Table 1.

In vitro binding activ ity for PLK PBD Peptides

Compound	Sequence	PLK1 PBD FP IC 50 [μM]	PLK3 PBD FP IC 50[μM]	Selectivity Index
1	LLCS[pT]PNGL	0.17 ± 0.03	>600	>17,000
2	LLCSTPNGL	>600	ND	ND
3	Ac-PLHS[pT]PNGL	0.06 ± 0.04	163.6	13,633
4	Ac-PLHS[pT]AI	0.064 ± 0.01	270.5	21,133
5	Ac-LHS[pT]AI	1.57 ± 0.47	>600	>1900
6	Ac-PLHS[pT]A	0.46 ± 0.12	>600	>6500
7	GPLATS[pT]PKNG	0.0057 ± 0.002	2.2	1928
8	GPLATS[pT]PNGL	0.011 ± 0.003	6.3	2864
9	Ac-PLHS[pT]PKNG	0.032 ± 0.012	133.8	20,906