Twelve new 5-[(5-trifluoromethyl-5-hydroxy-4,5-dihydro-1H-pyrazol-1-yl)-1-propan-1-one-3-yl]-2-methyl-7-trifluoromethylpyrazolo[1,5-a]pyrimidines were prepared by cyclocondensation between 2-methyl-7-trifluoromethylpyrazolo[1,5-a]pyrimidine-5-propanoyl hydrazide derived from 2-methyl-5-(methylpropanoate-3-yl)-7-trifluoromethylpyrazolo[1,5-a]pyrimidine and a series of versatile 1,1,1-trifluoro-4-alkoxy-3-alken-2-ones [F3CC(O)C(R²)=C(R¹)OMe where R¹ = H, Me, (CH2)2CHCMe2, (CH2)2Ph, (CH2)2CO2Me, Ph, 4-MeC6H4, 4-MeOC6H4, EtO and R² = H; R¹, R² = -(CH2)4-, -(CH2)5-; R¹ = Ph and R² = Me]. The structures of new propionyl-spaced biheterocycles were derived from ¹H, 13C, and 19F nuclear magnetic resonance (NMR) spectroscopy and mass spectrometric (MS) data.
heterocycles; pyrazolo[1,5-a]pyrimidines; pyrazoles; levulinic acid
