Leone, Marilisa, et al. Chemical Biology & Drug Design 77.1 (2011): 12-19.
"Cyclo-DEYDDPfK; Cyclo-DE(pY)LDPfK; Cyclo-DE(FCOOH)LDPfK (FCOOH= phenylalanine with a carboxyl group at the para position) were purchased either from the MCW facility of the Wisconsin Medical College or from CPC Scientific (San José, CA, USA)"
