This report describes the discovery of a new generation of tetracycline antibacterial agents, the “glycylcyclines”. These agents are notable for their activity against a broad spectrum of tetracyclinesusceptible and-resistant Gram-negative and Gram-positive aerobic and anaerobic bacteria possessing various classes of tetracycline-resistant determinants [tet B (efflux), tet M (ribosomal protection)]. The design and synthesis of a number of 7- ...