A compound of Formula or a salt thereof: wherein: X is 0, S, Se, or NR n, where R n is H or C 1-6 alkyl; R is H, halo, -CN, -NR A R B, -C(=O)NR A R B, or -N(R A)C(=O)R B, in which R A and R B are each independently selected from hydrogen, C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 3-7 carbocyclyl C 6-10 aryl, 5-10 membered heteroaryl, and 3-10 membered heterocyclyl, -OH,, -NO 2, -SO 3 H, -SO 2 NH 2, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted alkoxy, optionally substituted aminoalkyl, optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, or optionally substituted heteroaryl; R 1 is H, halo, -CN, -CO 2 H, NR A R B, -C(=O)NR A R B, or -N(R A)C(=O)R B, in which R A and R B are each independently selected from hydrogen, C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 3-7 carbocyclyl C 6-10 aryl, 5-10 membered heteroaryl, and 3-10 membered heterocyclyl, -OH, -NO 2, -SO 3 H, -SO 2 NH 2, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted alkoxy, optionally substituted aminoalkyl, optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, or optionally substituted heteroaryl; R 2 and R 4 are each independently H, halo, -CN, -CO 2 H, NR A R B, -C(=O)NR A R B, or - N(R A)C(=O)R B, in which R A and R B are each independently selected from hydrogen, C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 3-7 carbocyclyl C 6-10 aryl, 5-10 membered heteroaryl, and 3-10 membered heterocyclyl, -OH, -NO 2, -SO 3 H, -SO 2 NH 2, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted alkoxy, optionally substituted aminoalkyl, optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, or optionally substituted heteroaryl; R 3 is C 2-6 alkyl substituted with -CO 2 H or SO 3 H, or optionally substituted heterocyclyl; each R 5 is independently halo, -CN, -CO 2 H, NR A R B, -C(=O)NR A R B, or -N(R A)C(=O)R B, in which R A and R B are each independently selected from hydrogen, C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 3-7 carbocyclyl C 6-10 aryl, 5-10 membered heteroaryl, and 3-10 membered heterocyclyl, -OH, -NO 2, -SO 3 H, -SO 2 NH 2, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted alkoxy, optionally substituted aminoalkyl, optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, or optionally substituted heteroaryl; and m is 0, 1, 2, 3, or 4. X is 0, S, Se, or NR n, where R n is H or C 1-6 alkyl; R is H, halo, -CN, -NR A R B, -C(=O)NR A R B, or -N(R A)C(=O)R B, in which R A and R B are each independently selected from hydrogen, C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 3-7 carbocyclyl C 6-10 aryl, 5-10 membered heteroaryl, and 3-10 membered heterocyclyl, -OH,, -NO 2, -SO 3 H, -SO 2 NH 2, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted alkoxy, optionally substituted aminoalkyl, optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, or optionally substituted heteroaryl; R 1 is H, halo, -CN, -CO 2 H, NR A R B, -C(=O)NR A R B, or -N(R A)C(=O)R B, in which R A and R B are each independently selected from hydrogen, C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 3-7 carbocyclyl C 6-10 aryl, 5-10 membered heteroaryl, and 3-10 membered heterocyclyl, -OH, -NO 2, -SO 3 H, -SO 2 NH 2, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted alkoxy, optionally substituted aminoalkyl, optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, or optionally substituted heteroaryl; R 2 and R 4 are each independently H, halo, -CN, -CO 2 H, NR A R B, -C(=O)NR A R B, or - N(R A)C(=O)R B, in which R A and R B are each independently selected from hydrogen, C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 3-7 carbocyclyl C 6-10 aryl, 5-10 membered heteroaryl, and 3-10 membered heterocyclyl, -OH, -NO 2, -SO 3 H, -SO 2 NH 2, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted alkoxy, optionally substituted aminoalkyl, optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, or optionally substituted heteroaryl; R 3 is C 2-6 alkyl substituted with -CO 2 H or SO 3 H, or optionally substituted heterocyclyl; each R 5 is independently halo, -CN, -CO 2 H, NR A R B, -C(=O)NR A R B, or -N(R A)C(=O)R B, in which R A and R B are each independently selected from hydrogen, C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 3-7 carbocyclyl C 6-10 aryl, 5-10 membered heteroaryl, and 3-10 membered heterocyclyl, -OH, -NO 2, -SO 3 H, -SO 2 NH 2, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted alkoxy, optionally substituted aminoalkyl, optionally substituted carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, or optionally substituted heteroaryl; and m is 0, 1, 2, 3, or 4.