US 7,456,184 B2
Melanocortin receptor-specific compounds
Shubh D. Sharma, Cranbury, N.J. (US); Yi-Qun Shi, East Brunswick, N.J. (US); Zhijun Wu, Plainsboro, N.J. (US); Ramesh Rajpurohit, Hillsboro, N.J. (US); Annette M. Shadiack, Somerset, N.J. (US); Papireddy Purma, Plainsboro, N.J. (US); and Kevin D. Burris, Washington Crossing, Pa. (US)
Assigned to Palatin Technologies Inc., Cranbury, N.J. (US)
Filed on Apr. 30, 2004, as Appl. No. 10/837,519.
Claims priority of provisional application 60/546393, filed on Feb. 19, 2004.
Claims priority of provisional application 60/467442, filed on May 01, 2003.
Prior Publication US 2004/0224957 A1, Nov. 11, 2004
Int. Cl. A61K 31/497 (2006.01); C07D 403/02 (2006.01)
U.S. Cl. 514—254.09  [544/373] 15 Claims
 
1. A compound having the formula of structure I:

OG Complex Work Unit Drawing
or an enantiomer, stereoisomer or diastereoisomer thereof, or a pharmaceutically acceptable salt thereof,
wherein
X is CH2;
R1 is -L1-J;
one of R2a and R2b is -L2-W and the remaining of R2a and R2b is hydrogen;
R3 is -L3-Q;
L1 is a linker unit selected from the group consisting of —(CH2)2—, —(CH2)3—, —(CH2)y—C(═O)—, —C(═O)—(CH2)y— and —C(═O)—;
J is a substituted or unsubstituted ring structure selected from the group consisting of

OG Complex Work Unit Drawing
wherein, when substituted, J is substituted with one or more ring substituents independently selected from the group consisting of hydroxyl, halogen, sulfonamide, alkyl or aryl groups attached directly or through an ether linkage;
L2 is —(CH2)y—;
W is —NH—C(═NH)—NH2;
L3 is a linker unit selected from the group consisting of —(CH2)y—CH(NR6aR6b)—(CH2)y—, —(CH2)y—C(═O)—CH(NR6aR6b)—(CH2)y—, —(CH2)y—C(═O)—, —(CH2)y—CH(CH3)—C(═O)—, —C(═O)—(CH2)y—C(═O)—, —C(═O)—CH(NR6aR6b)—(CH2)y—, —C(═O)—(CH2)y—, —C(═O)—(CH2)y—CH(NR6aR6b)—, —C(═O)—(CH2)y—CH(NR6aR6b)—(CH2)y—, —C(═O)—(CH2)y—CH(NHR6aR6b)—C(═O)— and —C(═O)—;
R6a and R6b are each hydrogen;
Q is

OG Complex Work Unit Drawing
wherein R9a and R9b are ring substituents, wherein one or both are present and are the same or different and are independently hydroxyl, halogen, alkyl, or aryl groups attached directly or through an ether linkage;
R5a is a C1 to C6 aliphatic linear or branched chain;
R5b is hydrogen; and
each of R4a and R4b is hydrogen; and
y is at each occurrence independently from 1 to 6, provided that where any linker unit includes two y index values, the total of such y index values is from 2 to 6.