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Environmentally acceptable and renewably sourced flame retardants are in demand. Recent studies have shown that the incorporation of the biopolymer lignin into a polymer can improve its ability to form a char layer upon heating to a high temperature. Char layer formation is a central component of flame-retardant activity. The covalent modification of lignin is an established technique that is being applied to the development of potential flame retardants. In this study, four novel modified lignins were prepared, and their char-forming abilities were assessed using thermogravimetric analysis. The lignin was obtained from date palm wood using a butanosolv pretreatment. The removal of the majority of the ester groups from this heavily acylated lignin was achieved via alkaline hydrolysis. The subsequent modification of the lignin involved the incorporation of an azide functional group and copper-catalysed azide–alkyne cycloaddition reactions. These reactions enabled novel organophosphorus heterocycles to be linked to the lignin. Our preliminary results suggest that the modified lignins had improved char-forming activity compared to the controls. 31P and HSQC NMR and small-molecule X-ray crystallography were used to analyse the prepared compounds and lignins. [ABSTRACT FROM AUTHOR]

The yeast three-hybrid (Y3H) approach shows considerable promise for the unbiased identification of novel small molecule-protein interactions. In recent years, it has been successfully used to link a number of bioactive molecules to novel protein binding partners. However despite its potential importance as a protein target identification method, the Y3H technique has not yet been widely adopted, in part due to the challenges associated with the synthesis of the complex chemical inducers of dimerisation (CIDs). The development of a modular approach using potentially "off the shelf" synthetic components was achieved and allowed the synthesis of a family of four triazole-containing CIDs, MTX-Cmpd2.2-2.5. These CIDs were then compared using the Y3H approach with three of them giving a strong positive interaction with a known target of compound 2, TgCDPK1. These results showed that the modular nature of our synthetic strategy may help to overcome the challenges currently encountered with CID synthesis and should contribute to the Y3H approach reaching its full potential as an unbiased target identification strategy. [ABSTRACT FROM AUTHOR]

The search for potent and selective sirtuin inhibitors continues as chemical tools of this type are of use in helping to assign the function of this interesting class of deacetylases. Here we describe SAR studies starting from the unselective sirtuin inhibitor tenovin-6. These studies identify a sub-micromolar inhibitor that has increased selectivity for SIRT2 over SIRT1 compared to tenovin-6. In addition, a 1H-NMR-based method is developed and used to validate further this class of sirtuin inhibitors. A thermal shift analysis of SIRT2 in the presence of tenovin-6, -43, a control tenovin and the known SIRT2 inhibitor AGK2 is also presented. [ABSTRACT FROM AUTHOR]