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The strict monitoring and precise measurements of chemical warfare agents (CWAs) in environmental and other complex samples with high accuracy have great practical significance from the forensic an...

Cinnamon (Cinnamomum cassia) is an important spice which is widely consumed in the Indian subcontinent as well as in several other parts of the world. In the present study, NMR spectroscopy showed the presence of cinnamaldehyde to be the major component of the bark. The possible mutagenic effects of cinnamon bark ethanolic extract (CEE, 0.01-1 mg/plate) cinnamon oil (CNO, 0.125-1 mg/plate), and its active component cinnamadehyde (CLD, 0.125-1 mg/plate) were evaluated. Antimutagenic activity of CEE, CNO, and CLD was also tested against various food borne mutagens (heterocyclic amines and aflatoxin B1 (AFB1)) and sodium azide (SA) using Ames assay. Similarly, the antimicrobial activity was studied using agar well diffusion assay against various pathogens. CEE was non-mutagenic in any of the five tester strains of Salmonella typhimurium (TA97a, TA98, TA100, TA102, and TA104) in Ames test. CEE exhibited antimutagenic activity against all the mutagens tested in the higher doses. Additionally, CEE, CNO, and CLD were effective against various pathogens such as Staphylococcus aureus, Proteus vulgaris, S. typhimurium, Klebsiella pneumoniae, and Escherichia coli in the agar well diffusion assay. Promising antimutagenic and antimicrobial properties were shown by the cinnamon bark ethanolic extract and cinnamaldehyde, respectively. Therefore, their role in cancer chemoprevention, as well as a natural antimicrobial agent must be exploited and studied in depth in in vivo conditions.

The performance of MIP is related with the thermodynamic stability of the pre-polymerization complex. The stability of pre-polymerization complex is influenced by functional monomer, cross-linker, and porogen. These factors in conjugation with the microenvironment polarity determine the binding behaviours of MIP. Methylphosphonic acid (MPA), the ultimate degradation product and persistent environmental marker of nerve agents, was selected as target. In present work, 31 P{ 1 H}NMR was employed to optimize imprinting conditions of derivative of MPA. This approach comprised of screening of functional monomer, cross-linker, porogen and stability of pre-polymerization complex before and during polymerization and the MIP was synthesized accordingly. Sorption properties of MIP were elucidated by batch rebinding studies. The selectivity of MIP towards the template was confirmed by comparing its binding with structural analogues of phosphonate esters. These results indicate that 31 P{ 1 H}NMR is a simple and effective method for the rational design of MIP for phosphorus containing environmental contaminants.

The design of experiments has been used for the development of highly efficient and accurate industrial application of quantitative nuclear magnetic resonance (qNMR) spectroscopy. Since these factors are highly dependent on the choice of proper data acquisition and data processing parameters, in this work, seven data acquisition and data processing parameters (excitation pulse width/duration, central frequency, number of scans, sample temperature, acquisition time, line broadening function, and inter scan delay) were investigated and optimized for quantitative proton NMR (qHNMR) experiments to ascertain optimal values. Box Behnken design of experiments was used to arrive at these values by performing minimum number of experiments. To test this methodology, decontamination formulation number two (DS2), a universal field decontaminating reagent of highly toxic chemical warfare agents, was used as a model mixture. Quantification of its components (methyl cellosolve and diethylene triamine) was performed with...

The strict monitoring and precise measurements of chemical warfare agents (CWAs) in environmental and other complex samples with high accuracy have great practical significance from the forensic and Chemical Weapons Convention (CWC) verification point of view. Therefore, this study was aimed to develop an efficient extraction and enrichment method for identification and quantification of toxic agents, especially with high sensitivity and multidetection ability in complex samples. It is the first study on solid-phase extraction (SPE) of CWAs and their related compounds from hydrocarbon backgrounds using covalent triazine-based frameworks (CTFs). This nitrogen-rich CTF sorbent has shown an excellent SPE performance toward sample cleanup by selective elimination of hydrocarbon backgrounds and enrich the CWC related analytes in comparison with the conventional and other reported methods. The best enrichment of the analytes was found with the washing solvent (1 mL of n-hexane) and the extraction solvent (1 mL of dichloromethane). Under the optimized conditions, the SPE method had good linearity in the concentration range of 0.050-10.0 μg mL

