Efficient synthesis of N-protected amino/peptide Weinreb amides from T3P and DBU

Synthesis and cytotoxic activity of novel A-ring cleaved ursolic acid derivatives in human non-small cell lung cancer cells

“…% in THF) was used to prepare several amide derivatives ( 9–17 ) and the nitrile derivative ( 8 ) (Scheme 2). T3P is an efficient coupling reagent that has been employed for the conversion of carboxylic acids to aldehydes and amides, amides to nitriles, and formamides to isonitriles, as well as for the synthesis of heterocycles, Weinreb amides, β-lactams, hydroxamic acids, acyl azides, esters, imidazopyridines, and dihydropyrimidinones [38–40]. The free carboxylic acid group of compound 6 , in the presence of T3P (50 wt.…”

An Efficient and Epimerization Free Synthesis of C-Terminal Arylamides Derived from α-Amino Acids and Peptide Acids via T3P Activation

“…Recently we demonstrated efficient applications of T3P for a range of amino acid, peptide derivatives i.e. N a -protected amino or peptide acid derived acid azides (Basavaprabhu et al 2010), hydroxamic acids (Vasantha et al 2010), thio acids , alcohols (Nagendra et al 2012) and Weinreb amides (Sharanabai et al 2013). As part of our continuing endeavor on the application of T3P, we herein demonstrate an efficient and high yielding synthesis of N a -protected amino/peptide acid arylamides with chiral homogenity.…”

An optimized and scalable synthesis of propylphosphonic anhydride for general use

“…Diethyl propylphosphonate (6). 22 To a mixture of 17.4 g (0.73 mol) of NaH (free of mineral oil) in 100 ml of anhydrous THF was added a solution of 50.0 g (0.36 mol) of dry diethyl phosphonate (10) in 50 ml of anhydrous THF at 30-40°C, and the mixture was stirred overnight.…”

“…The organic layer was dried over anhydrous MgSO 4 and the solvents were removed under reduced pressure. Distillation of the residue gave 52.7 g (81%) of diethyl propylphosphonate (6).…”