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CoS@MorphcdtH NPs and CoS@4‐MPipzcdtH NPs were synthesized by precipitation method involving three mechanisms: inclusion, occlusion, and adsorption. The synthesized NPs were characterized with the help of UV‐Vis spectroscopy, FESEM‐EDAX, powder x‐ray diffraction, TEM, ESIMS, TG/DSC analysis. The morphology of the CoS@MorphcdtH NPs and CoS@4‐MPipzcdtH NPs were hexagonal and rectangular, and the particles were in the range 7–12 nm. UV–visible spectral measurements showed surface plasmon resonance at 320 nm–340 nm with band gap of 3.65 eV–3.86 eV. The catalytically active CoSNPs called were investigated for the reduction of 4‐nitrophenol (4‐NP) via hydrogenation using sodium borohydride (NaBH4) as a reducing agent. Both the CoS NPs successfully reduced 4‐NP to 4‐ aminophenol (4‐AP) in a short time, catalytic performances are almost unchanged for the first five cycles. Herein, we report the preparation and characterizations of efficient active CoS NPs consisting carbodithioic acid framework as a support/capping material, along with catalytic property. [ABSTRACT FROM AUTHOR]

The interactions of diglycine with sulphathiazole drug as a function of temperatures have been studied using volumetric and acoustic parameters. Densities and speeds of sound of diglycine in (0.001, 0.002, 0.005 and 0.010) mol·kg-1 aqueous solutions of sulphathiazole drug have been measured at five different temperatures of (288.15, 293.15, 298.15, 303.15 and 308.15) K under 0.1 MPa pressure. From density data, the apparent molar volume, the partial molar volume and the standard partial molar volume of transfer for glycine from water to aqueous sulphathiazole solutions have been calculated. Partial molar isentropic compression and partial molar isentropic compression of transfer have been calculated from the speed of sound data. Transfer parameters by using cosphere overlap model have been explained on the basis of ionic-hydrophilic, hydrophilic-hydrophilic, hydrophilic-hydrophobic and hydrophobic-hydrophobic group interactions. To draw the conclusion from the volumetric and acoustic data, limiting apparent molar expansion as well as the hydration numbers have been studied. The calculated values of thermal expansion coefficient have small and positive values. All of these derived or calculated parameters are explained to understand the solvation behaviour and various types of interactions born in the ternary solutions of (dipeptide + drug + water) due to change in structure. We have also attempted to examine the temperature and concentration dependence of such interactions. [ABSTRACT FROM AUTHOR]

The densities (ρ) and speeds of sound (u) for glycine in aqueous solutions of (0.01, 0.02, 0.03, and 0.04) mol·kg-1 sulphathiazole drug have been measured at T = (288.15, 293.15, 298.15, 303.15 and 308.15) K, using vibrating tube digital densimeter and sound analyser Anton-Paar Model DSA - 5000. The apparent molar properties like apparent molar volume (vφ), apparent molar adiabatic compressibility (Kφ, s) and the apparent molar volume (Vφ 0) and adiabatic compressibility at infinite dilution (Kφ, s 0) of glycine have been determined in water as well as in ternary mixtures containing sulphathiazole drug at different concentrations and at different temperatures from experimental data of densities and speeds of sound under atmospheric pressure. These data were also used to calculate the transfer parameters. Transfer parameters have been explained from the point of view of concentration dependence of solute-solute and solute-solvent interactions. The limiting apparent molar expansibility (Eφ°) values for glycine in aqueous solutions of drug have been calculated. The calculated values of thermal expansion coefficient (α2) have small and positive values. These results are explained on the basis of drug-amino acid - water interactions and hydrophobic-hydrophilic interactions. [ABSTRACT FROM AUTHOR]

Significant attention has been given to organotin (IV) amino acids compounds in recent years. Organometallic compounds are better known for their potentiality to stabilize peculiar stereochemistry of their complexes and application in agriculture, catalysis and as single source precursors. Due to the better stability and diverse molecular structures the complexes own a wide range of biological activities. These individual properties create an alliance of action in the hybrid complex. In this review, we discuss the chemistry of organotin (IV) complexes and their different aspects in various fields. The aim of the present review is to evaluate the synthesis, characterization and biological activities of organotin compounds. [ABSTRACT FROM AUTHOR]

The spectral characteristics of different drugs i.e. sulfanilamide, sulfanilic acid, sulfosalicylic acid dihydrate (SSAD) and sulfamethoxazole in aqueous α-cyclodextrin (CD) have been investigated at neutral pH. The formation of inclusion complexes of sulfa drugs with α-CD leads to the changes in fluorescence and absorption spectra which further enable the calculation of association constant of the bind processes by implementing the non-linear regression on the experimental data. The standard Gibbs energy ΔG was also calculated for the systems in which complex formation was observed. The α-CD study indicates that the sulpha drugs form 1:1 inclusion complex with α-CD. [ABSTRACT FROM AUTHOR]

Abstract: Herein we report an expeditious and facile sonochemical synthesis method that takes just a few minutes to produce organic‐inorganic hybrid nanoflowers and their application as a nanobiocatalyst. Surfactant treated Burkholderia cepacia lipase was used as the organic component and manganese sulfate as the inorganic component to synthesize the nanoflowers in less than 10 minutes. Careful investigation of the process parameters was performed to obtain the optimized value for each attribute viz. sonication time (7.5 min), lipase concentration (0.1 mg/mL), MnSO4 concentration (150 mM), sonication frequency (33 kHz) and pH (8.0). An additional post‐synthesis treatment of nanoflowers with N‐hydroxysuccinimide (NHS) increased their reusability to over nine cycles with an overall six‐fold increase in the activity. In addition, thermal stability was demonstrated through a twenty‐fold increase in the half‐life of immobilized lipase at 80 °C than in free form. The hybrid nanoflowers displayed a marked improvement in the kinetic resolution of racemic intermediates of metoprolol, a selective β‐1 blocker drug [C (%)=46.7, eep=96.5, E=156] and cloranolol, a non‐selective β‐blocker drug [C (%)=49.5, eep=96.0, E=157] compared to free lipase which signifies its importance as a nanobiocatalyst. [ABSTRACT FROM AUTHOR]

