A practical synthesis of the pseudotripeptide RC-1291

Organic Process Research and Development

Volumn 10, Issue 2, 2006, Pages 339-345

  Paul, Bernhard J ^a   Littler, Benjamin J ^a   Jos, Frederic ^a   Vogt, Paul F ^a   Pines, Seemon H ^b  

^a ALBANY MOLECULAR RESEARCH INC   (United States)

^b Sapphire Therapeutics Inc   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 33645540275     PISSN: 10836160     EISSN: None     Source Type: Journal    
DOI: 10.1021/op0502506     Document Type: Article

References (13)

1. Ankersen, M. U.S. Patent 6,576,648 B2, 2003.
2. Kern, K. A.; Norton, J. A. J. Parenteral Enteral Nutr. 1988, 12, 286.
3. For the synthesis of the Boc-protected precursor of hydrazide 3, see: Garcia-Rubio, S.; Wilson, C. D.; Renner, D. A.; Rosser, J. O.; Patra, D.; Reid, J. G.; Pines, S. H. Org. Process Res. Dev. 2004, 8, 360.
4. For a comparison of the effectiveness and safety of several catalysts (including HOAt) for promoting imidazolide couplings, see: Dunn, P. J.; Hoffmann, W.; Kang, Y.; Mitchell, J. C.; Snowden, M. J. Org. Process Res. Dev. 2005, 9, 956.
5. Humphrey, J. M.; Chamberlin, A. R. Chem. Rev. 1997, 97, 2243.
6. Because the impurity was easily removed during the subsequent recrystallization and because of the time constraints of having to deliver material for the preclinical and clinical evaluation of RC-1291, characterization of this impurity was not performed.
7. (a) König, W.; Geiger, R. Chem. Ber. 1970,103,788.
8. (b) König, W.; Geiger, R. Chem. Ber. 1970, 103, 2024.
9. (c) Carpino, L. A.; El-Faham, A. J. Org. Chem. 1995, 60, 3561.
10. (a) Millbanks, C. In Encyclopedia of Reagents for Organic Synthesis; Paquette, L. A., Ed.; Wiley: New York, 1995; p 4336.
11. (b) Schwarz, M. Synlett 2000, 9, 1369.
12. Initial work for the crystallization of RC-1291 was performed by SSCI, Inc., West Lafayette, IN.
13. Crude 7 from a 1.81 mol and a 0.1 mol scale coupling reaction was combined for the deprotection.