C([O:3][C:4](=O)[CH2:5][CH2:6][C:7]1[C:8]([CH3:14])=[N:9][N:10]([CH3:13])[C:11]=1[CH3:12])C.[H-].C([Al+]CC(C)C)C(C)C>O1CCCC1.C1(C)C=CC=CC=1>[CH3:13][N:10]1[C:11]([CH3:12])=[C:7]([CH2:6][CH2:5][CH:4]=[O:3])[C:8]([CH3:14])=[N:9]1Dissolve 3-(1,3,5-trimethyl-1H-pyrazol-4-yl)-propionic acid ethyl ester (1.94 g, 9.23 mmol) in tetrahydrofuran (78 mL). Cool to −78° C. in a dry ice/acetone bath and treat dropwise with 1 M diisobutylaluminum hydride in toluene (10.15 mL). Stir reaction mixture at −78° C. for one hr. and add 1 M diisobutylaluminum hydride in toluene (10.15 mL). Stir reaction mixture at −78° C. for one hr. and add 1 M diisobutylaluminum hydride in toluene (10.15 mL). Stir reaction mixture at −78° C. for 1 hr. and add 1 M diisobutylaluminum hydride in toluene (10.15 mL). Stir reaction mixture at −78° C. for 1 hr. and quench with aqueous saturated potassium sodium tartrate tetrahydrate solution. Add ethyl acetate (150 mL), and stir for 3 hr. at room temperature. Separate organic layer, extract aqueous layer 3 times with ethyl acetate, dry (magnesium sulfate), filter, concentrate and purify (silica gel chromatography, eluting with 1:1 to 100% ethyl acetate:hexanes), to give the title preparation (760 mg, 51%). GC-MS m/z=166 [M+].
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