Ure. Water was added and the mixture extracted with ethyl acetate (20 mL). The resulting PDE4 Purity & Documentation combined organic layer was washed with brine, dried more than Na2SO4 and concentrated. The crude solution was purified by prep. HPLC to afford solution (35 mg, 23 ) as white strong. 1H NMR (400 MHz, DMSO-d6) (ppm): 11.17 (s, 1H), 8.72 (s, 1H), 7.98 (d, 1H, J= 8.8 Hz), 7. 89 (d, 1H, J= 8.0 Hz), 7.84 (d, 1H, J= 8.0 Hz), 6.71 (d, 1H, J= 2.0 Hz), 6.18 (d, 1H, J= three.eight Hz), five.48 (s, 1H), 5.13.16 (m, 1H), 3.27 (s, 3H), 2.36 (brs, 3H), 2.16 (s, 3H), 1.43.45 (m, 3H); ESIMS m/z (M+1): 423.two; LCMS: 99.66 ; HPLC purity: 94.67 . 4-(Cyano(6-(trifluoromethyl)pyridin-3-yl)methyl)-3-methyl-N-(1-(5methylisoxazol-3-yl) ethyl)-1H-pyrrole-2-carboxamide (70).–Boc anhydride (236 mg, 0.108 mmol) was added to a stirred solution of 227 (400 mg, 0.98 mmol), triethylamine (0.two mL, 1.47 mmol) and DMAP (12 mg, 0.09 mmol) in CH2Cl2 (20 mL) at RT and continued for four h. Following completion of reaction (monitored by TLC), water was added and also the reaction mixture extracted with CH2Cl2 (20 mL). The combined organic layer was dried more than Na2SO4 and concentrated. The resulting concentrated product was purified by column chromatography utilizing 00 ethyl acetate in petroleum ether to afford tert-butyl 3methyl-2-((1-(5-methylisoxazol-3-yl)ethyl)carbamoyl)-4-(6-(trifluoromethyl)pyridine-3carbonyl)-1H-pyrrole-1-carboxylate (450 mg, 90 ) as yellow liquid. ESIMS m/z(M+1): 507.two. Solution was utilized without having purification. Sodium borohydride (67 mg, 1.78 mmol) was added portionwise to a stirred solution of your above Boc-pyrrole intermediate (0.45 g, 0.89 mmol) in ethanol (10 mL) at 0 plus the reaction mixture was stirred for 1 h at RT. The reaction mixture was concentrated beneath decreased pressure. Water (10 mL) was added to concentrated product and the mixture extracted with ethyl acetate (20 mL). The resulting combined organic layer was washed with brine, dried more than Na2SO4 and concentrated to afford tert-butyl 4-(hydroxy(6(trifluoromethyl)pyridin-3-yl)methyl)-3-methyl-2-((1-(5-methyl isoxazol-3yl)ethyl)carbamoyl)-1H-pyrrole-1-carboxylate (228) (0.4 g, 89 ). ESIMS m/z(M+1): 509.2. Item was utilised without further purification. TMSCN (78 mg, 0.79 mmol) was added to a stirred option of 228 (400 mg, 0.79 mmol) and tris(pentaflurophenyl)borane (20 mg, 0.04 mmol) in acetonitrile (four mL) at RT. Stirring was continued for eight h at RT. Just after completion of reaction (by TLC), reaction mixture was concentrated to afford tert-butyl 4-(cyano(6-(trifluoromethyl)pyridin-3-yl)methyl)-3methyl-2-((1-(5-methylisoxazol-3-yl)ethyl) carbamoyl)-1H-pyrrole-1-carboxylate (100 mg, 25 ). ESIMS m/z(M+1): 518.two. Solution was applied without the need of further purification. 4.5N HCl in dioxane (two mL) was added to a stirred option in the above Boc cyano pyrrole intermediate (one hundred mg, 0.19 mmol) in dioxane (two mL) at 0 and stirring continued for 2 h at RT. Just after completion of reaction (monitored by TLC), reaction mixture was concentrated after which dissolved in ethyl acetate (ten mL) and washed with sodium bicarbonate resolution (ten mL). The separated organic layer was dried more than Na2SO4, concentrated and purified byJ Med Chem. Met MedChemExpress Author manuscript; accessible in PMC 2022 Might 13.Author Manuscript Author Manuscript Author Manuscript Author ManuscriptPalmer et al.Pagecolumn chromatography making use of 00 ethyl acetate in petroleum ether to afford title compound (20 mg, 25 ). 1H NMR (400 MHz, CDCl3) (ppm): 9.54 (s, 1H), 8.75 (s, 1H), 7.91 (d, 1H, J= 8.4 Hz), 7.75 (d, 1H, J=.