The optimized conditions have been reported for efficient, operationally simple and safe oxidative decontamination of chemical warfare agent O-ethyl-S-2-(N,N-diisopropylaminoethyl)methylphosphonothioate (VX) and its non-toxic simulant O,S-diethyl methylphosphonothioate (OSDEMP). A positive chlorine bearing reagent N,N-dichlorovaleramide (NCV) was tested successfully to effect decontamination of these compounds. These compounds were found to undergo instantaneous reaction with NCV in acetonitrile–water medium to form non-toxic products. The reaction was monitored by gas chromatography (GC) and the products were identified by gas chromatography coupled with mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) spectroscopy. The advantages of using this reagent are its low cost of production, ease of synthesis from commercially available raw materials and good shelf life (of more than one year).

Nanotechnology has been a lucrative field of interest for chemists, physicists, biologists, engineers, and even for the scientists working in interdisciplinary sciences. Explicit and novel applications of nanomaterials in nearly all domains make their fabrication inevitable due to their exceptional properties. Nanomaterials find their applications ubiquitously, ranging from conventional antibacterial and antifungal to more advanced fields such as imaging, detoxification, drug delivery, and tissue engineering. However, their amenability in the fields of biomedical and therapeutic sciences is yet to be explored. There is a huge demand to devise characterization strategies for nanomaterials. Several of the biophysical techniques have considerably contributed in solving the problems related to their characterization; albeit, they lack the atomic level resolution. Due to the existence of nanomaterials in various permutations and combinations thereof, comprising different combinations of nanomaterials and ligands for various applications, nuclear magnetic resonance (NMR) spectroscopy can irrevocably analyze diversified range of structural and chemical properties of nanomaterials in both solid and liquid states with a resolution at par to the atomic level, thus justifying the motive of NMR spectroscopy as an unique and prime tool for characterization of nanomaterials. In the current chapter, we aim to bring the contribution of NMR spectroscopy toward nanomaterial characterization by discussing its theoretical aspects, highlighting the practical facet in nanotechnology to colligate these two adorable partners.

We report an efficient procedure for the synthesis of symmetrical disulfanes from organic thiocyanates in the presence of sodium in silica gel at room temperature. By avoiding the use of foul-smelling thiols, the present protocol provides an attractive alternative to existing methods for the preparation of symmetrical disulfanes.

We report herein a new, sensitive and efficient method for detection, identification and quantification of cyanide in water samples. Cyanide was converted (>95% yield) to its versatile and stable derivative, 1-cyano-2,2,2-trifluoro-1-phenylethyl acetate (CTPA).The crude reaction mixture was directly subjected to high resolution fluorine-19 nuclear magnetic resonance (19F{1H} NMR) spectroscopy. In order to do away with signal overlap and dynamic range problems associated with 1H NMR spectroscopy, liquid chromatography with UV detection hyphenated to online solid phase extraction (LC–UV–SPE) was performed. The trapped and enriched CTPA was thereafter subjected to offline 1H NMR spectroscopy. In this way the δ1H, δ19F spectral signatures and LC–UV retention time were used for specific detection and identification and quantification of cyanide. The three techniques (viz. LC–UV and LC–UV–SPE followed by offline 1H NMR and 19F{1H} NMR spectroscopy) demonstrated good linearity (r2 > 0.99), reproducibility (inter-day RSD: 1.43–1.89%, 2.60–2.80%, 1.42–1.60; intra-day: RSD 1.20–1.38%, 3.21–3.25%, 1.00–1.19%), accuracy (recoveries: 95.1–97.2%, 77.5–82.8%, 96.8–98.9%) and LODs (1.31 μg/mL, 4.24 μg/mL, and 2.14 μg/mL) respectively. Total time required for the analysis was ∼3 h. Utility of the method was demonstrated by the detection and identification of spiked water samples. Since the derivative CTPA was volatile, could also be analyzed by GC–MS and GC–FTIR instruments.

