Protoporphyrinogen oxidase inhibitors

A compound of formula (I):

• or suitable salt thereof, wherein:
• X is —CH or —N;
• R1 is —SR1a or —S(O)2R1b;
• R1a is C1-4alkyl optionally substituted with phenyl, C(O)OR1c, or C(O)N(R1c)2;
• each R1c is independently, H, CH2CH2OC(O)R1d, or optionally substituted C1-4alkyl, wherein the optional substituents are C3-6cycloalkyl, C(O)OC1-4alkyl, or up to 3 F atoms, or two R1c with an intervening nitrogen atom form a 5-6 membered ring optionally substituted with C(O)OH or C(O)OC1-4alkyl;
• R1d is C1-4alkyl or C1-4alkenyl;
• R1b is CH2C(O)C1-4alkyl or N(R1e)R1f;
• R1e is H, C1-4alkyl, C1-4alkenyl, C1-4alkynyl, C(O)C1-2alkyl, or OC1-4alkyl;
• R1f is H, C1-6alkyl, C(O)C(O)C1-4alkyl, C(O)R1g, or S(O)2R1g, or R1e and R1f together with the intervening nitrogen atom form a 5-6 membered ring, optionally containing up to two C(O) ring members;
• R1g is C1-4alkyl, C1-4alkenyl, phenyl, Het, N(Rh)2, OC1-4alkyl, C3-6cycloalkyl, or CH2(OCH2CH2)4CH3, wherein each alkyl group is optionally substituted with up to 3 F atoms, phenyl, C3-6cycloalkyl, OH, OC1-4alkyl, wherein each cycloalkyl group is optionally substituted with OH or OC1-4alkyl, wherein each phenyl is optionally substituted with up to 3 Cl or F atoms, and wherein Het is a 5-6 membered heterocyclic ring containing up to two ring members selected from O, N, S, or S(O)2 and optionally substituted with OH or OC1-4alkyl;
• each Rh is, independently H, C1-4alkyl, benzyl, or phenyl;
• each of R2 and R3 is Cl or F;
• and
• each of R4, R5, and R6 is F or H, wherein Ring A comprises at least 4 F atoms.