Metal ions associated with amyloid-β (Aβ) species have been suggested to be involved in neurodegeneration leading to the progression of Alzheimer's disease (AD). The role of metal-involved Aβ species in AD neuropathogenesis, however, is not fully elucidated. In order to advance this understanding and contribute to the therapeutic development for AD, the rational structure-based design of small molecules that specifically target metal ions surrounded by Aβ species has recently received increased attention. To date, only a few compounds have been fashioned for this purpose. Herein, we report the design strategy, synthesis, characterization, and reactivity of new bifunctional IMPY derivatives K1 and K2. Using UV-vis and high-resolution two-dimensional (2D) NMR spectroscopy, the bifunctionality of K1 and K2 (metal chelation and Aβ interaction) was confirmed. These bifunctional IMPY derivatives showed preferential reactivity toward metal-induced Aβ aggregation over metal-free conditions in both in vitro inhibition and disaggregation experiments. Taken together, this study provides another example of a bifunctional small molecule framework that can target metal ions associated with Aβ species.

Alkyds that are formulated from an identical chemical composition will exhibit different properties and performance depending on the preparation process. In general, alkyds can be prepared from two processes, i.e., alcoholysis (monoglyceride) or fatty acid. Fatty acid process is chosen in this study as the preparation process of alkyd resin. In this process, it involves a step-by-step addition of material to complete the esterification at 180-250 ºC. In addition, synthesis of alkyd can be carried out without solvent (fusion cook) or with solvent (solvent cook). Nowadays, the concern about emission of volatile organic compounds lead to reduction or elimination of solvents as base of industry materials in order to produce more environmental friendly products. In this project, three different alkyd resins namely alk-45, alk-47 and alk-65 were successfully synthesized under fatty acid process by employing without solvent technique. The prepared resins were characterized by FTIR, NMR, TGA, GPC and DSC instruments. Other physical tests such as acid number, hydroxyl number, moisture content were also performed.

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Alpha-chloro ynones have been reduced using Noyori's Ru catalyst to furnish alpha-chloro propargylic alcohols with excellent enantioselectivity. These have been used as a common precursor for the preparation of (E)- and (Z)-2-hydroxy-3,4-unsaturated disubstituted sulfilimines. The latter serve as precursors for the highly regio- and stereoselective preparation of bromo carbamates.

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