Peptide for cytosolic delivery

A peptide represented by the following formula (IA):

• R1-(IWLTALX5FLGX6X1AAX7X2X3AX8QX4LSX9L-Y)n-R2 (IA)
• wherein X1 and X2 are the same or different, and each represents H or A;
• X3 represents E, L-2-aminoadipic acid (Aad), 2-aminopimelic acid, or 2-aminosuberic acid;
• X4 represents Q, L-2-aminoadipic acid (Aad), 2-aminopimelic acid, 2-aminosuberic acid, or E;
• X5 to X9 are the same or different, and each represents Lys (K), Arg (R), homoarginine, ornithine, homolysine, or 2-amino-7-guanidinoheptanoic acid;
• provided that a case where X1=H, X2=H, X3=E, X4=Q, and X5 to X9=K is excluded, and
• when X4=E, and X5 to X9=K, one or both of X1 and X2 are A;
• R1 represents a hydrogen atom, an alkyl group, an acyl group, an alkoxycarbonyl group, an aralkyloxycarbonyl group, an aryloxycarbonyl group, an alkoxy group, an aralkyloxy group, an aryloxy group, or a target substance;
• R2 represents a hydroxyl group (OH), an amino group (NH2), a monoalkylamino group, a monoarylamino group, monocycloalkylamino, a dialkylamino group, an alkoxy group, an aralkyloxy group, an aryloxy group, or a target substance;
• Y represents a single bond or a spacer;
• and
• n is 2, 3, 4, 5, 6, 7, 8, 9 or 10.

A dendrimer represented by the following formula (IB):

• Z—(Ra)m (IB)
• wherein Z represents a branched multivalent linker;
• Ra is the same or different, and each represents R1-IWLTALX5FLGX6X1AAX7X2X3AX8QX4LSX9L-Y- or Y-IWLTALX5FLGX6X1AAX7X2X3AX*QX4LSX9L-R2;
• wherein X1 and X2 are the same or different, and each represents H or A;
• X3 represents E, L-2-aminoadipic acid (Aad), 2-aminopimelic acid, or 2-aminosuberic acid;
• X4 represents Q, L-2-aminoadipic acid (Aad), 2-aminopimelic acid, 2-aminosuberic acid, or E;
• X5 to X9 are the same or different, and each represents Lys (K), Arg (R), homoarginine, ornithine, homolysine, or 2-amino-7-guanidinoheptanoic acid;
• provided that a case where X1=H, X2=H, X3=E, X4=Q, and X5 to X9=K is excluded, and
• when X4=E, and X5 to X9=K, one or both of X1 and X2 are A;
• R1 represents a hydrogen atom, an alkyl group, an acyl group, an alkoxycarbonyl group, an aralkyloxycarbonyl group, an aryloxycarbonyl group, an alkoxy group, an aralkyloxy group, an aryloxy group, or a target substance;
• R2 represents a hydroxyl group (OH), an amino group (NH2), a monoalkylamino group, a monoarylamino group, monocycloalkylamino, a dialkylamino group, an alkoxy group, an aralkyloxy group, an aryloxy group, or a target substance;
• Y represents a single bond or a spacer;
• and
• m is an integer of 2 to 8.