Immobilized Horseradish Peroxidase on Enriched Diazo-Activated Silica Gel Harnessed High Biocatalytic Performance at a Steady State in Organic Solvent.

Dimethyldichlorosilane (DMDCS), an efficient silane coupling reagent appearing between the -OH groups of silica gel (SG) and picric acid, instantaneously produces a derivative enriched with nitro groups. The nitro group acting as an end-cap terminates the reaction and subsequently was converted into diazo to couple tyrosine's phenol ring via its -carbon, the inert center to immobilize horseradish peroxidase (HRP) in a multipoint mode. It maintains the status quo of the native enzyme's protein folding and the entire protein groups' chemistry.

Reductions of Arenes using a Magnesium-Dinitrogen Complex.

In this contribution, we present "Birch-type", and other reductions of simple arenes by the potassium salt of an anionic magnesium dinitrogen complex, [{K(NON)Mg}(μ-N)] (NON=4,5-bis(2,4,6-tricyclohexylanilido)-2,7-diethyl-9,9-dimethyl-xanthene), which acts as a masked dimagnesium(I) diradical in these reactions. This reagent is non-hazardous, easy-to-handle, and in some cases provides access to 1,4-cyclohexadiene reduction products under relatively mild reaction conditions. This system works effectively to reduce benzene, naphthalene and anthracene through magnesium-bound "Birch-type" reduction intermediates.

Steric control of Mg-Mg bond formation N activation in the reduction of bulky magnesium diamide complexes.

Reduction of the magnesium(II) diamide [Mg(NON)] (NON = 4,5-bis(2,4,6-triisopropylanilido)-2,7-diethyl-9,9-dimethyl-xanthene) with 5% w/w K/KI leads to a good yield of a dianionic dimagnesium(I) species, as its potassium salt, [{K(NON)Mg}]. An X-ray crystallographic analysis shows the molecule to contain a very long Mg-Mg bond (3.137(2) Å).

Synthesis of α-Seleno Boronates via Diboration of Carbonyl Compounds.

A method has been described for accessing α-seleno alkyl boronates. The selenoboration was achieved via the diboration of carbonyl compounds to give α-oxyl boronates, which then undergo 1,2-metalate rearrangement in the presence of lithium selenolates and trifluoroacetic anhydride (TFAA). A variety of structurally diverse substrates were compatible with this protocol and efficiently provides difunctionalized products from simple starting materials.

Coordination and Activation of N at Low-Valent Magnesium using a Heterobimetallic Approach: Synthesis and Reactivity of a Masked Dimagnesium Diradical.

The activation of dinitrogen (N ) by transition metals is central to the highly energy intensive, heterogeneous Haber-Bosch process. Considerable progress has been made towards more sustainable homogeneous activations of N with d- and f-block metals, though little success has been had with main group metals. Here we report that the reduction of a bulky magnesium(II) amide [( NON)Mg] ( NON=4,5-bis(2,4,6-tricyclohexylanilido)-2,7-diethyl-9,9-dimethyl-xanthene) with 5 % w/w K/KI yields the magnesium-N complex [{K( NON)Mg} (μ-N )].

Approach to the Synthesis of -Thiolated Alkylboronates via Cobalt-Catalyzed Diboration of Aldehydes.

A new method has been developed for the sequential -thioborylation of readily available aldehydes via the cobalt-catalyzed diboration reaction. The -heterocyclic carbene (NHC)-cobalt complex has been used as a catalyst for the diboration of aldehydes to generate α-oxyl boronic esters, which react with lithium thiolates to form a tetracoordinate boronate species, which undergoes 1,2-metalate rearrangement in the presence of trifluoroacetic anhydride. The stepwise functionalization of the boryl and thiol moiety of the products enriches the chemical toolbox of diverse organic synthesis.

Decision tree learning in Neo4j on homogeneous and unconnected graph nodes from biological and clinical datasets.

Background: Graph databases enable efficient storage of heterogeneous, highly-interlinked data, such as clinical data. Subsequently, researchers can extract relevant features from these datasets and apply machine learning for diagnosis, biomarker discovery, or understanding pathogenesis.

