Pseudobase benzo[c]phenanthridines and the pharmaceutically acceptable salts thereof of Formula Iare provided herein. The variables R, R1, R2, R3, and R4 are defined herein. Certain pseudobase benzo[c]phenanthridines provided herein act as prodrugs, targeting the parent benzo[c]phenanthridinium alkaloid to hydrophilic or hydrophobic regions in the body. Pharmaceutical compositions comprising a pseudobase benzo[c]phenanthridine and a carrier, excipient, or diluent are provided herein. Methods of treating or preventing microbial, fungal and or viral infections and methods of treating diseases and disorders responsive to protein kinase C modulation, topoisomerase I, and/or topoisomerase II modulation are also provided.