Table 1: Sequences of constrained human parathyroid hormone peptides.

PeptideEC50 (nM)

hPTH-(1-31)NH2 (1)19.9
Leu27 cyclo(Glu22-Lys26)-hPTH-(1-31)-NH2 (2)3.3
cyclo(Lys18-Asp22)[Ala1, Nle8, Lys18, Asp22, Leu27]hPTH(1-31)NH2 (3)0.29
bicyclo(Lys18-Asp22, Lys26-Asp30)[Ala1, Nle8, Lys18, Asp22, Leu27]hPTH(1-31)NH2 (4)0.13
tricyclo(Lys13-Asp17, Lys18-Asp22, Lys26-Asp30) Ala1, Nle8, Lys18, , Leu27 hPTH 1-31 NH2  (5)0.14
, Nal23, Tyr34 bPTH 1-34 -NH2 (6)0.85
, , Nal23, Tyr34 bPTH(1-34)-NH2 (7)0.2