Pause and play: dihydrooxazine oxides are stable intermediates that are protonated directly, without the intermediacy of the zwitterions, in organocatalytic Michael additions of aldehydes and nitroalkenes (see scheme, R=alkyl). Protonation of these species explains both the role of the acid co-catalyst in these reactions, and the observed stereochemistry when the reaction is conducted with α-alkylnitroalkenes.

Textile dyes and effluents are considered as one of the worst polluters of our priceless water sources and soils. New sources of natural pigments are getting particular research interests due to the toxicity produced by synthetic colouring agents. Plant sources are being explored extensively for natural pigments but inadequate yield of those sources hampered the progression. Apart from the enormous antibacterial applications, fungi may provide a readily available alternative source of natural pigments. Here, we isolated a fungal strain from spoiled mango which is capable of producing pigments suitable for textile dyeing. The spoiled mangoes were selected as a source of different fungi. Among them one particular fungal isolate was selected for its visible production of secondary metabolites. Molecular identification using internal transcribed spacer sequencing revealed the fungi as Talaromyces verruculosus strain. The growth and pigment production of the fungi was optimised to obtain highest yield. Extracted pigment was applied to cotton fabric following a standard dyeing procedure for natural pigment. Adequate colour yield and negative cytotoxicity result suggested that the fungi source of pigment could be a potential replacement for hazardous synthetic dyes.

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Synthesis of macrocyclic compounds including natural products with varying complexities by ring closing metathesis is described. Twelve to very large rings that have been synthesized in moderate to good yields and the synthesis of larger rings as a part of bi-or poly-cyclic systems are also described in this review. The effectiveness of the Grubbs' catalyst towards the RCM in presence of free alcohols, epoxides as well as with various silyl ethers is also presented. In addition to these, the application of RCM towards the syntheses of various naturally occurring macrolides, lactams and unnatural cyclic poly ethers, catenanes etc. are described.

A convergent, flexible, and efficient approach to the synthesis of curvularin is described. Key step is the high-yielding macrocyclic ring formation by ring-closing metathesis (RCM) using the Grubbs second-generation catalyst.

Organic solar cells (OSCs) are considered to have reached a second golden age with profoundly improved power conversion efficiency (PCE) and device stability in recent years. The modification of the interface layer plays a significant role in achieving performance enhancement in OSCs. Herein, the use of the atomic layer deposition (ALD) ultrathin TiOx to modify the interface layer in OSCs is reported. The modification with only two TiOx ALD cycles not only effectively passivates the interface between the ZnO electron transport layer (ETL) and the active layer, but also reduces the series resistance and improves the charge transport process in the device. An absolute 1% increase in PCE with enhanced device stability for modified OSCs is achieved. Semitransparent OSCs are also fabricated by applying this interface modification strategy. The modification with two TiOx ALD cycles increases the electrical device performance without affecting the optical properties of the semitransparent device. An average PCE of 10.46% with an average visible transmittance (AVT) of 19.61% and a color rendering index (CRI) close to 100 is demonstrated for the fabricated semitransparent device with the modification. The ALD‐assisted interface modification provides a straightforward way to realize high‐performance semitransparent OSCs.

Intense xenon vacuum ultraviolet (VUV) emission is observed from a high-pressure capillary cathode microdischarge in direct current operation, by superimposing a high-voltage pulse of 50ns duration. Under stagnant gas conditions, the total VUV light intensity increases linearly with pressure from 400 to 1013mbar for a fixed voltage pulse. At fixed pressure, however, the VUV light intensity increases superlinearly with voltage pulse height ranging from 08to2.8kV. Gains in emission intensity are obtained by inducing gas flow through the capillary cathode, presumably because of excimer dimer survival due to gas cooling.