C17-heteroaryl derivatives of oleanolic acid and methods of use thereof
Disclosed herein are novel C17-heteroaryl derivatives of oleanolic acid, including those of the formula: wherein the variables are defined herein. Also provided are pharmaceutical compositions, kits and articles of manufacture comprising such compounds. Methods and intermediates useful for making the compounds, and methods of using the compounds, for example, as antioxidant inflammation modulators, and compositions thereof are also provided.
1. A method of synthesizing a compound of formula I:
or a pharmaceutically acceptable salt thereof, wherein:
n is 0-3;
Ar is heteroarenediyl (C≤8) or substituted heteroarenediyl (C≤8) ; and
Y is:
hydrogen, hydroxy, halo, amino, cyano, or —NCO; or
alkyl (C≤8) , alkenyl (C≤8) , alkynyl (C≤8) , aryl (C≤12) , aralkyl (C≤12) , heteroaryl (C≤8) , heterocycloalkyl (C≤12) , acyl (C≤12) , alkoxy (C≤8) , aryloxy (C≤12) , acyloxy (C≤8) , alkylamino (C≤8) , dialkylamino (C≤8) , arylamino (C≤8) , aralkylamino (C≤8) , alkylthio (C≤8) , acylthio (C≤8) , alkylsulfonylamino (C≤8) , or a substituted version of any of these groups;
the method comprising:
(a) obtaining a compound of formula Ia:
or a salt thereof, wherein:
n is 0-3;
X 1 is —O— or —NH—;
X 2 is ═O or ═NH; and
Y is:
hydrogen, hydroxy, halo, amino, cyano, or —NCO; or
alkyl (C≤8) , alkenyl (C≤8) , alkynyl (C≤8) , aryl (C≤12) , aralkyl (C≤12) , heteroaryl (C≤8) , heterocycloalkyl (C≤12) , acyl (C≤12) , alkoxy (C≤8) , aryloxy (C≤12) , acyloxy (C≤8) , alkylamino (C≤8) , dialkylamino (C≤8) , arylamino (C≤8) , aralkylamino (C≤8) , alkylthio (C≤8) , acylthio (C≤8) , alkylsulfonylamino (C≤8) , or a substituted version of any of these groups; and
(b) heating the compound of formula Ia in an organic solvent to form the compound of formula I.
2. The method of claim 1 , wherein the compound of formula Ia in the solvent is heated to reflux.
3. The method of claim 1 , wherein heating comprises applying microwave radiation to the compound of formula Ia in the organic solvent.
4. The method of claim 1 , wherein the organic solvent is a hydrocarbon solvent.
5. The method of claim 4 , wherein the hydrocarbon solvent is an aromatic hydrocarbon solvent.
6. The method of claim 5 , wherein the aromatic hydrocarbon solvent is toluene.
7. The method of claim 1 , wherein n is 0.
8. The method of claim 1 , wherein n is 1.
9. The method of claim 1 , wherein X 1 is —NH— and X 2 is ═O.
10. The method of claim 1 , wherein X 1 is —O— and X 2 is ═NH.
11. The method of claim 1 , wherein Y is —H.
12. The method of claim 1 , wherein Y is alkyl (C≤4) .
13. The method of claim 12 , wherein Y is methyl, n-propyl, isopropyl, or cyclopropyl.
14. The method of claim 1 , wherein Y is substituted alkyl (C≤4) .
15. The method of claim 14 , wherein Y is methoxymethyl.
16. The method of claim 1 , wherein the compound of formula Ia is further defined as:
or a salt thereof.
17. The method of claim 1 , wherein the compound of formula I is further defined as:
or a salt thereof.
18. The method of claim 1 , wherein the compound in the organic solvent is heated to at least about 100° C.
19. The method of either claim 1 or claim 18 , wherein the compound in the organic solvent is heated to about 110° C.