Troleandomycin (also known Triacetyl-oleandomycin and having brand name Tao) is a macrolide antibiotic which used to for the treat of infections of the upper and lower respiratory tract: such as tonsillitis, bronchitis, sinusitis, and pneumonia. However, the brand name Tao was discontinued. Troleandomycin acts by penetrating the bacterial cell membrane and reversibly binding to the 50 S subunit of bacterial ribosomes or near the "P" or donor site so that binding of tRNA (transfer RNA) to the donor site is blocked. Translocation of peptides from the "A" or acceptor site to the "P" or donor site is prevented, and subsequent protein synthesis is inhibited.