Compounds for the treatment of paramyxovirus viral infections

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

• Ab-Lb-Yb (II)
• wherein:
• Lb is selected from the group consisting of:
• Ab is an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted aryl, an optionally substituted aryl(C1-2 alkyl), an optionally substituted heteroaryl or an optionally substituted heterocyclyl;
• Yb is an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted aryl, an optionally substituted heteroaryl or an optionally substituted heterocyclyl;
• when Lb is Formula (IIc), between X2b and X3b represents a single or double bond between X2b and X3b, when between X2b and X3b is a double bond, then X1b is independently NR3b or CR3b1R3b2, X2b is N (nitrogen) or CR7b1, and X3b is N (nitrogen) or CR4b;
• when between X2b and X3b is a single bond, then X1b is independently NR3b or CR3b1R3b2, X2b is O (oxygen), NR7b or C(R7b2)(R7b3), and X3b is NR4b, C(═O) or CR4bR8b;
• or
• X1b, X2b and X3b are each independently C (carbon), N (nitrogen), O (oxygen) or C(═O), and form a ring or ring system selected from the group consisting of an optionally substituted aryl, an optionally substituted heteroaryl and an optionally substituted heterocyclyl by joining X1b and X3b together;
• with the proviso that the valencies of X1b, X2b and X3b are satisfied with a substituent selected from the group consisting of hydrogen and an optionally substituted C1-4 alkyl, and X1b, X2b and X3b are uncharged;
• X4b is NR6b1 or C(R6b2)2;
• X5b is NR6b3 or C(R6b4)2;
• X6b is NR6b5 or C(═O);
• X7b is NR6b6CH2 or —C(═O)— an optionally substituted pyridinyl-;
• Zb is N or CH;
• R1b is hydrogen or an unsubstituted C1-4 alkyl;
• R1b2 is hydrogen or an unsubstituted C1-4 alkyl;
• when Lb is Formula (IIg), then Yb is absent;
• when of Formula (IIl) is a single bond, then R1b3 is hydroxy;
• when of Formula (IIl) is a double bond, then R1b3 is O (oxygen);
• R2b and R2b1 are each independently hydrogen or an optionally substituted C1-4 alkyl, and when more than one R2b and/or more than one R2b1 are present, each R2b and each R2b1 is the same or different;
• R3b, R3b1 and R3b2 are each independently hydrogen or an unsubstituted C1-4 alkyl;
• R4b is hydrogen, an optionally substituted C1-4 alkyl or an optionally substituted alkoxyalkyl;
• R5b and R5b1 are each independently hydrogen or hydroxy;
• R6b1, each R6b2, R6b3, each R6b4, R6b5 and R6b6 are each independently hydrogen or an unsubstituted C1-4 alkyl;
• R7b and R7b1 are each independently be hydrogen or an unsubstituted C1-4 alkyl;
• R7b2 and R7b3 are each independently hydrogen or an unsubstituted C1-4 alkyl;
• or R7b2 and R7b3 together form ═O;
• R8b is hydrogen or an unsubstituted C1-4 alkyl;
• R9b and R10b are each independently an unsubstituted C1-4 alkyl, an unsubstituted C1-4 alkenyl or an unsubstituted C1-4 alkoxy;
• or
• R9b and R10b are taken together to form an unsubstituted aryl, an unsubstituted heteroaryl or an optionally substituted heterocyclyl;
• ring B is an optionally substituted
• or an optionally substituted
• ring B1 is an optionally substituted mono-cyclic cycloalkyl, an optionally substituted phenyl, an optionally substituted mono-cyclic heteroaryl or an optionally substituted mono-cyclic heterocyclyl;
• ring B2 is an optionally substituted heteroaryl;
• ring B3 is an optionally substituted pyridinyl;
• ring B4 is an optionally substituted heteroaryl or an optionally substituted heterocyclyl;
• ring B5 is an optionally substituted pyridinyl;
• ring B6 is an optionally substituted pyridinyl;
• ring B7 is an optionally substituted heterocyclyl;
• m1b and m2b are each independently 0 or 1;
• provided that at least one of m1b and m2b is 1;
• m3b is 0 or 1;
• and
• nb is 2 or 3.