An efficient and operationally simple method for chemical decontamination of sulfur mustard (HD) has been reported herein. A chlorine-bearing reagent N,N-dichlorourethane was developed to deactivate HD in aqueous (acetonitrile/water, 80/20) medium. This decontamination reaction was monitored by gas chromatography–mass spectrometry and NMR spectroscopy. This reagent is highly efficient, stable, economical, and easy to synthesize and leads to instant decontamination of HD. The reaction was found to instantaneously and completely convert HD to innocent products at different temperatures (−20 to 40 °C).

We report an efficient procedure for the synthesis of symmetrical disulfanes from organic thiocyanates in the presence of sodium in silica gel at room temperature. By avoiding the use of foul-smelling thiols, the present protocol provides an attractive alternative to existing methods for the preparation of symmetrical disulfanes.

An efficient and operationally simple method for the chemical decontamination of sulfur mustard (HD) has been reported herein. A newly synthesized (positive chlorine bearing) reagent N,N-dichlorovaleramide has been utilized for this purpose. Decontamination has been achieved in aqueous and aprotic media. The reaction was monitored by gas chromatography–mass spectrometry and NMR spectroscopy. This reagent is more effective, stable, economical, and easy to synthesize and leads to instant decontamination of HD. The reaction was found to instantaneously and completely convert HD to innocuous products at different temperatures (−10 to 25 °C).

A high-resolution phosphorus-31 nuclear magnetic resonance (NMR) spectroscopic method has been developed for detection, identification and quantification of non-phosphorus markers of toxic nerve agents (soman and V-class), vesicants (HD, HN-2, HN-3), and incapacitating agent (Bz). These analytes were converted to phosphorus-containing derivatives via phosphitylation reaction of their hydroxyl and sulfhydryl functions (using 2-chloro-4,4,5,5-tetramethyl-1,3,2-dioxaphospholane). This was followed by 31P{1H} and 31P NMR analysis of these derivatives. The chemical shifts (δ) and coupling constants (3 J P–H) of derivatives were used for their specific detection and identification. The method allowed clear distinction between the alcohols and thiols. The lower limits of detection of these analytes were found to be between 12 and 28 μg obtained from 128 transients of 31P{1H} quantitative NMR experiments. Utility of the method was ensured by the detection and identification of triethanolamine present (at an original concentration of 5 μg/mL) in an aqueous sample from 28th OPCW Official Proficiency Tests.

A rapid selective and accurate quantitative (1)H NMR method was developed for the simultaneous analysis of obidoxime chloride and atropine sulfate, the active components in parenteral injection devices (PID) used for the emergency treatment of poisoning by toxic organophosphates. The spectra were acquired in 90% H(2)O-10% D(2)O using sodium 3-(trimethylsilyl)-1-propane sulfonate hydrate as the internal standard. Both synthetic mixtures and dosage forms were assayed. The results were compared with those obtained from a reported HPLC method.

A series of bis-pyridinium oximes connected by xylene linker were synthesized and their in-vitro reactivation potential was evaluated against acetylcholinesterase (AChE) inhibited by nerve agent, sarin. Among the synthesized compounds, α,α′xylene-bis-[3,3′-(hydroxyiminomethyl) pyridinium] dibromide (3b) was found to be most potent reactivator for AChE inhibited by sarin. The oxime 3b exhibits 34% regeneration of inhibited AChE, in comparison to 20 and 15% regeneration by 2-PAM and obidoxime, respectively, at a concentration of 10−4 M within 10 min.

