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To a suspension of 22.0 g (0.101 mol) of 3-nitro-1-napthalene-carboxylic acid (prepared according to procedures in Duffy, K. J., et al., in J. Med. Chem. 2001, 44, 3730-3745) in 1 L of anhydrous dichloromethane at 0° C. under an atmosphere of nitrogen was added 9.8 mL (0.11 mol) of oxalyl chloride followed by 0.80 mL (10 mmol) of anhydrous N,N-dimethylformamide. The reaction mixture was allowed to gradually warm to ambient temperature for 3 h until gas evolution ceased. The resulting homogeneous solution was concentrated in vacuo to remove all volatiles. The residue was then dissolved in 1 L of anhydrous dichloromethane and 20 mL (0.51 mol) of anhydrous methanol was added. After stirring for 1 h, the reaction was carefully quenched with a saturated aqueous sodium bicarbonate solution (500 mL). The organic layer was separated and the aqueous layer was extracted with dichloromethane (2×250 mL). The combined organic layers were washed with brine (300 mL), dried over magnesium sulfate, filtered and concentrated in vacuo to yield the title compound as a pale yellow solid, which was used without further purification. LC/MS 232.2 (M+1). Step B: Methyl 3-amino-1-naphthoate. To 1.15 g (1.08 mmol) of 10% palladium on carbon was added a suspension of 11.6 g (50.0 mmol) of the above methyl 3-nitro-1-naphthoate in 150 mL of anhydrous ethanol and 40 mL of anhydrous dichloromethane. The resulting suspension was agitated under an atmosphere of hydrogen at 40 psi for 3 h during which time all solids dissolved. The reaction mixture was filtered through a plug of Celite®, which was subsequently washed with dichloromethane (300 mL). The combined filtrates were concentrated in vacuo to yield the title compound as a pale green gum which was used without further purification. LC/MS 202.1 (M+1). Step C: Methyl 3-bromo-1-naphthoate. A solution of 4.34 g (62.9 mmol) of sodium nitrite in 40 mL of water was added dropwise to a 0° C. solution of 11.5 g (57.2 mmol) of the above methyl 3-amino-1-naphthoate in 300 mL of ethanol and 60 mL of 48% aqueous hydrobromic acid while maintaining an internal reaction temperature below 10° C. After complete addition of the aqueous solution the resulting dark red reaction mixture was stirred at 0° C. for an additional 30 min. The cooled (0° C.) reaction mixture was then added over 20 min. to a suspension of 8.21 g (57.2 mmol) of cuprous bromide in 60 mL of ethanol and 60 mL of 48% aqueous hydrobromic acid heated to 95° C. After stirring for 30 min. the reaction mixture was cooled to 0° C. and carefully partitioned between ethyl ether (250 mL) and water (600 mL). The organic layer was separated and the aqueous layer was extracted with ethyl ether (2×300 mL). The combined organic layers were washed with brine (100 mL), dried over magnesium sulfate, filtered and concentrated in vacuo. The residue was passed through a plug of silica gel eluting with 30% dichloromethane in hexanes and the filtrate concentrated in vacuo. Flash chromatography on a Biotage® purification apparatus (silica gel, 7% dichloromethane/hexanes) yielded the title compound as a colorless solid. 1H NMR (DMSO-d6): δ 8.67 (d, J=8.4 Hz, 1H), 8.50 (s, 1H), 8.15 (s, 1H), 8.02 (d, J=8.0 Hz, 1H), 7.68-7.71 (m, 1H), 7.63-7.66 (t, J=7.6 Hz, 1H), 3.94 (s, 3H). LC/MS 265.0 (M+1) and 267.0 (M+3). Step D: tert-Butyl 4-[4-(methoxycarbonyl-2-naphthyl]-1-piperazinecarboxylate. To 670 mg (2.53 mmol) of the compound from Step C and 517 mg (2.78 mmol) of tert-butyl 1-piperazinecarboxylate in a dry 50 mL flask was added 20 mL anhydrous dioxane. The system was purged for 5 min., and then flushed with nitrogen. 1.23 g (3.80 mmol) of cesium carbonate was added to the flask, and the system was again purged for 5 min with nitrogen, then flushed with nitrogen. Next, 60 mg (0.1 5 mmol) of 2-dicyclohexylphosphino-2′(N,N-dimethylamino)biphenyl, and 73 mg (0.13 mmol) of bis(dibenzylideneacetone)palladium were added, and the system was purged with nitrogen one last time. The reaction mixture was heated at 85° C. under nitrogen for 24 h. After cooling to room temperature, the solution was filtered through Celite® and concentrated in vacuo to yield an orange oil, which was purified using a Biotage Horizon® system (10%-25% ethyl acetate in hexanes gradient) to give the title compound. LC/MS: 371.2 (M+1) Step E: Methyl 3-(1-piperazinyl)-1-naphthoate trifluoroacetic acid salt. To 120 mg (0.324 mmol) of the compound from Step D was added 5 mL dichloromethane and 0.5 mL trifluoroacetic acid. When the reaction was complete by LC-MS (1 h), the solution was concentrated in vacuo. The resulting oil was triturated with ethyl ether (3 mL) and filtered to give the title compound as a pale green solid. 1H NMR (CD3OD): δ 8.64 (d, J=8.2 Hz, 1H), 7.99 (d, J=2.5 Hz, 1H), 7.81 (d, J=8.0 Hz, 1H), 7.46 (m, 3H), 3.98 (s, 3H), 3.54 (t, J=4.8 Hz, 4H), 3.43 (t, J=5.5 Hz, 4H). LC/MS 271.0 (M+1).

1. customwas used without further purification
2. temperaturewhile maintaining an internal reaction temperature below 10° C
3. additionAfter complete addition of the aqueous solution
4. customthe resulting dark red reaction mixture
5. temperatureThe cooled
6. custom(0° C.) reaction mixture
7. temperatureheated to 95° C
8. stirringAfter stirring for 30 min. the reaction mixture
9. temperaturewas cooled to 0° C.
10. customcarefully partitioned between ethyl ether (250 mL) and water (600 mL)
11. customThe organic layer was separated
12. extractionthe aqueous layer was extracted with ethyl ether (2×300 mL)
13. washThe combined organic layers were washed with brine (100 mL)
14. dry with materialdried over magnesium sulfate
15. filtrationfiltered
16. concentrationconcentrated in vacuo
17. concentrationthe filtrate concentrated in vacuo
18. customFlash chromatography on a Biotage® purification apparatus (silica gel, 7% dichloromethane/hexanes)