[OH:1][C:2]1[CH:3]=[C:4]([CH:9]=[CH:10][C:11]=1[CH3:12])[C:5]([NH:7][NH2:8])=[O:6].NN.[C:15](OCC)(OCC)(OCC)[CH3:16]>C1(C)C(C)=CC=CC=1>[CH3:12][C:11]1[CH:10]=[CH:9][C:4]([C:5]2[O:6][C:15]([CH3:16])=[N:8][N:7]=2)=[CH:3][C:2]=1[OH:1]A suspension of ethyl 3-hydroxy-4-methylbenzoate (3.60 g, 20 mmol) (from Example 6 supra) in anhydrous hydrazine (10 mL, 318 mmol) (Aldrich) was heated at reflux (150° C. bath temperature) for 3 hours. After cooling to room temperature, mixture was concentrated under reduced pressure to give a dry solid. This was suspended in xylene (50 mL) and concentrated under reduced pressure. Resulting solid was suspended in triethyl ortho-aceate (35 mL, 191 mmol) (Aldrich) and heated at reflux (150° C. bath temperature) for 20 hours with removal of ethanol. After cooling, dichloromethane was added and solid was collected by filtration to give 2-methyl-5-(5-methyl-[1,3,4]oxadiazol-2-yl)-phenol as an off-white crystalline material. (Yield 2.28 g, 60.0%).
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