Methods: To facilitate machine learning and save time for extracting data from the graph database, we developed and optimized Decision Tree Plug-in (DTP) containing 24 procedures to generate and evaluate decision trees directly in the graph database Neo4j on homogeneous and unconnected nodes.

Reductive activation of N using a calcium/potassium bimetallic system supported by an extremely bulky diamide ligand.

An extremely bulky xanthene bridged diamide ligand (NON = 4,5-bis(2,4,6-tricyclohexylanilido)-2,7-diethyl-9,9-dimethyl-xanthene) has been developed and used to prepare two monomeric diamido-calcium complexes [(NON)Ca(D)] (D = THF, = 2, 3; D = toluene, = 1, 4). Reduction of 4 with 5% w/w K/KI under an N atmosphere gave the first well-defined, hetero-bimetallic s-block complex of activated dinitrogen, [{K(NON)Ca}(μ-η:η-N)] 5, presumably a transient calcium(I) intermediate.

Dissipation behaviour and risk assessment of fipronil and its metabolites in paddy ecosystem using GC-ECD and confirmation by GC-MS/MS.

Fipronil -a broad spectrum phenylpyrazole insecticide has high level of toxicity towards environment. Therefore, an easy and reliable analytical method was developed for residue estimation of fipronil to ensure food and environmental safety. A modified QuEChERS technique was followed for estimation of fipronil (5% SC) in paddy ecosystem using GC-ECD and confirmation by GC-MS/MS.

Evaluation of Functional Outcome of Elbows after Resection Arthroplasty of Failed Total Elbow Replacement.

Background: Recovery of elbow function is a challenging problem following resection arthroplasty after failure of total elbow prosthesis. The objective of this study is to evaluate long term functional outcome in a series of such patients.

Materials And Methods: Nineteen patients with twenty elbows who had failed total elbow arthroplasty (TEA) following the use of Baksi total elbow prosthesis needed removal of prosthesis during the period from 1978 to 2003.

Ni-Catalyzed Reductive Dicarbofunctionalization of Nonactivated Alkenes: Scope and Mechanistic Insights.

Olefins devoid of directing or activating groups have been dicarbofunctionalized here with two electrophilic carbon sources under reductive conditions. Simultaneous formation of one C(sp)-C(sp) and one C(sp)-C(sp) bond across a variety of unbiased π-systems proceeds with exquisite selectivity by the combination of a Ni catalyst with TDAE as sacrificial reductant. Control experiments and computational studies revealed the feasibility of a radical-based mechanism involving, formally, two interconnected Ni(I)/Ni(III) processes and demonstrated the different ability of Ni(I) species (Ni(I)I vs PhNi(I)) to reduce the C(sp)-I bond.

Dual Photoredox/Nickel-Catalyzed Three-Component Carbofunctionalization of Alkenes.

The potential of merging photoredox and nickel catalysis to perform multicomponent alkene difunctionalizations under visible-light irradiation is demonstrated here. Secondary and tertiary alkyl groups, as well as sulfonyl moieties can be added to the terminal position of the double bond with simultaneous arylation of the internal carbon atom in a single step under mild reaction conditions. The process, devoid of stoichiometric additives, benefits from the use of bench-stable and easy-to-handle reagents, is operationally simple, and tolerates a wide variety of functional groups.

Palladium-Catalyzed Directed meta-Selective C-H Allylation of Arenes: Unactivated Internal Olefins as Allyl Surrogates.

Palladium(II)-catalyzed meta-selective C-H allylation of arenes has been developed utilizing synthetically inert unactivated acyclic internal olefins as allylic surrogates. The strong σ-donating and π-accepting ability of pyrimidine-based directing group facilitates the olefin insertion by overcoming inertness of the typical unactivated internal olefins. Exclusive allyl over styrenyl product selectivity as well as E stereoselectivity were achieved with broad substrate scope, wide functional-group tolerance, and good to excellent yields.

Simultaneous determination and risk assessment of fipronil and its metabolites in sugarcane, using GC-ECD and confirmation by GC-MS/MS.