As received cenospheres obtained from Rihand Super Thermal Power Plant, Uttar Pradesh,India, were processed using sink float method. The solvent system consisted of 1% TEALS (Triethanolamine lauryl sulphate) in acetone. Further flotation of the float with the same solvent system led to another float. Various fractions thus obtained were characterized in respect of their chemical, mineralogical, and morphological properties. The float obtained from second flotation was richer in cenospheres, which are round and within a small size range. The residues obtained were broken spheres. Phase-mineralogical analysis has revealed mullite enrichment in the floats. Chemical composition of the various fractions does not indicate high concentration of harmful elements. SEM analysis leads to the conclusion that the cenospheres are essentially open-pore type. Based on such experimental observations, various potential uses have been suggested.

Retrospective detection and identification of markers of chemical warfare agents are important aspects of verification of the Chemical Weapons Convention. Alkyl alkylphosphonic acids (AAPAs) and alkylphosphonic acids (APAs) are important markers of nerve agents. We describe the development and optimization of a new gas chromatography/mass spectrometry (GC/MS) injection port fluorination method for the derivatization of AAPAs and APAs. The process involved the injection of acids with trifluoroacetic anhydride in GC/MS, where acids are converted into their corresponding volatile fluorides. Various reaction conditions such as fluorinating agent, injection port temperature and splitless time were optimized. The maximum reaction efficiency of the acids with trifluoroacetic anhydride was observed at 230°C injection port temperature with a splitless time of 2 min. APAs showed best analytical efficiencies at 400°C injection port temperature, while the other conditions were similar to those of AAPAs. The linearities of response for APAs and AAPAs were in the range of 1–25 and 5–100 µg mL−1, respectively, with limits of detection ranging from 500 pg to 800 ng mL−1. Copyright © 2007 John Wiley & Sons, Ltd.

High altitude medicine is an emerging subspecialty that has crosscutting relevance for 21(st) century science and society: from sports medicine and aerospace industry to urban and rural communities living in high altitude. Recreational travel to high altitude has also become increasingly popular. Rarely has the biology of high altitude biology been studied using systems sciences and omics high-throughput technologies. In the present study, 1H-NMR-based metabolomics, along with multivariate analyses, were employed in a preclinical rat model to characterize the urinary metabolome under hypobaric hypoxia stress. Rats were exposed to simulated altitude of 6700 m above the sea level. The urine samples were collected from pre- and post-exposure (1, 3, 7, and 14 days) of hypobaric hypoxia. Metabolomics urinalysis showed alterations in TCA cycle metabolites (citrate, α-ketoglutarate), cell membrane metabolism (choline), gut micro-flora metabolism (hippurate, phenylacetylglycine), and others (N-acetyl glutamate, creatine, taurine) in response to hypobaric hypoxia. Taurine, a potential biomarker of hepatic function, was elevated after 3 days of hypobaric hypoxia, which indicates altered liver functioning. Liver histopathology confirmed the damage to tissue architecture due to hypobaric hypoxia. The metabolic pathway analysis identified taurine metabolism and TCA as important pathways that might have contributed to hypobaric hypoxia-induced pathophysiology. This study demonstrates the use of metabolomics as a promising tool for discovery and understanding of novel biochemical responses to hypobaric hypoxia exposure, providing new insight in the field of high altitude medicine and the attendant health problems that occur in response to high altitude. The findings reported here also have potential relevance for sports medicine and aviation sciences.

We demonstrate herein the application of selective derivatization method that converts volatile and labile trialkylphosphites (TAPs) into virtually non-volatile, thermally stable, and UV absorbing derivatives. After simple sample preparation, purification/enrichment of the derivatives was achieved by using high performance liquid chromatography (HPLC) coupled to on-line post column solid phase extraction (SPE) system. These derivatives were subjected to (31)P{(1)H} NMR and 1D-selTOCSY experiments. Conclusive identification was achieved on the basis of their HPLC retention time and NMR spectral signatures ( [Formula: see text] , (n)JH-H, and (3)JP-H). This method was tested for the unambiguous identification of a mixture containing low concentrations (∼10μgmL(-1)) of trimethylphosphite (TMP), triethylphosphite (TEP), triisopropylphosphite (TIP), and tributylphosphite (TBP) along with a high concentration of irrelevant background chemicals. It offered a high dynamic range and good detection limit and recovery (>75%) without the need for special NMR probe heads or exotic NMR experiments.

