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71.
72.
Vanangamudi Murugesan Nidhi Sethi Yenamandra S. Prabhakar Seturam B. Katti 《Molecular diversity》2011,15(2):457-466
The inhibition of dipeptidyl peptidase IV (DPP-IV) has emerged as an attractive target in the treatment of type 2 diabetes.
In view of this development, a critical analysis of structural requirements of the DPP-IV inhibitors is envisioned to identify
the significant features toward design of selective inhibitors. The comparative molecular field analysis (CoMFA) and comparative
molecular similarity indices analysis (CoMSIA) contour plots of pyrrolidine based analogues are used to analyze the structural
requirements of a DPP-IV active site. The CoMFA model has shown a cross-validated q
2 of 0.651 with a non-cross-validated r
2 of 0.882 and explained 70.6% variance in the activity of external test compounds. In this, the steric and electrostatic fields
have respectively contributed 59.8 and 40.2%, respectively, to the explained activity of the compounds. The CoMSIA model has
shown optimum predictivity (cross-validated q
2 = 0.661; non-cross-validated r
2 = 0.803; external test set’s predictive r
2 = 0.706) with four molecular fields namely, steric, electrostatic, hydrogen bond (HB)-donor, and HB-acceptor. The contour
plots of molecular fields resulting from these studies have suggested: (i) steric restriction with small electron rich substituent
at 2- and 3-position of pyrrolidine ring, (ii) presence of electropositive ring linker between the pyrrolidine head and aryl
tail, (iii) presence of electron-rich groups around the aryl tail moiety, and (iv) presence of sulfonamide between the ring
linker and aryl tail which would increase DPP-IV binding affinity of the compounds. These findings will help in the design
of structurally related/new compounds as potential DPP-IV inhibitors. 相似文献
73.
We obtain a solution of the DGLAP equation for the gluon at low x first by expanding the gluon in a Taylor series and then using the method of characteristics. We test its validity by comparing
it with that of Glück, Reya and Vogt. The convergence criteria of the approximation used are also discussed. We also calculate
εF
2(x,Q)2/ε In Q
2 using its approximate relations with the gluon distribution at low x. The predictions are then compared with the HERA data. 相似文献
74.
Manik Waghmare Bipin Khade Pradip Chaudhari Prabhakar Dongre 《Journal of nanoparticle research》2018,20(7):185
It is well known that when nanoparticles (NPs) are exposed to biological fluid, it results into formation of nanoparticle protein corona, which has been the subject of extensive studies for the development of targeted drug delivery. In this work, we demonstrated the dynamic light scattering, fluorescence, and UV-visible spectroscopy as quantitative and qualitative tools to monitor adsorption of BSA protein onto silver nanoparticles (AgNPs). The adsorption resulted in significant gradual increase in average hydrodynamic radius of BSA-AgNP corona from 24 to 35 nm and its attainment of equilibrium point (saturation) that correlated with albumin concentration enables condition for bound and unbound protein adsorption to be interpreted. Using DLS, the dissociation constant (KD) was obtained for soft corona to be 2.09?±?0.30 μM. The UV-visible and fluorescence spectroscopy results were correlated with DLS. Loss of percent helicity in secondary structure of adsorbed BSA was monitored in both coronas as compared to native protein. Both coronas were found to be biocompatible with RBC membrane. Further, the results of adsorption isotherm model were used to validate the multilayer formation of albumin protein on silver nanoparticles. The obtained results would be relevant in the drug design development for tumor-targeted therapy. 相似文献
75.
We give a Darboux transformation for the Bogoyavlensky–Konoplechenko equation, which is a two-dimensional generalisation of the Korteweg–deVries equation. This transformation is used to construct a family of solutions of this equation. 相似文献
76.
Prabhakar P. Singh 《Solid State Communications》2003,125(6):323-326
We present a comparison of electron-phonon interaction in NbB2 and MgB2, calculated using full-potential, density-functional-based methods in P6/mmm crystal structure. Our results, described in terms of (i) electronic structure, (ii) phonon density of states F(ω), (iii) Eliashberg function α2F(ω), and (iv) the solutions of the isotropic Eliashberg gap equation, clearly show significant differences in the electron-phonon interaction in NbB2 and MgB2. We find that the average electron-phonon coupling constant λ is equal to 0.59 for MgB2 and 0.43 for NbB2, leading to superconducting transition temperatures Tc at around 22 K for MgB2 and 3 K for NbB2. 相似文献
77.
78.
Thiophene and its substituted derivatives are very important class of heterocyclic compounds which shows interesting applications in the field of medicinal chemistry. It has made an indispensable anchor for medicinal chemists to produce combinatorial library and carry out exhaustive efforts in the search of lead molecules. It has been reported to possess a wide range of therapeutic properties with diverse applications in medicinal chemistry and material science, attracting great interest in industry as well as academia. It has been proven to be effectual drugs in present respective disease scenario. They are remarkably effective compounds both with respect to their biological and physiological functions such as anti-inflammatory, anti-psychotic, anti-arrhythmic, anti-anxiety, anti-fungal, antioxidant, estrogen receptor modulating, anti-mitotic, anti-microbial, kinases inhibiting and anti-cancer. Thus the synthesis and characterization of novel thiophene moieties with wider therapeutic activity is a topic of interest for the medicinal chemist to synthesize and investigate new structural prototypes with more effective pharmacological activity. However, several commercially available drugs such as Tipepidine, Tiquizium Bromides, Timepidium Bromide, Dorzolamide, Tioconazole, Citizolam, Sertaconazole Nitrate and Benocyclidine also contain thiophene nucleus. Therefore, it seems to be a requirement to collect recent information in order to understand the current status of the thiophene nucleus in medicinal chemistry research. 相似文献
79.
80.