Certain chemical entities, compositions, and methods

A compound, or pharmaceutically acceptable salt or solvate thereof, having the structure of Formula (I):

• wherein,
• X is optionally substituted alkyl, optionally substituted carbocyclyl, optionally substituted carbocyclylalkyl, optionally substituted aryl, optionally substituted aralkyl, optionally substituted heteroaryl, optionally substituted heteroaralkyl, optionally substituted heterocyclyl, or optionally substituted heterocyclylalkyl;
• L is a bond, or optionally substituted carbocyclyl, optionally substituted carbocyclylalkyl, optionally substituted heterocyclyl, or optionally substituted heterocyclylalkyl;
• R2 is optionally substituted carbocyclyl, optionally substituted aryl, optionally substituted heteroaryl, or optionally substituted heterocyclyl;
• wherein the optional substitution of the optionally substituted carbocyclyl, optionally substituted aryl, optionally substituted heteroaryl, or optionally substituted heterocyclyl is selected from the group consisting of cyano, halo, hydroxy, azido, amino, nitro, —CO2H, —S(O)—R10, —S—R10, —S(O)2—R10, optionally substituted C1-C6 alkoxy, optionally substituted aryloxy, optionally substituted heteroaryloxy, optionally substituted (heterocyclyl)-O—, optionally substituted C1-C6 alkyl, optionally substituted C2-C6 alkynyl, optionally substituted carbocyclyl, optionally substituted C2-C6 alkenyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted heterocyclyl, —N(R11)2, —CO—R10, —CO2—R10, —CON(R11)2, —NR11CO—R10, —NR11CO2—R10, —SO2N(R11)2, —C(═NR12)—N(R11)2, —NR11CO—N(R10)2, or —NR11SO2—N(R10)2;
• X3 is N or C—R3;
• X4 is N or C—R4;
• X5 is N or C—R5;
• X6 is N or C—R6;
• X8 is N or C—R8;
• R3, R4, R5, R6, and R8 are independently selected from the group consisting of hydrogen, cyano, halo, hydroxy, azido, amino, nitro, —CO2H, —S(O)—R10, —S—R10, —S(O)2—R10, optionally substituted C1-C6 alkoxy, optionally substituted C1-C6 alkyl, optionally substituted C2-C6 alkynyl, optionally substituted carbocyclyl, optionally substituted C2-C6 alkenyl, optionally substituted heterocyclyl, —N(R11)2, —CO—R10, —CO2—R10, —CON(R11)2, —NR11CO—R10, —NR11CO2—R10, —SO2N(R11)2, —C(═NR12)—N(R11)2, —NR11CO—N(R10)2, and —NR11SO2—N(R10)2;
• each R10 is independently selected from the group consisting of optionally substituted C1-C6 alkyl, optionally substituted C3-C8 carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, and optionally substituted heteroaryl;
• each R11 is independently selected from the group consisting of hydrogen, optionally substituted C1-C6 alkyl, optionally substituted C3-C8 carbocyclyl, optionally substituted heterocyclyl, optionally substituted aryl, and optionally substituted heteroaryl;
• R12 is H or optionally substituted C1-C6 alkyl;
• R9 is selected from hydrogen, optionally substituted C1-C6 alkyl, optionally substituted C3-C8 carbocyclyl, or optionally substituted C4-C10 carbocyclylalkyl;
• wherein either R9 and L, or R9 and X, may be joined together with any intervening atoms to form an optionally substituted heterocyclyl ring.