Direct conversion of phosphorus(V) chlorides to the corresponding phosphorus(V) fluorides was achieved using a solid reagent, tetrabutylammonium tetra (tert-butyl alcohol) coordinated fluoride. The phosphorus(V) fluorides were directly synthesized and efficiently isolated in very good yields.

An efficient and operationally simple method is developed for the synthesis of dialkyl chlorophosphates from dialkylphosphites using a new chlorine bearing reagent, N,N-dichloro poly(styrene-co-divinyl benzene) sulfonamide in the form of polymeric beads. The reagent afforded dialkyl chlorophosphates at room temperature, and is recyclable.

We report herein a new, sensitive and efficient method for detection, identification and quantification of cyanide in water samples. Cyanide was converted (95% yield) to its versatile and stable derivative, 1-cyano-2,2,2-trifluoro-1-phenylethyl acetate (CTPA).The crude reaction mixture was directly subjected to high resolution fluorine-19 nuclear magnetic resonance ((19)F{(1)H} NMR) spectroscopy. In order to do away with signal overlap and dynamic range problems associated with (1)H NMR spectroscopy, liquid chromatography with UV detection hyphenated to online solid phase extraction (LC-UV-SPE) was performed. The trapped and enriched CTPA was thereafter subjected to offline (1)H NMR spectroscopy. In this way the δ(1)H, δ(19)F spectral signatures and LC-UV retention time were used for specific detection and identification and quantification of cyanide. The three techniques (viz. LC-UV and LC-UV-SPE followed by offline (1)H NMR and (19)F{(1)H} NMR spectroscopy) demonstrated good linearity (r(2)0.99), reproducibility (inter-day RSD: 1.43-1.89%, 2.60-2.80%, 1.42-1.60; intra-day: RSD 1.20-1.38%, 3.21-3.25%, 1.00-1.19%), accuracy (recoveries: 95.1-97.2%, 77.5-82.8%, 96.8-98.9%) and LODs (1.31 μg/mL, 4.24 μg/mL, and 2.14 μg/mL) respectively. Total time required for the analysis was ∼3 h. Utility of the method was demonstrated by the detection and identification of spiked water samples. Since the derivative CTPA was volatile, could also be analyzed by GC-MS and GC-FTIR instruments.

substituted thioamides starting from acyl halides and amines is an attractive method as it allows an easy introduction of diverse building blocks for constructing desired thioamides. This is a two step procedure. For avoiding a lengthy separation process and purification of intermediate, one-pot preparation techniques are highly preferred. The potential of one-pot procedure is enhanced if applied with microwave heating under solvent-free condition

The combination of dispersive solid-phase extraction (DSPE) and Fourier-transform infrared (FTIR) spectroscopy is presented for detection and quantification of markers and simulants of nerve agents. Hydrophilic–lipophilic balance (HLB) sorbent was used for extraction and enrichment of organophosphonates from water. When the extraction efficiency of DSPE was compared with that of conventional solid-phase extraction (SPE), DSPE was more efficient. Extraction conditions such as extraction time, and type and quantity of sorbent material were optimized. In DSPE, extracted analytes are detected and quantified on the sorbent using FTIR as analytical technique. Absorbance in FTIR due to P–O–C stretching was used for detection and quantification. Infrared absorbance of different analytes were compared by determining their molar absorptivities (e max). Quantitative analyses were performed employing modified Beer’s law, and relative standard deviations (RSDs) for intraday repeatability and interday reproducibility were found to be in the range 0.30–0.90% and 0.10–0.80% respectively. The limit of detection (LOD) was 5–10 μg mL−1. The applicability of the method was tested with an unknown sample prepared by mimicking the sample obtained in an international official proficiency test.

