Methanesulfonyl chloride → ((1S,4S)-4-(2,5-dimethyl-1H-pyrrol-1-yl)-1-isopropylcyclopent-2-enyl)(3-(trifluoromethyl)-7,8-dihydro-1,6-naphthyridin-6(5H)-yl)methanone

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Reaction Steps

N-((1R,3S)-3-isopropyl-3-{[3-(trifluoromethyl)-7,8-dihydro-1,6-naphthyridin-6(5H)-yl]carbonyl}cyclopentyl)-N-[(cis-3S,4S)-3-methoxytetrahydro-2H-pyran-4-yl]amine, 1, is synthesized by sequentially coupling three building block compounds 4, 5 and 6 (Schemes 3, 4 and 5, below). An amidation reaction between 3-(trifluoromethyl)-5,6,7,8-tetrahydro-1,6-naphthyridine, 5, and (1S,4S)-4-(2,5-dimethyl-1H-pyrrol-1-yl)1-isopropylcyclopent-2-ene-1-carboxylic acid, 4, is carried out in the presence of methanesulfonyl chloride to afford 6-{[(1S,4S)-4-(2,5-dimethyl-1H-pyrrol-1-yl)-1-isopropylcyclopent-2-en-1-yl]carbonyl}-3-(trifluoromethyl)-5,6,7,8-tetrahydro-1,6-naphthyridine. Deprotection of the pyrrole group was carried out at this stage using hydroxylamine as a through process to provide an amine salt. The amine salt and (3R)-3-methoxytetrahydro-4H-pyran-4-one, 6, are coupled through reductive amination, in the presence of a tributylamine buffer, and with NaBH(OAc)3 to afford (3S,4S)-N-((1S,4S)-4-isopropyl-4-{[3-(trifluoromethyl)-7,8-dihydro-1,6-naphthyridin-6(5H)-yl]carbonyl}cyclopent-2-en-1-yl)-3-methoxytetrahydro-2H-pyran-4-amine, 2. The cyclopentene moiety of compound 2 was then hydrogenated to form free base compound 1.

Provenance & Evidence