Table 3.

PK inhibitory activity and antimicrobial activity of compounds with modification on the linker

Analogs	IC50a (nM)	MICb (μg/ml)	Linker	R1	R2	Substitutions
10a	21.4	2.0
25a	7.1	>64		H	H	6-Bromo
25b	2.4	>64		H	H	6,6′-Dibromo
25c	4.7	16		H	H	6,5′-Dibromo
26a	13.7	>64		CH3	H	6,6′-Dibromo
26b	27% @ 10 μM	ND		H	CH3	6,6′-Dibromo
27a	4.5	>64		H	H	6-Bromo
27b	3.9	>64		H	H	6,6′-Dibromo
27c	4.1	>64		H	H	6,5′-Dibromo
28a	6.5	>64		H	H	6,6′-Dibromo
28b	6.3	>64		H	H	6,5′-Dibromo
33a	54% @ 1 μM	>64		H	H	6,6′-Dibromo
33c	5.6	>64		H	H	6-Bromo
33d	1.8	2.0		H	H	6-Bromo
33e	2.1	>64		H	H	6-Bromo
33f	36% @ 10 μM	ND		H	H	6-Bromo
33b	28% @ 1 μM	>64		H	H	6,6′-Dibromo

^aIC₅₀ values are calculated from a triplicate 15-point titration. Alternatively the % inhibition at the highest concentration tested is presented.

^bMinimum concentration to give >98% inhibition of growth of S. aureus ATCC 29213 (single determination). Control MIC (vancomycin) is 1 μg/ml.