Patent ID: 7659241

Claim:
A compound of the Formula Ia: L A a -W w -Y y -D) p Ia; or a pharmaceutically acceptable salt thereof, wherein, L— is a Ligand unit; —A— is a Stretcher unit; a is 1; each —W— is independently an Amino Acid unit; —Y— is a self-immolative Spacer unit; w is an integer ranging from 2 to 12; y is 1 or 2; p ranges from 1 to about 20; and —D is a Drug unit of the formula: the wavy line indicates the point of attachment to the Spacer unit, and independently at each location: R 2 is selected from the group consisting of —H and —C 1 -C 8 alkyl; R 3 is selected from the group consisting of —H, —C 1 -C 8 alkyl, —C 3 -C 8 carbocycle, —O—(C 1 -C 8 alkyl), -aryl, —C 1 -C 8 alkyl-aryl, —C 1 -C 8 alkyl-(C 3 -C 8 carbocycle), —C 3 -C 8 heterocycle and —C 1 -C 8 alkyl-(C 3 -C 8 heterocycle); R 4 is selected from the group consisting of —H, —C 1 -C 8 alkyl, —C 3 -C 8 carbocycle, —O—(C 1 -C 8 alkyl), -aryl, —C 1 -C 8 alkyl-aryl, —C 1 -C 8 alkyl-(C 3 -C 8 carbocycle), —C 3 -C 8 heterocycle and —C 1 -C 8 alkyl-(C 3 -C 8 heterocyle); R 5 is selected from the group consisting of —H and -methyl; or R 4 and R 5 join and form a ring with the carbon atom to which they are attached and R 4 and R 5 have the formula —(CR a R b ) n — wherein: R a and R b are independently selected from the group consisting of —H, —C 1 -C 8 alkyl and —C 3 -C 8 carbocycle and n is selected from the group consisting of 2, 3, 4, 5 and 6; R 6 is selected from the group consisting of —H and —C 1 -C 8 alkyl; R 7 is selected from the group consisting of —H, —C 1 -C 8 alkyl, —C 3 -C 8 carbocycle, —O—(C 1 -C 8 alkyl), -aryl, —C 1 -C 8 alkyl-aryl, —C 1 -C 8 alkyl-(C 3 -C 8 carbocycle), —C 3 -C 8 heterocycle and —C 1 -C 8 alkyl-(C 3 -C 8 heterocycle); each R 8 is independently selected from the group consisting of —H, OH, C 1 -C 8 alkyl, —C 3 -C 8 carbocycle and —O—(C 1 -C 8 alkyl); R 9 is selected from the group consisting of —H and —C 1 -C 8 alkyl; R 10 is selected from the group consisting of: Z is —O—, —S—, —NH— or —N(R 14 )—; R 11 is selected from the group consisting of —H, —OH, —NH 2 , NHR 14 , —N(R 14 ) 2 , —C 1 -C 8 alkyl, —C 3 -C 8 carbocycle, —O—(C 1 -C 8 alkyl), -aryl, —C 1 -C 8 alkyl-aryl, —C 1 -C 8 alkyl-(C 3 -C 8 carbocycle), —C 3 -C 8 heterocycle and —C 1 -C 8 alkyl-(C 3 -C 8 heterocycle); or R 11 is an oxygen atom which forms a carbonyl unit (C═O) with the carbon atom to which it is attached and a hydrogen atom on this carbon atom is replaced by one of the bonds in the (C═O) double bond; each R 12 is independently selected from the group consisting of -aryl and C 3 -C 8 heterocycle; R 13 is selected from the group consisting —H, —OH, —NH 2 , —NHR 14 , —N(R 14 ) 2 , —C 1 -C 8 alkyl, —C 3 -C 8 carbocycle, —O—(C 1 -C 8 alkyl), -aryl, —C 1 -C 8 alkyl-aryl, —C 1 -C 8 alkyl-(C 3 -C 8 carbocycle), C 3 -C 8 heterocycle and —C 1-8 alkyl-(C 3 -C 8 heterocycle); and each R 14 is independently —H or —C 1 -C 8 alkyl.