Biphenyl compounds useful as muscarinic receptor antagonists
This invention provides compounds of formula I: wherein a, b, c, d, m, n, p, s, t, W, Ar 1 , R 1 , R 2 , R 3 , R 4 , R 6 , R 7 , and R 8 are as defined in the specification. The compounds of formula I are muscarinic receptor antagonists. The invention also provides pharmaceutical compositions containing such compounds, processes and intermediates for preparing such compounds and methods of using such compounds to treat pulmonary disorders.
1. A process for preparing biphenyl-2-ylcarbamic acid 1-(2-{[4-(4-carbamoylpiperidin-1-ylmethyl)benzoyl]methylamino}ethyl)piperidin-4-yl ester, the process comprising:
reacting a compound of formula IX:
with a compound of formula VII:
in the presence of a reducing agent;
wherein a, b and c each represent 0; W represents O; m is 0; R 4 is methyl; s is 0; t is 1; Ar 1 represents phen-1,4-ylene; d is 0; n is 2; p is 0; the —CONR 7 R 8 group is in the para position; R 7 is hydrogen; and R 8 is hydrogen.
2. The process of claim 1 , where the reducing agent is hydrogen in the presence of a Group VIII metal catalyst.
3. The process of claim 1 , where the reducing agent is a metal hydride reducing agent.
4. The process of claim 3 , where the metal hydride reducing agent is sodium triacetoxyborohydride.
5. The process of claim 1 , where the reducing agent is used in combination with a titanium tetraalkoxide.
6. The process of claim 1 , where the reaction is conducted in a solvent selected from alcohols and halogenated hydrocarbons.
7. The process of claim 1 , where the reaction is performed at a temperature in the range of from 0° C. to 100° C.
8. The process of claim 7 , where the reaction is performed at a temperature in the range of from 0° C. to 10° C.
9. The process of claim 1 , where the compound of formula IX is prepared by reacting a compound of formula IV:
with a compound of formula XVII:
in the presence of a carboxylic acid/amine coupling agent.
10. The process of claim 9 , where the carboxylic acid/amine coupling agent is 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and 1-hydroxybenzotriazole hydrate.