Minimum inhibitory concentrations (MICs, in μg mL⁻¹) of erythromycin (1), roxithromycin (2), roxi-C₄–N₃ (6), roxi-C₄-Tz-NBD (9), and roxi-C₄-Tz-DMACA (10) against a panel of susceptible (for comparison) and resistant Streptococci, measured by broth microdilution in brain-heart infusion (BHI), n ≥ 3.

Species	Strain	Ery 1	Roxi 2	Roxi-N3 6	Roxi-NBD 9	Roxi-DMACA 10
S. pneumoniae	ATCC 33400	0.25–0.5	0.25–2	1–4	1–4	8–16
	ATCC 700677a	≥64	16–≥64	16–≥64	4–≥64	8–≥64
	ATCC 700676bc	≥64	≥64	≥64	≥64	≥64
S. pyogenes	ATCC 12344	≤0.016	≤0.016	≤0.016	0.031–0.063	0.13
	ATCC BAA-1412	≥64	≥64	≥64	≥64	≥64
	ATCC BAA-1414	0.031–0.13	1–2	0.063–1	≤0.016–0.063	1

^a erm(B)+.

^b mef(e)+.

^c5% CO₂.