[N+:1]([C:4]1[CH:5]=[N:6][CH:7]=[CH:8][C:9]=1[O:10][CH:11]1[CH2:16][CH2:15][CH:14]([C:17]([O:19]C)=[O:18])[CH2:13][CH2:12]1)([O-:3])=[O:2].O.NC1C(C(ON2C3C=CC=CC=3N=N2)=O)=C2N=CC(CC#N)=CN2N=1.Cl>C1COCC1.C(OCC)(=O)C.CO>[N+:1]([C:4]1[CH:5]=[N:6][CH:7]=[CH:8][C:9]=1[O:10][CH:11]1[CH2:12][CH2:13][CH:14]([C:17]([OH:19])=[O:18])[CH2:15][CH2:16]1)([O-:3])=[O:2]Methyl 4-[(3-nitro-4-pyridyl)oxy]cyclohexanecarboxylate (250.0 mg, 0.8920 mmol) (prepared according to methods similar to the one depicted in Step 1 of preparation O-1) in THF (2.748 mL), Water (2.748 mL) and MeOH (1.5 mL) solution was stirred at RT and treated with Lithium hydroxide monohydrate (Water (1)) (224.6 mg, 5.352 mmol). The mixture was stirred at RT overnight, then was concentrated under reduced pressure to remove the organics. The aqueous solution was cooled in an ice bath then acidified with HCl (5.352 mL of 1 M, 5.352 mmol) to pH 4-5. Ethyl acetate was then added and the layers separated. Aqueous layer was extracted further with ethyl acetate (2×5 mL) and the combined organic layers were dried over MgSO4 and concentrated in vacuo to leave the 4-[(3-nitro-4-pyridyl)oxy]cyclohexanecarboxylic acid as a yellow oil. Used in the next step without further purification. MS (ES+) 267.0.
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