Dihydropacidamycins having an antibacterial spectrum modified from that of the natural product pacidamycins and mureidomycins have been synthesized. Synthetic dihydropacidamycins with noteworthy antibacterial activity against wild-type and resistant Escherichia coli have been identified (MIC=4-8 microg/mL). Some dihydropacidamycins are shown to have activity against multi-resistant clinical strains of Mycobacterium tuberculosis. Compounds of this class are inhibitors of the cell wall biosynthetic enzyme, MraY.