Brevipolides are 5,6-dihydro-γ-pyrone derivatives, first reported in 2004 as the inhibitors of the chemokine receptor CCR5 and exhibiting cytotoxicity against cancer cells. Starting from the C2 symmetric diene-diol 2, ent-brevipolide H was synthesized for the first time in 11 steps. The anti-addition of the sulfur ylide to the α,β-unsaturated enones was developed to give the key cyclopropane moiety. The synthetic (-)-brevipolide H showed an IC50 value of 7.7 μM against PC-3 cells.

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Cellulose fibers in the form of microfibrillated cellulose (MFC) or cellulose nanocrystal (CNC) have been studied primarily for application as fillers or reinforcement in composite materials. As "green" issue has become the main concern of many scientists, numerous applications of cellulose fibers in polymer composites such as polypropylene [1], poly(lactic acid) [2,3], poly(vinyl alcohol) [4], polyethylene [5,6], are focusing to produce "green material" with superior properties. The main obstacle of incorporating cellulose fibers into polymer matrix is incompatibility between those two substances, which may decrease some of composite properties. Cellulose fibers are hydrophillic fibers, meanwhile some of polymer matrices show hydrophobic behavior. Some efforts had been done to overcome this barrier, such as using coupling agent or modifying cellulose fibers through chemical reaction. Cellulose derivatives with remarkable, distinctive properties superior to the original cellulose achieved by a variety of chemical modifications, such as esterification of the cellulose with various substances: plant triglycerides [7], long chain fatty acids [8], organic acids [9] or more reactive anhydrides [10,11], which are proven to improve the cellulose hydrophobicity. In 2006, Isogai's group in University of Tokyo has developed a new method to prepare completely individualized cellulose

Monosodium glutamate (MSG) was conjugated onto cellulose microfibrils (CMF) by the reaction in acetone solvent at the presence of triethylamine and paratoluene sulfonyl chloride. Results showed that the thermal decomposition of CMF-MSG slightly decreased to lower temperature decomposition confirmed by thermogravimetry analysis (TGA) after MSG was present on CMF surfaces which was confirmed by the reduction of intensity in carboxyl groups bands under infra-red spectroscopy (FTIR) observation. After drying, CMF-MSG was agglomerated, and the color of CMF after modification turned from white into light-brown. This study provides another way to modify nanocellulose with cheap and edible chemical reagent using monosodium glutamate. The modified cellulose probably could be applied in copper (Cu) detection paper kit at mining extraction.

This study is aimed to improve the preparation of uselful synthetic block (4R,5R,E)-methyl 5-(tert-butyldimethylsilyloxy)-4-hydroxyhepta-2,6-dienoate (1). This intermediate was used in the synthesis of (+)-Cladospolide D. The strategy developed by Voigtritter et al. was adopted to exploit the acceleration effect of copper (I) iodide. This compound was prepared from D-mannitol-derived dienediol (2) coupled with methyl acrylate through olefin cross-metathesis reaction in various conditions. It was found that performing the reaction in the presence of 3 mol% of CuI in refluxing diethyl ether gave the product up to 75% of yield with lower catalyst loading, i.e.: 2 mol%.