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Using a bidentate ligand, a Schiff base of 5-acetamido-1,3,4- thiadiazole-2-sulphonamide, complexes of transition metals having the general formula ML2, where M = Mn(II), Fe(II), Ni(II) and Cu(II), were synthesized. The complexes were characterized by elemental analysis, molar conductivity, magnetic moment, electronic, ESR and IR spectroscopy, and particle size analysis. The conductivity data of the complexes suggests their non-electrolytic nature. The stability constants and free energy change for the complexes were calculated. Spectral studies and magnetic susceptibility measurements revealed an octahedral geometry for all the complexes. The ligand and its complexes were screened for their fungicidal activity against Aspergillus niger and A. flavus

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In this paper we study oriented bipartite graphs. In particular, we introduce bitransitive graphs and bitournaments. Several characterizations of bitransitive bitournaments are obtained. Next we prove the Caccetta-Häggkvist Conjecture for oriented bipartite graphs for some cases for which it is unsolved in general. We introduce the concept of oriented odd-even graphs and (undirected) odd-even graphs and characterize (oriented) bipartite graphs in terms of them.In fact, we show that any (oriented) bipartite graph can be represented by some (oriented) odd-even graph. We obtain some conditions for connectedness of odd-even graphs. Finally we introduce Goldbach graphs which are special type of odd-even graphs. We show that the famous Goldbach's conjecture is equivalent to the connectedness of Goldbach graphs. Several other related conjectures are related to various parameters of Goldbach graphs. We study nature of degrees of vertices and independent sets of Goldbach graphs.

Gastrointestinal stromal tumors (GISTs) are the most common Mesenchymal Neoplasm of the gastrointestinal tract. The tumorigenesis of GISTs has been associated with the gain-of-function mutation and abnormal activation of the stem cell factor receptor (c-KIT) and platelet-derived growth factor receptor alpha (PDGFRα) kinases. Hence, inhibitors that target c-KIT and PDGFRα could be a therapeutic option for the treatment of GISTs. The available approved c-KIT/PDGFRα inhibitors possessed low efficacy with off-target effects, which necessitated the development of potent inhibitors. We performed computational studies of 48 pyrazolopyridine derivatives that showed inhibitory activity against c-KIT and PDGFRα to study the structural properties important for inhibition of both the kinases. The derivative of phenylurea, which has high activities for both c-KIT (pIC50 = 8.6) and PDGFRα (pIC50 = 8.1), was used as the representative compound for the dataset. Molecular docking and molecular dynamics simulation (100 ns) of compound 14 was performed. Compound 14 showed the formation of hydrogen bonding with Cys673, Glu640, and Asp810 in c-KIT, and Cys677, Glu644, and Asp836 in PDGFRα. The results also suggested that Thr670/T674 substitution in c-KIT/PDGFRα induced conformational changes at the binding site of the receptors. Three-dimensional quantitative structure–activity relationship (3D-QSAR) models were developed based on the inhibitors. Contour map analysis showed that electropositive and bulky substituents at the para-position and the meta-position of the benzyl ring of compound 14 was favorable and may increase the inhibitory activity against both c-KIT and PDGFRα. Analysis of the results suggested that having bulky and hydrophobic substituents that extend into the hydrophobic pocket of the binding site increases the activity for both c-KIT and PDGFRα. Based on the contour map analysis, 50 compounds were designed, and the activities were predicted. An evaluation of binding free energy showed that eight of the designed compounds have potential binding affinity with c-KIT/PDGFRα. Absorption, distribution, metabolism, excretion and toxicity (ADMET) and synthetic feasibility tests showed that the designed compounds have reasonable pharmaceutical properties and synthetic feasibility. Further experimental study of the designed compounds is recommended. The structural information from this study could provide useful insight into the future development of c-KIT and PDGFRα inhibitors.

Owing to the limitations of conventional therapies, there has been an increasing need for nanomedicines for real-time diagnosis and effective treatment of life-threatening diseases. Despite the conceptual and technological success achieved by researchers worldwide, the complexities of biological systems, efficient engineering and formulation of monodispersed nanomedicines, inadequate information on bio–nano interactions, issues on health hazards, clinical trials and commercialization have set new challenges in biomedical research. This review highlights how the biological membrane improves the performance of nanomedicines in drug delivery. With the list of nanomedicines getting longer gradually to overcome the drawbacks of conventional therapeutics, it is important to concentrate on the interactions between nanostructures and living systems in order to improve the biocompatibility and therapeutic efficacy of functional nanomedicines.