合成路线1

Activation of 6-hydroxy-1-naphthoic acid (I) using CDI, followed by coupling with methylamine hydrochloride (III) in DMF at 90 °C gives amide (V). Condensation of compound (V) with the aryl chloride (VI) using DMAP in 2,6-lutidine or i-PrOH at 130 °C or by means of Cs2CO3, CuI and picolinic acid or acetylacetone (Ullmann reaction) in DMF at 120 °C affords the diaryl ether (VIII), whose benzyl group is finally cleaved using TFA at 90 °C .
Esterification naphthoic acid (I) with EtOH and H2SO4 at reflux yields ethyl 6-hydroxy-1-naphthoic acid (XLIII), which then couples with aryl chloride (VI) in the presence of DMAP in 2,6-lutidine or i-PrOH at 130°C or by means of Cs2CO3, CuI and picolinic acid or acetylacetone in DMF at 120 °C (Ullmann reaction) to give diayl ether (XLIV). Finally, this compound is debenzylated with TFA at 90 °C .