Polyelectrolyte Complexes: A Review of their Applicability in Drug Delivery Technology

Over the past several years, great advances have been made towards novel drug delivery systems. The phenomena of interpolymer interactions and formation of polyelectrolyte complexes have been the focus of intensive fundamental and applied research. Interpolyelectrolyte complexes combine unique physicochemical properties with high biocompatibility. Studies have been carried out on many different polymer blends and types. Such combinations may possess unique properties that are different from those of individual component. The present review emphasizes on the applicability of polyelectrolyte complexes in drug delivery technology

Synthesis of β‑<i>C</i>‑Galactosyl Ceramide and Its New Aza Variant via the Horner–Wadsworth–Emmons Reaction

A simple strategy for the synthesis of β-<i>C</i>-galactosyl ceramide and its new aza-variant analogue is described using the Horner–Wadsworth–Emmons reaction as the key step in combining the sugar and aglycone portions

Pseudopyronine B: A Potent Antimicrobial and Anticancer Molecule Isolated from a Pseudomonas mosselii

In continuation of our search for new bioactive compounds from soil microbes, a fluorescent Pseudomonas strain isolated from paddy field soil of Kuttanad, Kerala, India was screened for the production of bioactive secondary metabolites. This strain was identified as Pseudomonas mosselii through 16S rDNA gene sequencing followed by BLAST analysis and the bioactive metabolites produced were purified by column chromatography (silica gel) and a pure bioactive secondary metabolite was isolated. This bioactive compound was identified as Pseudopyronine B by NMR and HR-ESI-MS. Pseudopyronine B recorded significant antimicrobial activity especially against Gram-positive bacteria and agriculturally important fungi. MTT assay was used for finding cell proliferation inhibition, and Pseudopyronine B recorded significant antitumor activity against non-small cell lung cancer cell (A549), and mouse melanoma cell (B16F10). The preliminary MTT assay results revealed that Pseudopyronine B recorded both dose- and time-dependent inhibition of the growth of test cancer cell lines. Pseudopyronine B induced apoptotic cell death in cancer cells as evidenced by Acridine orange/ethidium bromide and Hoechst staining, and this was further confirmed by flow cytometry analysis using Annexin V. Cell cycle analysis also supports apoptosis by inducing G2/M accumulation in both A549 and B16F10 cells. Pseudopyronine B treated cells recorded significant up-regulation of caspase 3 activity. Moreover, this compound recorded immunomodulatory activity by enhancing the proliferation of lymphocytes. The production of Pseudopyronine B by P. mosselii and its anticancer activity in A549 and B16F10 cell lines is reported here for the first time. The present study has a substantial influence on the information of Pseudopyronine B from P. mosselii as potential sources of novel drug molecule for the pharmaceutical companies, especially as potent antimicrobial and anticancer agent

Metal-Free Multiple Carbon–Carbon and Carbon–Hydrogen Bond Activations via Charge-Switching Mechanism in Unstrained Diindolylmethanes

A transformation of the unstrained phenol substituted 3,3′-diindolyl­methanes (DIPMs) to 2,3′-diindolylketones (DIKs) by double C–C single bond cleavage with associated rearrangements, triggered by phenyliodine­(III) diacetate (PIDA), is reported. Density functional theory studies reveal a mechanism involving multiple “charge-switching” steps by synergistic involvement of the two indole units with overall low activation energy. The indole ‘charge-switching’ mechanism in DIPMs was further extended toward synthesis of a natural product motif cyclohepta­[<i>b</i>]­indole from biaryl appended DIBM