Oligosaccharide compounds and complexes

A compound of formula I:

• or a pharmaceutically acceptable salt thereof, wherein:
• A is A1, A2, or A3:
• each of R1 and R2 are independently selected, at each instance, from H, Ra, and —C(O)—Ra, wherein at least one instance of R1 or R2 is not H;
• each Ra is independently selected from C1-C20 aliphatic, C3-C20 cycloaliphatic, C5-C6 aryl, 3- to 12-membered heterocyclyl comprising 1 to 3 heteroatoms selected from N, O, and S, wherein each Ra is optionally substituted with one or more Rb;
• each Rb is independently selected from halogen, —N3, —Rc, —ORc, —SRc, —NHRc, —C(O)—Rc, —OC(O)Rc, —NHC(O)Rc, —C(O)NHRc, and —NHC(O)NHRc;
• each Rc is independently selected from optionally substituted C1-C20 aliphatic, optionally substituted C3-C20 cycloaliphatic, optionally substituted C5-C6 aryl, optionally substituted 3- to 12-membered heterocyclyl comprising 1 to 3 heteroatoms selected from N, O, and S, and optionally substituted 4- to 12-membered heteroaryl comprising 1 to 3 heteroatoms selected from N, O, and S;
• X1 and X2 are each independently selected from —S—, and —NH—;
• Y1 and Y2 are each independently an optionally substituted C1-30 aliphatic group wherein one or more carbons are optionally and independently replaced by -Cy-, —NH—, —NHC(O)—, —C(O)NH—, —NHC(O)O—, —OC(O)NH—, —NHC(O)NH—, —NHC(S)NH—, —C(S)NH—, —C(O)NHSO2—, —SO2NHC(O)—, —OC(O)O—, —O—, —C(O)—, —OC(O)—, —C(O)O—, —SO—, or —SO2—;
• each Cy is independently an optionally substituted C3-C14 cycloaliphatic, 5- to 14-membered heterocyclyl ring having 1-3 heteroatoms selected from N, O, and S, and optionally substituted 5- to 14-membered heteroaryl ring having 1-3 heteroatoms selected from N, O, and S;
• Z1 and Z2 are each independently a cationic or ionizable group selected from optionally substituted 5- to 14-membered heterocyclyl ring having 1-3 heteroatoms selected from N, O, and S, optionally substituted 5- to 14-membered heteroaryl ring having 1-3 heteroatoms selected from N, O, and S, —N+(M)3,
• each M is independently —C0-C6 aliphatic-Rz or —C0-C6 aliphatic-N+(Rz)3;
• each Rz is independently selected from H, optionally substituted C1-C6 aliphatic, optionally substituted C3-C20 cycloaliphatic, optionally substituted C5-C6 aryl, optionally substituted 3- to 12-membered heterocyclyl comprising 1 to 3 heteroatoms selected from N, O, and S, and optionally substituted 4- to 12-membered heteroaryl comprising 1 to 3 heteroatoms selected from N, O, and S;
• or
• two or more Rz can come together with the atoms to which they are attached to form an optionally substituted 3- to 12-membered heterocyclyl comprising 1 to 3 heteroatoms selected from N, O, and S, or an optionally substituted 4- to 12-membered heteroaryl comprising 1 to 3 heteroatoms selected from N, O, and S;
• and
• p is an integer selected from 1, 2, 3, 4, or 5;
• provided that when A is A1, then:
• (i) each R1 and R2 is not —CO—(CH2)4—CH3, X1 and X2 are not both —S—, Y1 and Y2 are not both —(CH2)2— and Z1 and Z2 are not both —N+(H)3,
• (ii) each R1 and R2 is not —(CH2)5—CH3 or —(CH2)13—CH3, X1 and X2 are not both —S—, Y1 and Y2 are not both —(CH2)2—, and Z1 and Z2 are not both —N+(H)3,
• (iii) each R1 and R2 is not —CO—(CH2)4—CH3, X1 and X2 are not both —S—, Y1 and Y2 are not both —(CH2)2—NH—C(S)—NH—(CH2)2—, and Z1 and Z2 are not both —N+(H)3, and
• (iv) Cy is not triazolyl.