivation.

Phytochemical and Pharmacological Investigations on Nymphoides indica Leaf Extracts.

Nymphoides indica (L.) Kuntze (Menyanthaceae) is traditionally used in the Indian subcontinent. However, scientific data reporting its constituents are poor.

Edible coating composed of chitosan and Salvia fruticosa Mill. extract for the control of grey mould of table grapes.

Background: Consumer concerns regarding high-quality produce, free of pesticide residues, direct research towards disease management strategies that minimise or even exclude the use of synthetic chemistries in crop production. The efficacy of a chitosan-based edible coating combined with the acetonic extract of Salvia fruticosa Mill. (ASF) was assessed against the grey mould of table grapes.

Antioxidant and Antiglycating Constituents from Leaves of Ziziphus oxyphylla and Cedrela serrata.

Ziziphus oxyphylla and Cedrela Serrata plants have a folkloric use in Pakistan for treatments of different ailments, i.e., Jaundice, Hepatitis, Diabetes, and antimicrobial.

In vitro biotransformation of tris(2-butoxyethyl) phosphate (TBOEP) in human liver and serum.

Tris(2-butoxyethyl) phosphate (TBOEP) is a plasticizer present in indoor dust, reaching levels of several micrograms per gram. Such levels could lead to significant daily exposure of adults and children. Currently, no toxicokinetic data are available to estimate TBOEP clearance in humans after uptake and therefore, one objective of this study was to investigate intrinsic clearance of TBOEP by human liver microsome (HLM) and serum enzymes.

HPLC-SPE-NMR characterization of major metabolites in Salvia fruticosa Mill. extract with antifungal potential: relevance of carnosic acid, carnosol, and hispidulin.

Plant pathogenic fungi are considered of significant economic importance for adversely affecting both quantitatively and qualitatively fresh and processed produce. Extracts of Salvia fruticosa were initially screened for their antifungal activity, and the ethyl acetate fraction, being the most active, was further analyzed using HPLC-SPE-NMR hyphenation. The methoxylated flavones hispidulin, salvigenin, and cirsimaritin and the diterpenes carnosic acid, carnosol, and 12-methoxycarnosic acid were identified as the major components of the extract.

Automated analytical standard production with supercritical fluid chromatography for the quantification of bioactive C17-polyacetylenes: a case study on food processing waste.

Food processing enterprises produce enormous amounts of organic waste that contains valuable phytochemicals (e.g. C17-polyacetylenes).

Hydrogen bonding probes of phenol -OH groups.

Correlations between hydrogen bonds and solvent effects on phenol -OH proton shieldings, temperature coefficients (Δδ/ΔT) and effects on OH diffusion coefficients for numerous phenolic acids, flavonols, flavones, and oleuropein derivatives of biological interest were investigated in several organic solvents and were shown to serve as reliable indicators of hydrogen bonding and solvation state of -OH groups. The temperature coefficients span a range of -0.5 to -12.

Rapid and direct low micromolar NMR method for the simultaneous detection of hydrogen peroxide and phenolics in plant extracts.

A rapid and direct low micromolar ¹H NMR method for the simultaneous identification and quantification of hydrogen peroxide and phenolic compounds in plant extracts was developed. The method is based on the highly deshielded ¹H NMR signal of H₂O₂ at ∼10.30 ppm in DMSO-d₆ and the combined use of picric acid and low temperature, near the freezing point of the solution, in order to achieve the minimum proton exchange rate.

Unprecedented ultra-high-resolution hydroxy group (1)H NMR spectroscopic analysis of plant extracts.

A general method is demonstrated for obtaining ultra-high resolution in the phenolic hydroxy group 1H NMR spectroscopic region, in DMSO-d6 solution, with the addition of picric acid. Line-width reduction by a factor of over 100 was observed, which resulted in line-widths ranging from 1.6 to 0.

Antimicrobial and efflux pump inhibitory activity of caffeoylquinic acids from Artemisia absinthium against gram-positive pathogenic bacteria.

