Practical Synthesis of an Orally Active CCR5 Antagonist, 7-{4-[2-(Butoxy)- ethoxy]phenyl}-N-(4-{[methyl(tetrahydro-2H-pyran-4-yl)amino]methyl}phenyl)- 1-propyl-2,3-dihydro-1H-1-benzazepine-4-carboxamide

A practical method of synthesizing 7-{4-[2-(butoxy)ethoxy]phenyl}-N-(4-{[methyl(tetrahydro-2H-pyran-4-yl)amino]methyl}phenyl)-1-propyl-2,3-dihydro-1H-1-benzazepine-4-carboxamide (8), an orally active CCR5 antagonist, has been developed. Methyl 7-bromo-1-propyl-2,3-dihydro-1H-1-benzazepine-4-caboxylate (14a) was synthesized in good yield by the esterification of 4-[(4-bromo-2-formylphenyl)(propyl)amino]butanoic acid (13) followed by an intramolecular Claisen type reaction with 28% sodium methoxide in dimethyl carbonate as a solvent in one pot. The Suzuki−Miyaura reaction of 14a and 1-bromo-4-(2-butoxyethoxy)benzene (10) followed by hydrolysis and amidation gave 8. A new inexpensive method without chromatographic purification was established.