A sensitive gas chromatographic method using a modified QuEChERS technique is reported for simultaneous determination, dissipation and risk assessment of fipronil and its metabolites in sugarcane and soil. Recoveries were 80.7-98.

A randomized, open labeled study comparing the serum levels of cobalamin after three doses of 500 mcg vs. a single dose methylcobalamin of 1500 mcg in patients with peripheral neuropathy.

Background: Vitamin B12 deficiency has been associated with peripheral neuropathy, loss of sensation in the peripheral nerves, and weakness in the lower extremities. Methylcobalamin is the most effective analogue of vitamin B12 used to treat or prevent the complications associated with vitamin B12 deficiency. The current study aimed to compare the serum cobalamin levels after administration of two different regimes of methylcobalamin in peripheral neuropathy patients.

GC-MS/MS determination and ecological risk assessment of pesticides in aquatic system: A case study in Hooghly River basin in West Bengal, India.

A liquid-liquid extraction (LLE) for water and modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for sediment combined with gas chromatography-tandem mass spectrometry (GC-MS/MS) detection in multiple reaction monitoring (MRM) mode was standardized for determination of 31 pesticides. Performance characteristics for the selected pesticides were acceptable according to European Commission's (EC) guidelines for method validation (recovery 70-120%, RSD <20% and R value ≥ 0.99).

Remote meta-C-H Cyanation of Arenes Enabled by a Pyrimidine-Based Auxiliary.

An easily removable pyrimidine-based auxiliary has been employed for the remote meta-C-H cyanation of arenes. The scope of this Pd-catalyzed cyanation reaction using copper(I) cyanide as the cyanating agent was demonstrated with benzylsilanes, benzylsulfonates, benzylphophonates, phenethylsulfonates, and phenethyl ether derivatives. The method was utilized for the synthesis of pharmaceutically valuable precursors.

Validation of Multiresidue Method for Analysis of 31 Pesticides in Rice Using Gas Chromatography-Tandem Mass Spectrometry.

Five modified QuEChERS were tested for the multiresidue analysis of 31 pesticides in rice. Rice was spiked with mixture solution of pesticides at 10 ng/g. Method selection was based on the LODs (sensitivity) and recovery tests (accuracy) of the pesticides.

Rhodium-Catalyzed meta-C-H Functionalization of Arenes.

Rhodium-catalyzed ortho-C-H functionalization is well known in the literature. Described herein is the Xphos-supported rhodium catalysis of meta-C-H olefination of benzylsulfonic acid and phenyl acetic acid frameworks with the assistance of a para-methoxy-substituted cyano phenol as the directing group. Complete mono-selectivity is observed for both scaffolds.

Validation of Multiresidue Method for Analysis of 31 Pesticides in Rice Using Gas Chromatography-Tandem Mass Spectrometry.

Five modified QuEChERS were tested for the multiresidue analysis of 31 pesticides in rice. Rice was spiked with mixturesolution of pesticides at 10 ng/g. Method selection was based on the LODs (sensitivity) and recovery tests (accuracy) of the pesticides.

Persistence of acetamiprid in paddy and soil under West Bengal agro-climatic conditions.

Acetamiprid insecticide has been widely used to control paddy insects. In order to find out the dissipation of acetamiprid residues in paddy (variety: Satabdi), field studies were conducted in Nadia, West Bengal. Acetamiprid (20% SP) was applied twice at 10 g (T), 20 g (T) and 40 g (T) a.

Template-Assisted meta-C-H Alkylation and Alkenylation of Arenes.

To expand the scope of meta-functionalization, a pyrimidine-based template effective for the formation of β-aryl aldehydes and ketones, using allyl alcohols, by meta-C-H activation of benzylsulfonyl esters is described. In addition, α,β-unsaturated aldehydes were generated by in situ olefination and deprotection of allyl benzyl ethers. These new functionalizations at the meta-position of an arene have also been successfully implemented in benzylphosphonate, phenethyl carbonyl, and phenethylsulfonyl ester scaffolds.