Background: Traditional antibiotics are increasingly suffering from the emergence of multidrug resistance amongst pathogenic bacteria leading to a range of novel approaches to control microbial infections being investigated as potential alternative treatments. One plausible antimicrobial alternative could be the combination of conventional antimicrobial agents/antibiotics with small molecules which block multidrug efflux systems known as efflux pump inhibitors. Bioassay-driven purification and structural determination of compounds from plant sources have yielded a number of pump inhibitors which acted against gram positive bacteria.

A new method for the determination of free L-carnitine in serum samples based on high field single quantum coherence filtering 1H-NMR spectroscopy.

The rapid and accurate determination of specific metabolites present in biofluids is a very demanding task which is essential in both medicine and chemistry. L-carnitine (3-hydroxy-4-N-trimethylammonium butyrate) is an important metabolite which participates in a series of biological paths and therefore its determination is of diagnostic importance. A single quantum coherence filtering (1)H NMR methodology was used for the accurate and rapid determination of L-carnitine in human serum samples.

Tris-(hydroxyamino)triazines: high-affinity chelating tridentate O,N,O-hydroxylamine ligand for the cis-V(V)O2(+) cation.

The treatment of the trichloro-1,3,5-triazine with N-methylhydroxylamine hydrochloride results in the replacement of the three chlorine atoms of the triazine ring with the function -N(OH)CH(3) yielding the symmetrical tris-(hydroxyamino)triazine ligand H(3)trihyat. Reaction of the ligand H(3)trihyat with NaV(V)O(3) in aqueous solution followed by addition of Ph(4)PCl gave the mononuclear vanadium(V) compound Ph(4)P[V(V)O(2)(Htrihyat)] (1). The structure of compound 1 was determined by X-ray crystallography and indicates that this compound has a distorted square-pyramidal arrangement around vanadium.

Contribution of flavonoids to the overall radical scavenging activity of olive (Olea europaea L.) leaf polar extracts.

The contribution of flavonoids to the overall radical scavenging activity of olive leaf polar extracts, known to be good sources of oleuropein related compounds, was examined. Off line and on line HPLC-DPPH(*) assays were employed, whereas flavonoid content was estimated colorimetrically. Individual flavonoid composition was first assessed by RP-HPLC coupled with diode array and fluorescence detectors and verified by LC-MS detection system.

Unexpected synthesis of an unsymmetrical mu-oxido divanadium(V) compound through a reductive cleavage of a N-O bond and cleavage-hydrolysis of a C-N bond of an N,N-disubstituted bis-(hydroxylamino) ligand.

Reaction of the N,N-disubstituted bis-(hydroxylamino) ligand 2,6-bis[hydroxy(methyl)amino]-4-morpholino-1,3,5-triazine, H(2)bihyat, with V(IV)OSO(4).5H(2)O in water for 6 h followed by the addition of methyl alcohol resulted in the isolation of the unsymmetrical mu-oxido divanadium(V) compound [V(V)(2)O(2)(mu(2)-O)(bihyat)(hyta)(hyto)].3H(2)O (1.

Rapid and novel discrimination and quantification of oleanolic and ursolic acids in complex plant extracts using two-dimensional nuclear magnetic resonance spectroscopy-Comparison with HPLC methods.

A novel strategy for NMR analysis of mixtures of oleanolic and ursolic acids that occur in natural products is described. These important phytochemicals have similar structure and their discrimination and quantification is rather difficult. We report herein the combined use of proton-carbon heteronuclear single-quantum coherence ((1)H-(13)C HSQC) and proton-carbon heteronuclear multiple-bond correlation ((1)H-(13)C HMBC) NMR spectroscopy, in the identification and quantitation of oleanolic acid (OA) and ursolic acid (UA)in plant extracts of the Lamiaceae and Oleaceae family.

Phytochemicals in olive-leaf extracts and their antiproliferative activity against cancer and endothelial cells.

Olive oil compounds is a dynamic research area because Mediterranean diet has been shown to protect against cardiovascular disease and cancer. Olive leaves, an easily available natural material of low cost, share possibly a similar wealth of health benefiting bioactive phytochemicals. In this work, we investigated the antioxidant potency and antiproliferative activity against cancer and endothelial cells of water and methanol olive leaves extracts and analyzed their content in phytochemicals using LC-MS and LC-UV-SPE-NMR hyphenated techniques.