A compound having the following structure: or a stereoisomer, pharmaceutically acceptable salt, wherein: Q 1 is hydrogen, or Q 2 is hydrogen, optionally substituted aryl, optionally substituted aralkyl, optionally substituted cycloalkyl, optionally substituted cycloalkylalkyl, optionally substituted heterocyclyl, optionally substituted heterocyclylalkyl, optionally substituted, heteroaryl, optionally substituted heteroarylalkyl, -C(=NH)NR 4 R 5, (CR 10 R 11) p R 12, or Q 3 is hydrogen, optionally substituted aryl, optionally substituted aralkyl, optionally substituted cycloalkyl, optionally substituted cycloalkylalkyl, optionally substituted heterocyclyl, optionally substituted heterocyclylalkyl, optionally substituted heteroaryl, optionally substituted heteroarylalkyl, -C(=NH)NR 4 R 5, (CR 10 R 11) p R 12, or each R 1, R 2, R 3, R 4, R 5, R 8 and R 10 is, independently, hydrogen or C 1 -C 6 alkyl, or R 1 and R 2 together with the atoms to which they are attached can form a heterocyclic ring having from 4 to 6 ring atoms, or R 2 and R 3 together with the atoms to which they are attached can form a heterocyclic ring having from 4 to 6 ring atoms, or R 1 and R 3 together with the atoms to which they are attached can form a carbocyclic ring having from 4 to 6 ring atoms, or R 4 and R 5 together with the atom to which they are attached can form a heterocyclic ring having from 4 to 6 ring atoms; each R 6 and R 7 is, independently, hydrogen, hydroxyl, amino or C 1 -C 6 alkyl, or R 6 and R 7 together with the atoms to which they are attached can form a heterocyclic ring having from 4 to 6 ring atoms; each R 9 is, independently, hydrogen or methyl; each R 11 is, independently, hydrogen, hydroxyl, amino or C 1 -C 6 alkyl; each R 12 is, independently, hydroxyl or amino; each n is, independently, an integer from 0 to 4; each m is, independently, an integer from 0 to 4; and each p is, independently, an integer from 1 to 5, and wherein (i) at least two of Q 1, Q 2 and Q 3 are other than hydrogen, and (ii) if Q 1 is hydrogen, then at least one of Q 2 and Q 3 is -C(=NH)NR 4 R 5. wherein: Q 1 is hydrogen, or Q 2 is hydrogen, optionally substituted aryl, optionally substituted aralkyl, optionally substituted cycloalkyl, optionally substituted cycloalkylalkyl, optionally substituted heterocyclyl, optionally substituted heterocyclylalkyl, optionally substituted, heteroaryl, optionally substituted heteroarylalkyl, -C(=NH)NR 4 R 5, (CR 10 R 11) p R 12, or Q 3 is hydrogen, optionally substituted aryl, optionally substituted aralkyl, optionally substituted cycloalkyl, optionally substituted cycloalkylalkyl, optionally substituted heterocyclyl, optionally substituted heterocyclylalkyl, optionally substituted heteroaryl, optionally substituted heteroarylalkyl, -C(=NH)NR 4 R 5, (CR 10 R 11) p R 12, or each R 1, R 2, R 3, R 4, R 5, R 8 and R 10 is, independently, hydrogen or C 1 -C 6 alkyl, or R 1 and R 2 together with the atoms to which they are attached can form a heterocyclic ring having from 4 to 6 ring atoms, or R 2 and R 3 together with the atoms to which they are attached can form a heterocyclic ring having from 4 to 6 ring atoms, or R 1 and R 3 together with the atoms to which they are attached can form a carbocyclic ring having from 4 to 6 ring atoms, or R 4 and R 5 together with the atom to which they are attached can form a heterocyclic ring having from 4 to 6 ring atoms; each R 6 and R 7 is, independently, hydrogen, hydroxyl, amino or C 1 -C 6 alkyl, or R 6 and R 7 together with the atoms to which they are attached can form a heterocyclic ring having from 4 to 6 ring atoms; each R 9 is, independently, hydrogen or methyl; each R 11 is, independently, hydrogen, hydroxyl, amino or C 1 -C 6 alkyl; each R 12 is, independently, hydroxyl or amino; each n is, independently, an integer from 0 to 4; each m is, independently, an integer from 0 to 4; and each p is, independently, an integer from 1 to 5, and wherein (i) at least two of Q 1, Q 2 and Q 3 are other than hydrogen, and (ii) if Q 1 is hydrogen, then at least one of Q 2 and Q 3 is -C(=NH)NR 4 R 5. each R 1, R 2, R 3, R 4, R 5, R 8 and R 10 is, independently, hydrogen or C 1 -C 6 alkyl, or R 1 and R 2 together with the atoms to which they are attached can form a heterocyclic ring having from 4 to 6 ring atoms, or R 2 and R 3 together with the atoms to which they are attached can form a heterocyclic ring having from 4 to 6 ring atoms, or R 1 and R 3 together with the atoms to which they are attached can form a carbocyclic ring having from 4 to 6 ring atoms, or R 4 and R 5 together with the atom to which they are attached can form a heterocyclic ring having from 4 to 6 ring atoms; each R 6 and R 7 is, independently, hydrogen, hydroxyl, amino or C 1 -C 6 alkyl, or R 6 and R 7 together with the atoms to which they are attached can form a heterocyclic ring having from 4 to 6 ring atoms; each R 9 is, independently, hydrogen or methyl; each R 11 is, independently, hydrogen, hydroxyl, amino or C 1 -C 6 alkyl; each R 12 is, independently, hydroxyl or amino; each n is, independently, an integer from 0 to 4; each m is, independently, an integer from 0 to 4; and each p is, independently, an integer from 1 to 5, and wherein (i) at least two of Q 1, Q 2 and Q 3 are other than hydrogen, and (ii) if Q 1 is hydrogen, then at least one of Q 2 and Q 3 is -C(=NH)NR 4 R 5.