Diisopropylethylamine → (2,4-dimethyl-oxazol-5-yl)-{(S)-3-[6-(6-methoxy-5-methyl-pyridin-3-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yloxy]-pyrrolidin-1-yl}-methanone

Participants

Reaction Steps

A mixture of 2,4-dimethyl-oxazole-5-carboxylic acid (36.4 mg, 0.258 mmol), HTBU (98 mg, 0.258 mmol), DIPEA (86p1, 0.49 mmol) in DMF (5 mL) was stirred at rt for 20 min. then a solution of 6-(6-methoxy-5-methyl-pyridin-3-yl)-4-((S)-pyrrolidin-3-yloxy)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidine (prepared in example 1, method 1b, step 2) (80 mg, 0.23 mmol) and DIPEA (86 μl, 0.49 mmol) in DMF (0.4 mL) was added. The reaction mixture was stirred 30 min at rt. The reaction mixture was directly purified by preparative reverse phase Gilson HPLC and subsequent neutralization of the combined fractions over PL-HCO3 MP gave (2,4-dimethyl-oxazol-5-yl)-{(S)-3-[6-(6-methoxy-5-methyl-pyridin-3-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yloxy]-pyrrolidin-1-yl}-methanone (91 mg, 84% yield) as a white lyophilized powder. 1H-NMR (400 MHz, methanol-d4, 298K) δ ppm 2.17 (s, 3H) 2.27-2.52 (m, 8H) 2.95-3.03 (m, 2H) 3.44-3.55 (m, 2H) 3.70-4.26 (m, 9H) 5.76-5.92 (m, 1H) 7.40 (br. s., 1H) 7.64 (br. s., 1H) 8.55-8.62 (m, 1H), LCMS: [M+H]+=465.2, Rt(1)=1.51 min.

Provenance & Evidence