Classes of compounds that interact with GPCRs

1. A method of identifying a candidate therapeutic agent comprising:

i) contacting a membrane comprising a G-Protein Coupled Receptor (GPCR) with a compound of general formula 1, or a pharmaceutically acceptable salt thereof

wherein the ring may be of any configuration;

Z is selected from the group consisting of: sulphur, oxygen, and NR A wherein R A is selected from the set defined for R 1 to R 5 or C1 to C15 acyl, C4 to C15 arylacyl or C4 to C15 heteroarylacyl, with the proviso that both R 1 and R A are not hydrogen,

X is selected from the group consisting of: oxygen and NR A providing that: i) X of XR 2 is NR A , ii) X of XR 3 is oxygen and R 3 is not hydrogen, iii) X of R 4 is oxygen or NR A , and X of XR 5 is oxygen, wherein at least one of OR 4 and OR 5 is OH,

R 1 to R 5 are independently selected from the group consisting of: H, C1 to C12 alkyl, C1 to C12 alkenyl, C1 to C12 alkynyl, C1 to C12 heteroalkyl, C4 to C15 aryl, C4 to C15 heteroaryl, C4 to C15 arylalkyl and C4 to C15 heteroarylalkyl substituent,

wherein, when X is NR A , both R A and the corresponding R 2 or R 4 is not hydrogen, and

ii) determining whether said compound inhibits or effects signal transduction activity of said GPCR,

wherein a compound that inhibits or effects said activity of said GPCR is a candidate therapeutic agent.

2. The method of claim 1 , wherein any one of R A or R 1 to R 5 is substituted with a moiety selected from the group consisting of: —OH, —NO, —NO 2 , —NH 2 , —N 3 , —F, —Cl, —Br, —I, —CF 3 , —CHF 2 , —CH 2 F, —C≡N, —OR, —C(═NH)NH 2 , —NH—C(═NH)—NH 2 , —COOH, —COOR, —C(═O)NHR, —NHR, —NRR, —NRRR, —NR(C═O)R, ═O, —SO 3 H, —OSO 2 NH 2 , —OPO 3 H, —OPO 2 NH 2 , —NH—NH 2 , —NH—OR, —NH—OH, —SR; wherein the group R is selected from the group consisting of: H, acyl, alkyl, alkenyl, alkynyl, heteroalkyl, aryl, heteroaryl, arylalkyl, heteroarylalkyl such that the total number of carbon atoms in each of R A , R 1 , R, R 3 , R 4 and R 5 does not exceed C1 to C15 acyl, C1 to C12 alkyl, C1 to C12 alkenyl, C1 to C12 alkynyl, C1 to C12 heteroalkyl, C4 to C15 aryl, C4 to C15 heteroaryl, C4 to C15 arylalkyl or C4 to C15 heteroarylalkyl substituent.

3. The method of claim 1 , wherein the compound is

4. The method of claim 1 , wherein the compound is

wherein A is selected from the group consisting of: N(R A )R 1 , SR 1 , or OR 1 .

5. The method of claim 1 , wherein the compound is

6. The method of claim 1 , wherein the compound is

7. The method of claim 1 , wherein the compound is

8. The method of claim 1 , wherein the compound is

9. The method of claim 1 , wherein the compound is

10. The method of claim 1 , wherein the compound is

11. The method of claim 1 , wherein the compound is

12. The method of claim 1 , wherein the compound is

13. The method of claim 1 , wherein the compound is

14. The method of claim 1 , wherein the receptor is a somatostatin receptor.

15. The method of claim 1 , wherein the receptor is a melanocortin receptor.

16. The method of claim 1 , wherein said membrane is in vitro.

17. The method of claim 1 wherein said membrane is ex vivo.

18. A method of identifying a candidate anti-inflammatory agent comprising:

i) contacting a membrane comprising a G-Protein Coupled Receptor (GPCR) with a compound of general formula 1, or a pharmaceutically acceptable salt thereof

wherein the ring may be of any configuration;

Z is selected from the group consisting of: sulphur, oxygen, and NR A wherein R A is selected from the set defined for R 1 to R 5 or C1 to C15 acyl, C4 to C15 arylacyl or C4 to C15 heteroarylacyl, with the proviso that both R 1 and R A are not hydrogen,

X is selected from the group consisting of: oxygen and NR A providing that: i) X of XR 2 is NR A , ii) X of XR 3 is oxygen and R 3 is not hydrogen, iii) X of R 4 is oxygen or NR A , and X of XR 5 is oxygen, wherein at least one of OR 4 and OR 5 is OH,

R 1 to R 5 are independently selected from the group consisting of: H, C1 to C12 alkyl, C1 to C12 alkenyl, C1 to C12 alkynyl, C1 to C12 heteroalkyl, C4 to C15 aryl, C4 to C15 heteroaryl, C4 to C15 arylalkyl and C4 to C15 heteroarylalkyl substituent,

wherein, when X is NR A , both R A and the corresponding R 2 or R 4 is not hydrogen, and

ii) determining whether said compound inhibits or effects signal transduction activity of said GPCR,

wherein a compound that inhibits or effects said activity of said GPCR is a candidate anti-inflammatory agent.

19. A method of identifying a candidate therapeutic agent for treating pain, cancer, metabolic or gastrointestinal disorders, cardiovascular disorders, central nervous system disorders, obesity or erectile dysfunction comprising:

i) contacting a membrane comprising a G-Protein Coupled Receptor (GPCR) with a compound of general formula 1, or a pharmaceutically acceptable salt thereof

wherein the ring may be of any configuration;

Z is selected from the group consisting of: sulphur, oxygen, and NR A wherein R A is selected from the set defined for R 1 to R 5 or C1 to C15 acyl, C4 to C15 arylacyl or C4 to C15 heteroarylacyl, with the proviso that both R 1 and R A are not hydrogen,

X is selected from the group consisting of: oxygen and NR A providing that: i) X of XR 2 is NR A , ii) X of XR 3 is oxygen and R 3 is not hydrogen, iii) X of R 4 is oxygen or NR A , and X of XR 5 is oxygen, wherein at least one of OR 4 and OR 5 is OH,

R 1 to R 5 are independently selected from the group consisting of: H, C1 to C12 alkyl, C1 to C12 alkenyl, C1 to C12 alkynyl, C1 to C12 heteroalkyl, C4 to C15 aryl, C4 to C15 heteroaryl, C4 to C15 arylalkyl and C4 to C15 heteroarylalkyl substituent,

wherein, when X is NR A , both R A and the corresponding R 2 or R 4 is not hydrogen, and

ii) determining whether said compound inhibits or effects signal transduction activity of said GPCR,

wherein a compound that inhibits or effects said activity of said GPCR is a candidate therapeutic agent for treating pain, cancer, metabolic or gastrointestinal disorders, cardiovascular disorders, central nervous system disorders, obesity or erectile dysfunction.