The detection and identification of the degradation products of nitrogen mustard and nerve agent VX by high performance liquid chromatography coupled to on-line solid-phase extraction-nuclear magnetic resonance spectroscopy (HPLC-UV-SPE-NMR) were demonstrated. The analytes selected for the study were N , N -dimethylaminoethanol (DMAE), N , N -diethylaminoethanol (DEAE), N , N -diisopropylaminoethanol (DIAE) and triethanolamine (TEA). Offline solid-phase extraction (SPE) followed by derivatization was applied to eliminate the interferents and make the analytes amenable for UV detection. Thereafter, chromatographically separated derivatives were trapped on on-line SPE cartridges. They were subsequently eluted and 1 H NMR and COSY spectra were obtained. The overall detection limits of the LC-UV-SPE-NMR method for the mentioned analytes were found to be 18, 23, 25, and 32 mg/L respectively. Applicability of the method to real samples was demonstrated by the analysis of samples provided during the 22nd OPCW official proficiency test. The method gave reproducible NMR spectra devoid of intense background signals.

Direct conversion of phosphorus(V) chlorides to the corresponding phosphorus(V) fluorides was achieved using a solid reagent, tetrabutylammonium tetra (tert-butyl alcohol) coordinated fluoride. The phosphorus(V) fluorides were directly synthesized and efficiently isolated in very good yields.

A convenient, highly efficient, safe microwave-mediated Salkylation of O,O’-dialkyl thiophosphate has been reported. Clean and rapid S-alkylation of thiophosphates can be achieved by irradiating a mixture of dialkylthiophosphate salt and alkyl halide under microwave for a brief period. Alkylation occurs exclusively at sulfur to provide S-alkylated products. Through a simple workup, pure compounds have been obtained easily in good yields.

We describe the gas chromatography/mass spectrometric (GC/MS) analysis of O-alkyl methylphosphinates (AMPs), which are included in Schedule 2B4 chemicals in the Chemical Weapons Convention (CWC). GC/MS analysis of a variety of AMPs and their deuterated analogs revealed that their fragmentations were determined by α-cleavages, McLafferty +1 and hydrogen rearrangement. Based on the obtained electron ionization mass spectra of AMPs, the fragmentation routes were rationalized, which were substantiated by the GC/MS analysis of deuterated analogs.

An efficient and operationally simple method is developed for the synthesis of dialkyl chlorophosphates from dialkylphosphites using a new chlorine bearing reagent, N,N-dichloro poly(styrene-co-divinyl benzene) sulfonamide in the form of polymeric beads. The reagent afforded dialkyl chlorophosphates at room temperature, and is recyclable.

This paper details an on-flow liquid chromatography-ultraviolet-nuclear magnetic resonance (LC-UV-NMR) method for the retrospective detection and identification of alkyl alkylphosphonic acids (AAPAs) and alkylphosphonic acids (APAs), the markers of the toxic nerve agents for verification of the Chemical Weapons Convention (CWC). Initially, the LC-UV-NMR parameters were optimized for benzyl derivatives of the APAs and AAPAs. The optimized parameters include stationary phase C(18), mobile phase methanol:water 78:22 (v/v), UV detection at 268nm and (1)H NMR acquisition conditions. The protocol described herein allowed the detection of analytes through acquisition of high quality NMR spectra from the aqueous solution of the APAs and AAPAs with high concentrations of interfering background chemicals which have been removed by preceding sample preparation. The reported standard deviation for the quantification is related to the UV detector which showed relative standard deviations (RSDs) for quantification within +/-1.1%, while lower limit of detection upto 16mug (in mug absolute) for the NMR detector. Finally the developed LC-UV-NMR method was applied to identify the APAs and AAPAs in real water samples, consequent to solid phase extraction and derivatization. The method is fast (total experiment time approximately 2h), sensitive, rugged and efficient.

