L-Alanine,L-alanyl-L-alanyl-L-alanyl-L-alanyl-L-alanyl-L-alanyl-L-alanyl-L-alanyl-L-alanyl-L-alanyl-L-alanyl-L-alanyl-L-alanyl-L-alanyl-L-alanyl-, phenylmethyl ester,mono(trifluoroacetate)