P. Hermann, I. Lukeš, B. Máca, M. Buděšínský:
"Phosphonodipeptides, Synthesis by HOBt/DCC Method, Mass Spectra of the Protected and 1H NMR of the Unprotected Phosphonodipeptides."
Phosphorus, Sulfur, Silicon, Rel. Elements  79, (1993) 43-53



Abstract:

Phosphonodipeptides H-X-NHCHR1PO3H2 (X = Gly, Ala, Leu, Phe, R1 = H, Me) were prepd. by the active ester method using N-hydroxybenzotriazole and DCC.  Fragmentation in electron ionization mass spectra of protected phosphonodipeptides has been proposed.  Results from 1H NMR have shown slightly larger magnetic nonequivalence of CH2 protons and larger differences in NMR parameters between diastereoisomers than in common dipeptides.