This article describes a one pot, solvent free, microwave assisted synthesis of O,O-dialkyl dialkylpyrophosphonates (DADAPP) from O-alkyl alkylphosphonic chlorides 2a–j with 4-dimethylaminopyridine (DMAP) in the presence of water under microwave irradiation. The reaction takes place by the phosphonium salts, which are converted into the DADAPPs 4a–j. These DADAPPs are important markers of chemical warfare agents sarin, soman, and VX and their analogues. The method has several advantages over the conventional methods such as operational simplicity, high yield, and reduced reaction time.

Bis-pyridinium oximes connected by methoxy alkane ether linker were synthesized and their in vitro reactivation efficacy was evaluated for sarin inhibited AChE. Reactivation efficacy of synthesized compounds was compared with 2-PAM and obidoxime. Among the synthesized compounds, 1,2-dimethoxy ethylene bis-[3,3'-(hydroxyiminomethyl) pyridinium] dichloride (3P-2) and 1,3-dimethoxy propylene bis-[3,3'-(hydroxyiminomethyl) pyridinium] dichloride (3P-3) were found to be most potent reactivators for AChE inhibited by nerve agent sarin. 3P-2 and 3P-3, respectively exhibited 80% and 69% regeneration of inhibited AChE, whereas 2-PAM (well known antidote for nerve agent poisoning) showed 42% regeneration.

We report herein the synthesis, characterization, stability study of a new solid supported derivatizing agent, N-benzyl-N-nitroso-4-poly(styrene-co-divinylbenzene)sulfonamide beads, for the preparation of phenyldiazomethane (PDM). The active component loading was found to be 2.0 ± 0.1 mmol g−1. This derivatizing agent is easy to synthesize and purify. The impurities and byproducts generated during the formation of PDM remain bound to the polymer backbone. These byproducts can be easily removed by filtration. Thus, pure PDM is obtained without the need for further purification. Due to the formation of a dilute solution of PDM, the chances of explosion and intoxication are minimized. The PDM from this derivatizing agent was used for the benzylation of a variety of acids. We have evaluated this derivatizing agent for the benzylation of alkylphosphonic acids (APAs) and alkyl alkylphosphonic acids (AAPAs). Subsequently, this reagent was applied for analysis of a real sample containing pinacolyl methylphosphonic acid by onflow LC-UV-1H NMR analysis.

The formation of trimethylsilyl (TMS) derivative of hydrolyzed product of nerve agent VX, namely S-2-(N,N-diisopropylaminoethyl) methylphosphonothiolate (EA-2192), was reported to be hampered due to its zwiterionic character. Contrary to this assumption, we have synthesized and analyzed the TMS derivative of EA-2192 and its analogues. Initially, the problem of non-detectability in GC-MS analysis was found to be due to their condensation followed by decomposition on GC column. An optimized temperature program, starting from 175 °C column temperature, favours partitioning of TMS derivatives of EA-2192 and its analogues into mobile phase, which facilitates their detection. It reduces their on-column condensation and decomposition. Excellent reproducibility (

This article describes a one pot, solvent free, microwave assisted synthesis of O,O-dialkyl dialkylpyrophosphonates (DADAPP) from O-alkyl alkylphosphonic chlorides 2a–j with 4-dimethylaminopyridine (DMAP) in the presence of water under microwave irradiation. The reaction takes place by the phosphonium salts, which are converted into the DADAPPs 4a–j. These DADAPPs are important markers of chemical warfare agents sarin, soman, and VX and their analogues. The method has several advantages over the conventional methods such as operational simplicity, high yield, and reduced reaction time.

The extractability of the O,O'-dialkyl methylphosphonates, (the important markers of nerve agents) included in the schedule 2B4 of the Chemical Weapons Convention (CWC) has been studied by NMR, the aim being the optimisation of extraction protocols routinely used for the identification of Convention-related Chemicals (CRCs) during Official Proficiency Tests (OPTs) conducted by the Organization for Prohibition of Chemical Weapons (OPCW) and for the off-site analysis of real field samples. The technique is easy to optimise, fast, nondestructive, and shows excellent reproducibility. Defence Science Journal, 2010, 60(5), pp.502-506 , DOI:http://dx.doi.org/10.14429/dsj.60.573