Processes for intermediates for macrocyclic compounds
View Patent ↗The present invention is directed to novel macrocyclic compounds of formula (I) and their pharmaceutically acceptable salts, hydrates or solvates: wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , n 1 , m, p Z 1 , Z 2 , and Z 3 are as describe in the specification. The invention also relates to compounds of formula (I) which are antagonists of the motilin receptor and are useful in the treatment of disorders associated with this receptor and with or with motility dysfunction.
1. A process for preparing a compound of formula (I):
wherein R 1 is C 1 -C 4 alkyl; the process comprising:
(a) contacting a compound of formula (A):
with a compound of formula (B):
in the presence of an azodicarboxylate reagent and a phosphine reagent, or in the presence of a combined Mitsunobu reagent, to form a compound of formula (C):
wherein X is halogen or triflate and PG 2 is an ester protecting group;
(b) contacting the compound of formula (C) with a reducing agent to form a compound of formula (D):
(c) contacting the compound of formula (D) with a compound of formula (E):
in the presence of a palladium catalyst, optionally a copper salt and/or optionally an organic base to form a compound of formula (F):
wherein PG 1 is hydrogen or an amine protecting group;
(d) contacting the compound of formula (F) with hydrogen in the presence of a metal catalyst to form the compound of formula (G):
(e) removing the PG 1 protecting group, when present, from the compound of formula (G) to provide the compound of formula (I).
2. The process of claim 1 , wherein the compound of formula (I) is:
3. The process of claim 1 wherein the compound of formula (B) is selected from the group consisting of:
wherein PG 2 is an ester protecting group.
4. The process of claim 1 , wherein X is iodine.
5. The process of claim 1 , wherein PG 1 is hydrogen.
6. The process of claim 1 , wherein PG 1 is a carbamate protecting group.
7. The process of claim 1 , wherein PG 1 is selected from the group consisting of tert-butoxycarbonyl (Boc), benzyloxycarbonyl (Cbz), 9-fluorenylmethoxycarbonyl (Fmoc), α,α-dimethyl-3,5-dimethoxybenzyloxycarbonyl (Ddz) and allyloxycarbonyl (Alloc).
8. The process of claim 1 , wherein PG 2 is an alkyl group or an alkyl group substituted with an aryl group.
9. The process of claim 1 , wherein PG 2 is methyl, ethyl or benzyl.
10. The process of claim 1 , wherein the azodicarboxylate reagent is selected from the group consisting of diethylazodicarboxylate (DEAD) and diisopropylazodicarboxylate (DIAD).
11. The process of claim 1 , wherein the phosphine reagent is selected from the group consisting of triphenylphosphine and tributylphosphine.
12. The process of claim 1 , wherein the combined Mitsunobu reagent is a triphenylphosphine-diisopropylazodicarboxylate (DIAD) adduct.
13. The process of claim 1 , wherein the reducing agent is selected from the group consisting of an aluminum hydride and a borohydride.
14. The process of claim 1 , wherein the reducing agent is selected from the group consisting of diisobutylaluminum hydride (DIBAL-H), lithium aluminum hydride (LAH), and lithium borohydride.
15. The process of claim 1 , wherein the palladium catalyst is selected from the group consisting of dichlorobis(triphenylphosphine)palladium(II), dichlorobis(acetonitrile)-palladium(II), dichlorobis(benzonitrile)palladium(II), tetrakis(triphenyl-phosphine)palladium(0) and tris(dibenzylideneacetone)dipalladium(0).
16. The process of claim 1 , wherein the copper salt is a copper halide.
17. The process of claim 1 , wherein the copper salt is copper (I) iodide.
18. The process of claim 1 , wherein the copper salt is not present.
19. The process of claim 1 , wherein the organic base is selected from the group consisting of a dialkylamine, a trialkylamine and an aromatic amine.
20. The process of claim 1 , wherein the organic base is triethylamine (TEA), diisopropylamine or N,N-diisopropylethylamine (DIPEA).
21. The process of claim 1 , wherein the organic base is not present.
22. The process of claim 1 , wherein (c) is conducted in the presence of a phosphine.
23. The process of claim 1 , wherein the metal catalyst is palladium on carbon or platinum oxide.
24. The process of claim 1 , wherein compound (G) is subjected to a purification step comprising chromatography or dry pack chromatography.
25. The process of claim 1 , wherein contacting the compound of formula (A) with a compound of formula (B) in the presence of an azodicarboxylate reagent and a phosphine reagent, or in the presence of a combined Mitsunobu reagent, to form a compound of formula (C) is replaced by contacting the compound of formula (A) with a compound of formula (G):
wherein Y is a leaving group, R 1 is C 1 -C 4 alkyl and PG 7 is an ester protecting group, in the presence of a base to form the compound of formula (C).
26. The process of claim 25 , wherein Y is a halogen or a sulfonate.
27. The process of claim 25 , wherein Y is selected from the group consisting of 4-methylbenzenesulfonate (tosylate), methanesulfonate (mesylate), 2-nitrobenezenesulfonate, 4-nitrobenezenesulfonate (nosylate), 2,4-dinitrobenezenesulfonate, 4-bromobenezenesulfonate (brosylate), trifluoromethanesulfonate (triflate), chloride, bromide and iodide.
28. The process of claim 25 , wherein the base is selected from the group consisting of a hydrogen carbonate salt, a carbonate salt, a trialkylamine and an aromatic amine.