An atom-economic N-to-C-directed solid-phasepeptidesynthesis is reported that uses benzyl (Bn) or (benzhydryl-carbamoyl)-methyl (BcM) esters of amino acids as the building blocks, which facilitate efficient hydrazinolysis, convenient conversion to acyl azide, and robust amidation with the next amino acid ester. This method is free of coupling reagents and free of protection on the side-chain OH,
据报道,一种原子经济的 N 到 C 定向的固相肽合成,使用氨基酸的苄基 (Bn) 或 (二苯甲基-氨基甲酰基)-甲基 (BcM) 酯作为构建单元,促进高效肼解,方便转化为酰基叠氮化物,并与下一个氨基酸酯进行稳健的酰胺化。该方法无需偶联试剂,对侧链OH、CO 2 H、CONH2等无保护,因此与基于BOC或Fmoc的C-to-N-相比,原子经济性显着提高定向方法。
Cross-Claisen Condensation of<i>N</i>-Fmoc-Amino Acids - A Short Route to Heterocyclic γ-Amino Acids
作者:Loïc Mathieu、Clément Bonnel、Nicolas Masurier、Ludovic T. Maillard、Jean Martinez、Vincent Lisowski
DOI:10.1002/ejoc.201500012
日期:2015.4
cross-Claisen condensations between N-Fmoc-amino acids and sterically hindered 1,1-dimethylallyl acetate. The optimized conditions are compatible with aliphatic, aromatic, acidic, and basic amino acids. The resulting N-Fmoc-β-keto ester intermediates were engaged in a two-step process to give ATCs in 45–90 % yields. The synthetic protocol provides a highly flexible method for the introduction of a wide variety
The present invention provides a protecting reagent that can be removed in a high yield even under acidic conditions and can afford a resulting product at a high purity in an organic synthesis reaction such as peptide synthesis and the like. The inventive protecting reagent is particular benzylic compound having only one hydroxyl group substituted by an organic group having an aliphatic hydrocarbon group having a carbon number of not less than 14.
The present invention provides a protecting reagent that can be removed in a high yield even under acidic conditions and can afford a resulting product at a high purity in an organic synthesis reaction such as peptide synthesis and the like. The inventive protecting reagent is particular benzylic compound having only one hydroxyl group substituted by an organic group having an aliphatic hydrocarbon group having a carbon number of not less than 14.
Pd−C-Induced Catalytic Transfer Hydrogenation with Triethylsilane
作者:Pijus K. Mandal、John S. McMurray
DOI:10.1021/jo0706123
日期:2007.8.1
In situ generation of molecular hydrogen by addition of triethylsilane to palladium-charcoal catalyst results in rapid and efficient reduction of multiple bonds, azides, imines, and nitro groups, as well as benzyl group and allyl group deprotection under mild, neutral conditions.