@Article{JRM.2012.634102,
AUTHOR = {Leendert W. Schwab, Wouter M. J. Kloosterman, Jakob Konieczny, Katja Loos},
TITLE = {Papain Catalyzed Synthesis of Protected Amino Acid Amides},
JOURNAL = {Journal of Renewable Materials},
VOLUME = {1},
YEAR = {2013},
NUMBER = {1},
PAGES = {73--78},
URL = {http://www.techscience.com/jrm/v1n1/49680},
ISSN = {2164-6341},
ABSTRACT = {The papain catalyzed enzymatic synthesis of amido amines catalyzed from aromatic diamines and 
N-carbobenzyloxy (Z) protected amino acids (Gly, L-Leu, L-Phe) is described. The amides precipitate (yield 
19–47 % depending on the amino acid used) from the reaction mixture after one amide bond is formed thus 
preventing the formation of diamides in all cases. Papain retains its activity in buffers with a higher pH (9 and 
12) observable by the amide bond formation between 1,3-phenylene diamine and Z-L-Gly and Z-L-Phe. 
Aliphatic diamines (1,4-butanediamine and 1,6-hexanediamine) were used as well but amide formation could 
not be observed in buffers of pH 7, 9 or 12 due to the selectivity of papain.},
DOI = {10.7569/JRM.2012.634102}
}