Novel s-triazine compounds are disclosed that have a formula represented by the following: L1, L2, L3, R1, R2, R3, R4, R5a, R5b, and R5c are as described herein. The compounds may be prepared as pharmaceutical compositions, and may be used for the prevention and treatment of a variety of conditions in mammals including humans, where microbial infection is either a direct cause or a related condition.