A lincosamide antibiotic; active against Gram-positive bacteria, including various strains of S. pneumoniae, S. viridans, S. aureus, and S. epidermidis (MICs = 0.002-0.1, 0.005-0.2, 0.04-1.6, and 0.1-0.2 UG/ml, respectively); active against chloroquine-resistant and -sensitive strains of P. falciparum (IC50s = 3.12 and 8.81 nM, respectively); inhibits bacterial protein synthesis by interacting with the 50S ribosome; increases survival in a mouse model of a secondary S. pneumoniae infection at 15 mg/kg twice daily for seven days