Table 1.

Antibacterial activity of 2, 4, and conjugate 6 against MRSA strains.^{a, b}

Test organism					MIC/IC50 ± SEM, μg/mL
	2	4	6	PA	C5-Curc- PA	Methc	Ciprod
MRSA (ATCC 43300)	250/111.3 ± 10.8	7.8/5.1 ± 0.1	62.5/39.5 ± 1.9	>1000	>1000	1.95/0.98 ± 0.02	0.50/0.20 ± 0.09
CIMRSA 1	250/141.0 ± 12.4	7.8/4.2 ± 0.1	62.5/30.3 ± 2.1	>1000	>1000	7.8/2.2 ± 0.7	15.6/10.4 ± 3.7
CIMRSA 2	250/133.4 ± 15.8	7.8/5.0 ± 0.5	62.5/34.9 ± 1.6	>1000	>1000	31.3/11.8 ± 3.9/7.3	3.9/2.9 ± 1.2
CIMRSA 3	250/123.8 ± 26.2	15.6/6.3 ± 0.2	62.5/34.2 ± 1.0	>1000	>1000	3.9/2.2 ± 0.7	7.8/4.4± 0.8
CIMRSA 4	500/184.9 ± 8.2	15.6/6.5 ± 0.1	31.3/24.9 ± 1.5	>1000	>1000	31.3/11.8 ± 3.9	3.9/2.0 ± 0.2
CIMRSA 5	500/202.4 ± 24.5	7.8/5.1 ± 0.2	31.3/25.4 ± 1.0	>1000	>1000	3.9/1.9 ± 0.4	15.6/5.3 ± 0.5
CIMRSA 6	500/194.7 ± 29.4	7.8/5.7 ± 0.8	62.5/38.9 ± 1.6	>1000	>1000	1.9/1.2 ± 0.1	7.8/2.5 ± 0.2
CIMRSA 7	500/303.1 ± 33.6	7.8/4.7 ± 0.3	62.5/34.2 ± 0.4	>1000	>1000	3.9/1.3 ± 0.2	0.98/0.39 ± 0.04
E. coli (ATCC 25922)	>1,000	>1,000	>1,000	>1000	>1000	>1,000	<0.008

^aExperiments were performed in triplicate (N =3).

^bCIMRSA = Clinical isolate of methicillin-resistant S. aureus. CIMRSA stains were kindly donated by a community hospital in San Juan, Puerto Rico.

^cMeth = Methicillin. Positive control.

^dCipro = Ciprofloxacin. Positive control.