Synthetic lipid-like materials for brain delivery

A compound of formula I:

• Y—W—RLipid (I),
• or a pharmaceutically acceptable salt thereof, wherein
• Y is
• W is —NR20;
• R20 is RLipid;
• and
• each instance of RLipid is independently of the structure:
• wherein:
• each instance of R1 and R2 is independently —H, —OH, —NHR30, or —SH;
• R3 and R4 are both —H;
• or R3 and R4 are taken together to form an oxo (═O) group;
• Z is —CH2—, —O—, —NR30—, or —S—;
• X and Y1 are independently —CH2—, —NR30—, —O—, —S—, or —Se—;
• m is an integer selected from 1-3;
• n is an integer selected from 1-14;
• p is 0 or 1;
• q is an integer selected from 1-10;
• t is 0 or 1;
• and
• R30 is —H, C1-6 alkyl, C2-6 alkenyl, or C2-6 alkynyl.