Synthesis of 6-hydroxy-N-(6-methylpyridin-2-yl) naphthalene-2- carboxamide and its alkoxy analogues

6-hydroxy-N-(6-methylpyridin-2-yl)naphthalene-2- carboxamide and its alkoxy analogues bearing long alkyl chains have been synthesized using 6-hydroxy-2-naphthoic acid and 2-amino-6-picoline. The facile synthetic scheme reported here using conventional laboratory reagents opens up a new strategy for the generation of libraries of such compounds in high yields. The H-bond donor acceptor groups along with the reactive 2-naphthol moiety present in the target compounds make them useful for their use in self-assembly and self-replication studies.

Study of Antioxidant Property of the Rhizome Extract of Polygonatum cirrhifolium (Mahameda) and its use in the green synthesis of Gold nanoparticles

The antioxidant efficacy of the rhizome extract of Polygonatum cirrhifolium (Mahameda) has been studied against a stable 2, 2-diphenylpicrylhydrazyl (DPPH) radical at room temperature. The chemical constituents present in the rhizome extract have been utilized for the one step synthesis of stable gold nanoparticles at room temperature under very mild conditions.

A bioactive diterpene; Nasimalun A from Croton oblongifolius Roxb.

A clerodane type diterpene, nasimalun A was isolated from a dichloromethane extract of the leaves of Croton oblongifolius Roxb. Nasimalun A showed moderate cytotoxicity toward MOLT- 3 cell line with IC50 value of 26.44 µg/mL. Furthermore, nasimalun A showed minimum inhibitory concentration (MIC) of 50, 12.5, and100 μg/mL for Bacillus cereus and both Staphylococcus aureus, and Staphylococcus epidermidis respectively.

Study of Antioxidant Property of the Endosperm Extract of Borassus flabellifer (Taal) and its use in the green synthesis of Gold nanoparticles

The antioxidant activity of the endosperm extract of Borassus flabellifer (commonly known as Taal) has been studied against a long lived 2,2-diphenylpicrylhydrazyl (DPPH) radical at room temperature. The phytochemicals present in the endosperm extract have been utilized for the synthesis of stable gold nanoparticles at room temperature under very mild conditions. The synthesized gold nanoparticles were characterized by Surface Plasmon Resonance spectroscopy, High resolution transmission electron microscopy, X-Ray diffraction and FTIR studies and a mechanism for the synthesis of stabilized gold nanoparticles has been proposed.

Self-assembly study of ammonium oleanolate and generation of gel– gold nanoparticle hybrid material

A solution of oleanolic acid, a renewable nano-sized monohydroxy triterpenic acid in tetrahydrofuran, transformed into a gel instantly at room temperature on treatment with aqueous ammonia. Study of the self-assembly properties of ammonium oleanolate in water and aqueous solvent mixtures indicated that it self-assembles in the aqueous solvent mixtures forming gels in DMSO-water and DMF-water. Fibrillar networks with optical birefringence properties were observed by polarized optical microscopy. Scanning electron microscopy of the dried gel samples indicated fibrillar networks with fibers of nano to micrometer diameters. The thermodynamic parameters calculated from the gel to sol transition temperatures indicated the stability of the gels. A gel-gold nanoparticles hybrid material has also been prepared and characterized by HRTEM, EDX, SAED and surface Plasmon resonance studies.

Temperature Dependent Magnetic Susceptibility and Equilibrium Studies in Solution: Evans’s Method

The chemical shift in a solvent caused by the presence of a paramagnetic species and the temperature dependence of the chemical shift difference to determine the temperature dependent magnetic susceptibility can be studied using Evans method. The method is very useful because a common NMR instrument, easily accessible in a department of chemistry, allows the accurate measurement of paramagnetic susceptibilities. The present review highlights planar (S = 0) and octahedral (S = 1) forms of Ni(II) complexes are in equilibrium and has been followed in the temperature range 298 − 338 K by 1H NMR technique using the protocol of Evans’s method.

Synthetic studies of antascomicin A: Construction of C1-C16 fragment

This communication describes the stereoselective synthesis of C1-C16 fragment of antascomicin A, a non-immunosuppressive immunophil-binding natural product. Evans aldol reaction was used extensively to install all the stereo centres present in the fragment. The hemikatel present in the fragment was synthesized via DMP-mediated oxidation of β-hydroxy amide followed by acid catalyzed hemiketalization.

Glucocorticoid receptor: A potent cellular & gene therapy target for cancer and cancer stem cells

Glucocorticoid receptor (GR) is expressed in the cytoplasm of almost all cells, if not all of cancer and non-cancer cells. Moreover, unlike many other factors implicated with cancer, it is neither overexpressed nor is it expressed on cell-membrane surface to qualify logically as a viable target for treating cancer. GR is importantly linked with alternate pathway of energy metabolism in cancer cells and our research indicated that cancer cells possibly tend to avoid activation of GR which would have otherwise instigate that energy demanding alternate pathway called gluconeogenesis. We discovered a way to induce cancer cell-selective GR-transactivation which leads to among many things, gluconeogenesis, reversal of epithelial-to-mesenchymal transition (EMT), drug- sensitization in drug-resistant cancer cells etc. Thus, we proved, although it warrants further studies, that GR in cancer cells behave differently and hence it can be a viable target for the treatment of cancer.

External-stimuli responsiveness of self-assembled supramolecular architectures

Supramolecular materials are dynamic in nature which can reversibly dissociate and associate, deconstruct and reconstruct in response to external stimulus. These adaptive supramolecular materials are the materials of future which have shown a new path towards the chemistry of advanced and complex matter. In recent years these supramolecular materials are in the centre of attraction due to its wide range of applications in diversified fields like drug delivery, nanoelectronics, shape memory devices etc. In this short review, the supramolecular assembly-disassembly of molecules in response to the various external stimuli such as pH, light, redox, enzyme have been discussed which were developed in recent past.

Synthetic Methods for Novel Benzofuran Derivatives and their Biological Activities

Benzofuran is the heterocyclic compound consisting of fused benzene and furan rings. The benzofuran moiety is widely distributed in both natural and artificial molecules. Substituted benzofurans are pharmaceutically important heterocycles that display numerous biological activities such as antimicrobial, antifungal, antiHIV, anticancer, antimalarial, anti-inflammatory activities. Some derivatives of benzofurans are also used as organic materials due to their optical and electronic properties. Owing to their broad spectrum applications, it is of great significance to develop systematic and novel approaches to benzofurans. During the past decades, many synthetic efforts have been devoted so far to the synthesis of benzofuran derivatives. The present review highlights the recently synthesized benzofurans and their biological activities.