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3,5-Dimethoxy-benzoic acid methyl ester (4.0 g) was dissolved in MeCN (28 mL), and NBS (4.4 g) was added at 0° C. After stirring at room temperature for 3 hours, saturated Na2SO3 (15 mL) was added. The mixture was evaporated under vacuum and extracted with ether (1×, 500 mL). After the solvent was removed, the crude material was subjected to silica gel chromatography using effluent of 10-40% ethyl acetate and hexanes. The fractions containing product were combined and the solvent was removed under reduced pressure to provide 2-bromo-3,5-dimethoxy-benzoic acid methyl ester (5.2 g, 93%) as a clear oil. 4,6,4′,6′-Tetramethoxy-biphenyl-2,2′-dicarboxylic acid dimethyl ester: 2-Bromo-3,5-dimethoxy-benzoic acid methyl ester (5.2 g) was dissolved in DMF (16 mL), and Cu powder (2.4 g) was added . After stirring at 150° C. for 3 days, the mixture was filtered and evaporated under vacuum. The crude material was subjected to silica gel chromatography using effluent of 30-60% ethyl acetate and hexanes. The fractions containing product were combined and the solvent was removed under reduced pressure to provide 4,6,4′,6′-tetramethoxy-biphenyl-2,2′-dicarboxylic acid dimethyl ester (2.5 g, 68%) as a clear oil. (6′-Hydroxymethyl-4,6,2′,4% tetramethoxy-biphenyl-2-yl)-methanol: 4,6,4′,6′-tetramethoxy-biphenyl-2,2′-dicarboxylic acid dimethyl ester (2.5 g) was dissolved in THF (96 mL), and 1M LiAlH4 in THF (9.6 mL) was added . After stirring at room temperature for overnight, the mixture was quenched with water and 2N HCl (24 mL) was added. The mixture was evaporated under vacuum and partitioned with DCM (300 mL) and water (200 mL). The organic layer was dried over Na2SO4 and crystallized with DCM to provide (6′-hydroxymethyl-4,6,2′,4′-tetramethoxy-biphenyl-2-yl)-methanol (1.7 g, 77%) as a pale blue white triclinic crystals. 6,6′-Bis-bromomethyl-2,4,2′,4′tetramethoxy-biphenyl: (6′-hydroxymethyl-4,6,2′,4′-tetramethoxy-biphenyl-2-yl)-methanol (779 mg) was dissolved in DCM (5.8 mL), and PBr3 (527 μl) was slowly added at 0° C. After stirring at 0° C. for 30 min. and at room temperature for 1 hour, H2O (40 mL) was added. The mixture was extracted with ether (1×, 50 mL). After the solvent was removed, the crude material was subjected to silica gel chromatography using effluent of 10-40% ethyl acetate and hexanes. The fractions containing product were combined and the solvent was removed under reduced pressure to provide 6,6′-bis-bromomethyl-2,4,2′,4′-tetramethoxy-biphenyl (700 mg, 65%) as a thick oil. 6,6′-Bis-bromomethyl-biphenyl-2,4,2′,4′-tetraol: 6,6′-bis-bromomethyl-2,4,2′,4′-tetramethoxy-biphenyl (685 mg) was dissolved in DCM (3.0 mL), and 1M BBr3 in DCM (16.4 mL) was slowly added. After stirring for 2 days, the mixture was poured on to ice and concentrated. The crude material was used for the next step without a further purification. 5-10-Dihydro-chromeno[5,4,3-cde]chromene-2,7-diol: The crude 6,6′-bis-bromomethyl-biphenyl-2,4,2′,4′-tetraol was dissolved in DMF (30 mL), and Cs2CO3 (1.9 g) was added. After stirring at room temperature for 1 hour, the mixture was partitioned with 1 N HCl (100 mL) and ethyl acetate (100 mL), and extracted with ethyl acetate (3×, 100 mL). After the solvent was removed, the crude material was subjected to silica gel chromatography using effluent of 10-15% methanol and DCM. The fractions containing product were combined and the solvent was removed under reduced pressure to provide 5-10-dihydro-chromeno[5,4,3-cde]chromene-2,7-diol (301 mg, 84%) as a white solid. Trifluoro-methanesulfonic acid 7-trifluoromethanesulfonyloxy-5,10-dihydro-chromeno[5,4,3-cde]chromen-2-yl ester: 5-10-Dihydro-chromeno[5,4,3-cde]chromene-2,7-diol (290 mg) was dissolved in DCM (12 mL), and Tf2O (1.2 mL) and pyridine (969 μl) were added. After stirring at room temperature for overnight, the mixture was partitioned with 2 N HCl (50 mL) and DCM (50 mL), and washed with 2 N HCl (2×50 mL) and saturated sodium bicarbonate (1×50 mL). After the solvent was removed, the resulting oil was subjected to silica gel chromatography using effluent of 0-30% ethyl acetate and hexanes. The fractions containing product were combined and the solvent was removed under reduced pressure to provide trifluoro-methanesulfonic acid 7-trifluoromethanesulfonyloxy-5,10-dihydro-chromeno[5,4,3-cde]chromen-2-yl ester (472 mg, 78%) as an off-white solid. (1-{2-[5-(7-{2-[1-(2-Methoxycarbonylamino-3-methyl-butyryl)-pyrrolidin-2-yl]-3H-imidazol-4-yl}-5,10-dihydro-chromeno[5,4,3-cde]chromen-2-yl)-1H-imidazol-2-yl]-pyrrolidine-1-carbonyl]-2-methyl-propyl)-carbamic acid methyl ester: Title compound was prepared according to the method employed to prepare (1-{2-[5-(2-{2-[1-(2-Methoxycarbonylamino-3-methyl-butyryl)-pyrrolidin-2-yl]-3H-imidazol-4-yl}-6-H-dibenzo[c,h]chromen-8-yl)-1H-imidazol-2-yl]-pyrrolidine-1-carbonyl}-2-methyl-propyl)-carbamic acid methyl ester, substituting trifluoro-methanesulfonic acid 7-trifluoromethane sulfonyloxy-5,10-dihydro-chromeno[5,4,3-cde]chromen-2-yl ester for trifluoro-methanesulfonic acid 2-trifluoromethanesulfonyloxy-6-H-dibenzo[c,h]chromen-8-yl ester.

1. customthe mixture was quenched with water and 2N HCl (24 mL)
2. additionwas added
3. customThe mixture was evaporated under vacuum
4. custompartitioned with DCM (300 mL) and water (200 mL)
5. dry with materialThe organic layer was dried over Na2SO4
6. customcrystallized with DCM