Optimised compounds

A compound of formula (VII):

• A-Y—NH—(CH2)p—O—(CH2—CH2—O)n—[(CH2)mCO—L-]qR3 (VII),
• wherein:
• A has the structure:
• Y is:
• n is 10 to 100;
• m is 1, 2, 3 or 4;
• each g is independently 10, 11, 12, 13, 14, 15, 16, 17 or 18;
• p is 2, 3 or 4;
• q is null or 1;
• R1 and R2 are independently selected from the group consisting of H, —CH2OH, —CH2CH2OH, —CH(CH3)OH, —CH2OPO(OH)2, —CH2C(═O)NH2, —CH2CH2C(═O)OH and —CH2CH2C(═O)OR8, wherein any one of the alkyl hydrogens can be replaced with a halogen;
• R6 and R7 are independently selected from the group consisting of H, a straight or branched C1-C4 alkyl, and —C(═O)CH3;
• R8 is selected from the group consisting of H and a straight or branched C1-C6 alkyl;
• R9 and R10 are independently selected from the group consisting of —NH—, —O— or a single bond;
• z is 1 or 2;
• X is S or S(═O);
• wherein when q=1, R3 is —NH2 or —OH;
• wherein when q=0, R3 is H;
• L is null or consists of 1 to 10 units, wherein each unit is a natural alpha amino acid or derived from a natural alpha amino acid, and has the formula:
• wherein R4 is H;
• and
• R5 is the side chain, or second hydrogen of the amino acid or a pharmaceutically acceptable salt or prodrug thereof.