Abstract: The present study exhibits a facile method for the expeditious synthesis of organic‐inorganic hybrid nanoassemblies. Pseudomonas fluorescens lipase was immobilized on the nanoassembly and its application as a nanobiocatalyst was demonstrated. Scanning electron microscopy analysis depicted petal‐like morphology of the newly synthesized hybrid. The sonochemical method screened as a faster route for the synthesis of hybrid nanopetals with a marked increase in enzyme activity (15 folds). Furthermore, an additional treatment of the hybrid nanopetals with chemical modifiers likes 1‐ethyl‐3‐(3‐dimethylaminopropyl)‐carbodiimide (EDC) exhibited improved stability and reusability upto six cycles. A systematic investigation of the reaction parameters influencing the formation of lipase‐embedded hybrid nanopetals was done. In addition, the nanobiocatalytic potential of hybrid nanopetals was explored in the kinetic resolution of racemic secondary alcohols. [ABSTRACT FROM AUTHOR]

A profoundly time-efficient chemoenzymatic method for the synthesis of ( S) -3-(4-chlorophenoxy)propan-1,2-diol and ( S) -1-chloro-3-(2,5-dichlorophenoxy)propan-2-ol, two important pharmaceutical intermediates, was successfully developed using Pseudomonas fluorescens lipase (PFL). Kinetic resolution was successfully achieved using vinyl acetate as acylating agent, toluene/hexane as solvent, and reaction temperature of 30°C giving high enantioselectivity and conversion. Under optimized condition, PFL demonstrated 50.2% conversion, enantiomeric excess of 95.0%, enantioselectivity (E = 153) in an optimum time of 1 hour and 50.3% conversion, enantiomeric excess of 95.2%, enantioselectivity (E = 161) in an optimum time of 3 hours, for the two racemic alcohols, respectively. Docking of the R- and S-enantiomers of the intermediates demonstrated stronger H-bond interaction between the hydroxyl group of the R-enantiomer and the key binding residues of the catalytic site of the lipase, while the S-enantiomer demonstrated lesser interaction. Thus, docking study complemented the experimental outcome that PFL preferentially acylated the R form of the intermediates. The present study demonstrates a cost-effective and expeditious biocatalytic process that can be applied in the enantiopure synthesis of pharmaceutical intermediates and drugs. [ABSTRACT FROM AUTHOR]

Solid-state fermentation using the microfungus Penicillium brevicompactum for the production of mycophenolic acid is reported in this paper. Of the initial substrates tested (whole wheat, cracked wheat, long grain Basmati rice, and short grain Parmal rice), Parmal rice proved to be the best. Under initial conditions, using steamed Parmal rice with 80% ( w/ w) initial moisture content, a maximum mycophenolic acid concentration of 3.4 g/kg substrate was achieved in 12 days of fermentation at 25 °C. The above substrate was supplemented with the following additional nutrients (g/L packed substrate): glucose 40.0, peptone 54.0, KHPO 8.0, MgSO4⋅7HO 2.0, glycine 7.0, and methionine 1.65 (initial pH 5.0). A small amount of a specified trace element solution was also added. The final mycophenolic acid concentration was increased to nearly 4 g/kg substrate by replacing glucose with molasses. Replacing Parmal rice with rice bran as substrate further improved the mycophenolic acid production to nearly 4.5 g/kg substrate. [ABSTRACT FROM AUTHOR]

Lidocaine HCl and procaine HCl are local anesthetics widely used in minor chirurgic procedures; nevertheless, spectral information about their behavior is not complete at present. In this context, in this paper, absorbance and fluorescence studies of both the drugs with α- and β-cyclodextrins (CDs) have been measured at 298.15 K. The thermodynamic parameters: binding constant ( K) and standard state Gibbs energy (∆ G°) were calculated for the systems in which complex formation was observed. The α- and β-CD study indicates that the lidocaine HCl and procaine HCl drugs form 1:1 inclusion complex with α- and β-CD. Both experimental and theoretical studies revealed that the phenyl ring with the amide group of the drug is encapsulated in the hydrophobic CD cavity. van der Waals interactions are mainly responsible for complex formation of lidocaine hydrochloride and procaine hydrochloride with CDs. [ABSTRACT FROM AUTHOR]

The interaction of diglycine with sulphamethoxazole drug as a function of temperature and concentration have been investigated by volumetric method. The density of ternary mixture of diglycine (0.002-0.01 mol • kg-1) in aqueous sulphamethoxazole drug (0.001-0.01 mol • kg-1) solution have been measured using Anton Paar DSA 5000 instrument at T = (288.15 to 308.15) K. The apparent molar volumes Vφ, partialmolar volume at infinite dilution V0φ, transfer partial molar volume ΔtrV0φ, partialmolar expansibility E02, thermal expansion coefficient α2, and Hepler's constant (∂C∞P/∂P)T are calculated from density data. The above parameters are used to interpret the solute-solute and solute-solvent interactions of diglycine in aqueous solution of sulphamethoxazole drug. Hydration number and interaction coefficients have also been calculated from these data. Dehydration of diglycine is observed, rising with the temperature and drugmolality. These results are explained on the basis of drug-water-amino acid interactions. The data suggest that interaction between ions and charged/hydrophilic groups are predominant. [ABSTRACT FROM AUTHOR]