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101.
The effect of the added fluoroquinolone, Ciprofloxacin Hydrochloride (CpH), on structural properties of Bovine Serum Albumin (BSA) was investigated by Circular Dichroism (CD), steady-state, time-resolved and Dynamic Light Scattering (DLS) spectroscopic approaches. The intrinsic fluorescence of the Tryptophan (Trp) amino acid residue in the globular protein BSA was made use of and the effect of pH at two different temperatures was thoroughly investigated. CD results indicate that CpH induces some structural changes in BSA and this has been well-supported by steady-state, lifetime and DLS data. The fluorescence intensity of Trp gradually decreases with the rise in concentration of CpH and we have conclusively proved that at pH 7.4 and 9.2, the mechanism of fluorescence quenching is mostly dynamic in nature, whereas at pH 4.5 mainly static quenching is operational. Thermodynamic parameters have been studied to rationalize the nature of binding of CpH to BSA, and we have concluded that hydrophobic and van der Waals forces play an important role in the process of drug-protein interaction at three different pH values. The lifetime of Trp was found to decrease with the rise in CpH concentration and the percentage reduction in lifetime was found to be a function of the pH of the medium under investigation. 相似文献
102.
The first enantiospecific synthesis of (-)-parvifoline, employing ring-closing metathesis as the key step, and (-)-curcuquinone from naturally occurring (R)-(+)-citronellal is described. 相似文献
103.
A new effective approach to the synthesis of some new (Z)-5-(substituted)-2-thioxothiazolidin-4-one 3a–l and (Z)-5-(substituted)-2-(methylthio)thiazol-4(5H)-one 5a–l is reported under microwave irradiation as well as conventional conditions. 相似文献
104.
Polymer‐Supported Sulfonic Acid‐Catalyzed Candid Synthesis and Photophysical Properties of 2H‐indazolo[2,1‐b]phthalazinetriones 下载免费PDF全文
Abhijeet Mulik Dattatraya Chandam Prasad Patil Dayanand Patil Suryabala Jagdale Sandip Sankpal Madhukar Deshmukh 《Journal of heterocyclic chemistry》2015,52(3):931-937
Polystyrene‐supported sulfonic acid has been found to be an efficient catalyst for the one‐pot, three‐component synthesis of 2H‐indazolo[2,1‐b]phthalazinetriones in greener solvent glycerol. Use of greener solvent glycerol along with a polymer‐supported, low toxic, and inexpensive catalyst renders the method eco‐friendly. High yields, simple product isolation procedure, and fluorescent and electroluminescent natures of the products are the noteworthy aspects of this protocol. 相似文献
105.
Uttam K. Tambar 《Tetrahedron letters》2007,48(3):345-350
A palladium-catalyzed tandem Stille-oxa-electrocyclization reaction has been developed for the convergent preparation of highly substituted polycyclic pyran systems. The strategy presented in this letter is an alternative to the known methods for constructing similar pyran systems. The substrate scope of this diastereoselective transformation is explored. 相似文献
106.
An efficient solvent-free synthesis of various 2,4,5-triaryl imidazoles and 1,2,4,5-tetraaryl imidazoles has been developed using silica chloride as a heterogeneous catalyst. The present methodology offers several advantages, such as excellent yields, shorter reaction times, economic availability, and reusability of catalyst. 相似文献
107.
Shrutisagar Dattatraya Haveli Sudipta Roy Vibha Gautam Ketan C. Parmar Srinivasan Chandrasekaran 《Tetrahedron》2013,69(52):11138-11143
NIS/NaN3 mediated ring opening of various donor–acceptor cyclopropanes has been investigated. The study shows the necessity of the donor oxygen lone pair in such ring opening reactions. This methodology has been utilized in the synthesis of C-1 linked pseudodisaccharides through the use of click chemistry. 相似文献
108.
The primary ammonium monocarboxylate (PAM) synthon has been exploited to generate a new series of PAM salts from the free amine of L ‐phenylalanine‐3‐pyridyl amide, (S)‐2‐amino‐3‐phenyl‐N‐(pyridine‐3‐yl)propanamine (designated as “ B ”), and various substituted benzoic acids (designated as “ A(R) ”; R =4‐Me, 4‐Cl, 4‐Br, 4‐NO2, 3‐Me, 3‐Cl, 3‐Br, 3‐NO2, 2‐Me, 2‐Cl, 2‐Br, 2‐NO2). The 4‐ and 3‐substituted benzoate salts showed moderate‐to‐excellent gelation ability with a number of polar and apolar solvents. The gels were characterized by DSC, rheology, SEM and TEM, FTIR spectroscopy, etc. Structure–property studies based on single‐crystal powder X‐ray diffraction (PXRD) and FTIR data provided insights into the role of the PAM synthon in the formation of the gel networks. Interestingly, some of the gels were capable of forming and stabilizing gold nanoparticles at room temperature without the use of any exogenous reducing agents. 相似文献
109.
Patil Rupesh C. Patil Uttam P. Jagdale Ashutosh A. Shinde Sachinkumar K. Patil Suresh S. 《Research on Chemical Intermediates》2020,46(7):3527-3543
Research on Chemical Intermediates - α,α′-bis(substituted benzylidene)cycloalkanones were efficiently prepared from variously substituted aldehydes and cycloalkanones in water by... 相似文献
110.
Relativistic state‐specific multireference perturbation theory incorporating improved virtual orbitals: Application to the ground state single‐bond dissociation 下载免费PDF全文