Nuclear transport modulators and uses thereof

A compound of structural formula (Ia), (Ib), or (Ic):

• or a pharmaceutically acceptable salt thereof, wherein:
• each R1, if present, is independently selected from —CF3, halo, —OH, C1-C3 alkyl, C3-C6 cycloalkyl, 3-18-membered heterocyclyl, halo-C1-C3 alkyl, —NH2, —NO2, —NH(C1-C3 alkyl), —N(C1-C3 alkyl)(C1-C3 alkyl), —C(O)OH, —C(O)O—(C1-C6 alkyl), —C(O)—(C1-C3 alkyl), —O—(C1-C3 alkyl), —O—(C1-C3 haloalkyl), and —S—(C1-C3 alkyl);
• R2 and Rb are each independently selected from:
• —C(O)—N(R5)(R6), halogen, C(O)—O—R3, —C(O)—N(R7)—N(R5)(R6), —C(O)—N(R7)—N(R7)—C(O)—R4 and —C(O)—N(R7)—N(R7)—S(O)1-2—R4, a 6-18-membered aryl or a 5-18-membered heteroaryl;
• R3 is selected from hydrogen, C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, C3-C18 carbocyclyl, C6-C18 aryl, 3-18-member heterocyclyl and 5-18-member heteroaryl;
• R4 is selected from —N(H)(C3-C6 cycloalkyl), —N(C1-C4 alkyl)(C3-C6 cycloalkyl), —C1-C6 alkyl, —(C0-C4 alkylene)-C3-C18 carbocyclyl, —(C0-C4 alkylene)-3-18-member heterocyclyl, —(C0-C4 alkylene)-C6-C18 aryl, and —(C0-C4 alkylene)-5-18-member heteroaryl;
• R5 and R6 are each independently selected from hydrogen, C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, C3-C18 carbocyclyl, C6-C18 aryl, 3-18-member heterocyclyl and 5-18-member heteroaryl;
• or
• R5 and R6 are taken together with the nitrogen atom to which they are commonly attached to form a 3-18-member heterocyclyl or 5-18-member heteroaryl;
• and
• each R7 is independently hydrogen or C1-C4 alkyl;
• n is 0, 1, 2, 3, 4 or 5;
• wherein, unless otherwise designated, each alkyl, alkenyl, alkynyl, alkylene, carbocyclyl, aryl, cycloalkyl, heterocyclyl and heteroaryl is optionally and independently substituted.