34368-52-0Relevant articles and documents
Total Synthesis of Plusbacin A3 and Its Dideoxy Derivative Using a Solvent-Dependent Diastereodivergent Joullié-Ugi Three-Component Reaction
Katsuyama, Akira,Yakushiji, Fumika,Ichikawa, Satoshi
, p. 7085 - 7101 (2018/07/15)
Full details of our synthetic studies toward plusbacin A3 (1), which is a depsipeptide with antibacterial activity, and its dideoxy derivative are described. To establish an efficient synthetic route of 1, a solvent-dependent diastereodivergent Joullié-Ugi three-component reaction (JU-3CR) was used to construct trans-Pro(3-OH) in a small number of steps. Two strategies were investigated toward the total synthesis. In the first synthetic strategy, the key steps were the trans-selective JU-3CR and a macrolactonization at the final stage of the synthesis. The JU-3CR using alkyl isocyanides in 1,1,1,3,3,3-hexafluoroisopropanol provided the trans products, and the coupling of the fragments to prepare the macrocyclization precursor proceeded smoothly. However, attempts toward the macrolactonization did not provide the desired product. Then, the second strategy that included esterification in an initial stage was investigated. Methods for constructing trans-Pro(3-OH) were examined using a convertible isocyanide, which could be converted to a carboxylic acid required for the following amidation. Ester bond formation was achieved through an intermolecular coupling using a hydroxyl-Asp derivative and the corresponding alcohol, and the amidation afforded a linear depsipeptide. The macrolactamization of the linear peptide gave the cyclic depsipeptide, and then the global deprotection accomplished the total synthesis of 1 and its dideoxy derivative.
STIMULUS-RESPONSIVE POLY(LACTIC-CO-GLYCOLIC)-BASED POLYMERS AND NANOPARTICLES FORMED THEREFROM
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Page/Page column 26, (2016/12/12)
PLGA-based polymers include pendant nucleophiles protected with photocleavable protecting groups. Upon deprotection, the polymers degrade rapidly via intramolecular cyclization into small molecules. The polymer may be formulated as a nanoparticle, with an encapsulated payload, which may be an imaging agent, a bioactive agent or a pharmaceutical agent.
SUBSTITUTED BENZAMIDE DERIVATIVES AS GLUCOKINASE (GK) ACTIVATORS
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Page/Page column 24, (2012/07/28)
The present invention relates to substituted benzamide derivatives of the general Formula I and their pharmaceutically acceptable salts, pharmaceutically acceptable solvates, enantiomers, diastereomers, prodrugs, metabolites, and polymorphs and can be use