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51.
Seema Thakral A. K. Madan 《Journal of inclusion phenomena and macrocyclic chemistry》2008,60(3-4):203-209
In the present study, urea, a well-known adductor for linear compounds was successfully utilized for inclusion of glipizide—a
highly substituted cyclic organic compound through a modified technique. Formation of glipizide co-inclusion compounds in
urea was confirmed by FTIR, DSC and XRD. The minimum proportion of rapidly adductible endocyte (RAE) required for adduction
of glipizide in urea was estimated by a modified Zimmerschied calorimetric method. Urea–GLP–RAE inclusion compounds containing
varying proportions of guests were prepared and their thermal behaviour studied by DSC. The co-inclusion compounds were found
to exhibit good content uniformity. Through the formation of co-inclusion compounds of urea, it was possible to achieve steep
improvement in the dissolution efficiency of glipizide, which is a BCS class II drug. 相似文献
52.
Rajendra N. Goyal Neena Jain Vibha Gurnani 《Monatshefte für Chemie / Chemical Monthly》2001,132(5):575-585
Summary. The electrochemical behaviour of chlorpromazine has been examined in phosphate buffers in aqueous as well as micellar media
at a pyrolytic graphite electrode surface. Two oxidation peaks were obtained in linear sweep voltammetry of chlorpromazine.
The first peak corresponds to the formation of the cationic free radical, which on further 1e−-oxidation gives a dication. The spectroscopic changes and kinetics of the cationic free radical and dication species generated
during electrooxidation of chlorpromazine were investigated in both media. The decay of the dication was studied chronoamperometrically
and was found to follow first-order kinetics with a half-life of ∼25 ms. Surfactants affect both E
p and i
p values. The anionic surfactant SDS has been found to catalyze the reaction of the free radical cation and the dication. 相似文献
53.
Here we investigate a majorization problem involving starlike function of complex order belonging to a certain class defined by means of fractional derivatives. Relevant connections of the main results obtained in this paper with those given by earlier workers on the subject are also pointed out. 相似文献
54.
55.
A. K. Goyal 《Periodica Mathematica Hungarica》1986,17(1):13-20
In this paper,D-strong and almostD-strong near-rings have been defined. It has been proved that ifR is aD-strongS-near ring, then prime ideals, strictly prime ideals and completely prime ideals coincide. Also ifR is aD-strong near-ring with identity, then every maximal right ideal becomes a maximal ideal and moreover every 2-primitive near-ring becomes a near-field. Several properties, chain conditions and structure theorems have also been discussed.Most of the parts of this paper are included in author's doctoral dissertation at Sukhadia University Udaipur (1983). The author expresses his gratitude to Dr.S. C. Choudhary for his kind guidance. 相似文献
56.
Mirza Saqib Baig Ashutosh Kumar Mohammad Imran Siddiqi Neena Goyal 《Journal of computer-aided molecular design》2010,24(1):77-87
Leishmania donovani dipeptidylcarboxypeptidsae (LdDCP), an angiotensin converting enzyme (ACE) related metallopeptidase has been identified and
characterized as a putative drug target for antileishmanial chemotherapy. The kinetic parameters for LdDCP with substrate,
Hip-His-Leu were determined as, Km, 4 mM and Vmax, 1.173 μmole/ml/min. Inhibition studies revealed that known ACE inhibitors
(captopril and bradykinin potentiating peptide; BPP1) were weak inhibitors for LdDCP as compared to human testicular ACE (htACE)
with Ki values of 35.8 nM and 3.9 μM, respectively. Three dimensional model of LdDCP was generated based on crystal structure
of Escherichia coli DCP (EcDCP) by means of comparative modeling and assessed using PROSAII, PROCHECK and WHATIF. Captopril docking with htACE,
LdDCP and EcDCP and analysis of molecular electrostatic potentials (MEP) suggested that the active site domain of three enzymes
has several minor but potentially important structural differences. These differences could be exploited for designing selective
inhibitor of LdDCP thereby antileishmanial compounds either by denovo drug design or virtual screening of small molecule databases. 相似文献
57.
Idris Mohd Srivastava Seema Baggi Tulsidas R. Shukla Sudhir Kumar 《平面色谱法杂志一现代薄层色谱法》2010,23(5):339-342
JPC – Journal of Planar Chromatography – Modern TLC - A simple, accurate, and inexpensive high-performance thin-layer chromatography (HPTLC) method has been established for analysis of... 相似文献
58.
A rapid and semi-quantitative immunochromatographic strip (ICS) test for cortisol analysis in serum was developed. The test strip was based on a competitive assay format. Colloidal gold nanoparticles were synthesized and coupled with cortisol-3-carboxymethyloxime-adipic acid dihydrazide-bovine serum albumin (F-3-CMO-ADH-BSA) antigen to directly compete with cortisol in human serum samples. F-3-CMO-ADH-BSA-gold label and uncoupled colloidal gold nanoparticles were appropriately characterized using UV-vis spectroscopy, transmission electron microscopy and atomic force microscopy. Anticortisol antibody raised against F-3-CMO-BSA immunogen in New Zealand white rabbits was coated on the NC membrane as test line. Anti-BSA antibody was used as control line. The lower detection limit of the ICS test was 30 ngmL(-1) with visual detection and was completed in 10 min. About 30 human serum samples were also analyzed by the developed strip test and their range of cortisol concentration was established. The developed ICS test is rapid, economic and user friendly. 相似文献
59.
Carbohydrate-based low molecular weight gelators are an interesting class of molecules with many potential applications. Previously, we have found that certain esters and carbamates of 4,6-O-benzylidene-α-d-methyl-glucopyranoside are low molecular weight gelators for a variety of solvents, including water. In order to obtain effective and robust sugar-based organogelators and understand the structure and gelation relationship, we extended our studies using 4,6-O-benzylidene-α-d-methyl-2-deoxy-2-amino-glucopyranoside as the headgroup. A series of amides and ureas were prepared from the protected d-glucosamine and the corresponding isocyanates or acid chlorides, in good yields. The self-assembling properties of these compounds were studied in several solvents, including water and aqueous solutions. Comparing to the ester and carbamate derivatives previously prepared from d-glucose, the amides and urea derivatives afforded more robust gels at lower concentrations typically. Most of these compounds were found to be efficient low molecular weight hydrogelators (LMHGs) for aqueous solutions at concentrations lower than 0.5 wt %. The preparation and characterization of these compounds are reported here. 相似文献
60.
Sambasivarao Kotha Vittal Seema Kuldeep Singh Kodand Dinkar Deodhar 《Tetrahedron letters》2010,51(17):2301-421
Highly functionalized cage compounds have been prepared via cross-metathesis (CM) using Grubbs modified N-tolyl catalyst 7. A strategic utilization of photo-thermal metathesis and catalytic metathesis sequence for the synthesis of functionalized caged molecules has been demonstrated. 相似文献