811432-66-3

Upstream product

• 483368-24-7 tert-butyl {(1S)-1-[bis(4-fluorophenyl)methyl]-2-[(2S)-cyano-(4S)-fluoro-1-pyrrolidinyl]-2-oxoethyl}carbamate 
• 104-15-4 toluene-4-sulfonic acid 
• 481055-29-2 (S)-2-((tert-butoxycarbonyl)amino)-3,3-bis(4-fluorophenyl)propanoic acid 
• 483366-11-6 (2S,4S)-4-fluoropyrrolidine-2-carbonitrile; 4-methylbenzene-1-sulfonic acid 

Relevant academic research and scientific papers

Development of a practical large-scale synthesis of denagliptin tosylate

A large-scale synthesis of denagliptin tosylate has been developed. The efficiency of the synthesis has been improved from the initially scaled route by changing the order of steps (performing a dehydration at a late stage). The key step of the synthesis is a single-step peptide coupling/dehydration, mediated by n-propanephosphonic acid cyclic anhydride. The challenges of developing this synthesis into a robust and practical manufacturing route are described.

(2S,4S)-4-FLUORO-1-[4-FLUORO-BETA-(4-FLUOROPHENYL)-L-PHENYLALANYL]-2-PYRROLIDINECARBONITRILE P-TOLUENESULFONIC ACID SALT AND ANHYDROUS CRYSTALLINE FORMS THEREOF

The present invention includes anhydrous crystalline forms of (2S,4S)-4-fluoro-1-[4-fluoro-β-(4-fluorophenyl)-L-phenylalanyl]-2-pyrrolidinecarbonitrile p-toluenesulfonic acid salt.