title: Liquid-phase synthesis of combinatorial libraries based on 7-trifluoromethyl-substituted pyrazolo[1,5-a]pyrimidine scaffold.
abstract: The parallel solution-phase synthesis of more than 2200 7-trifluoromethyl-substituted pyrazolo[1,5-a]pyrimidine and 4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidine carboxamides on a 50-100-mg scale has been accomplished. Key reactions include assembly of the pyrazolo[1,5-a]pyrimidine ring by condensation of 5-aminopyrazole derivatives with the corresponding trifluoromethyl-beta-diketones. The libraries from libraries were then obtained in good yields and purities using solution-phase acylation and reduction methodologies. Simple manual techniques for parallel reactions using special CombiSyn synthesizers were coupled with easy purification procedures (crystallization from the reaction mixtures) to give high-purity final products. The scope and limitations of the developed approach are discussed.
authors.affiliation: Zelinski Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky prospekt, 47, 119991, Moscow, Russian Federation.
authors.forename: Igor L
authors.initials: IL
authors.lastname: Dalinger
authors.forename: Irina A
authors.initials: IA
authors.lastname: Vatsadse
authors.forename: Svyatoslav A
authors.initials: SA
authors.lastname: Shevelev
authors.forename: Alexandre V
authors.initials: AV
authors.lastname: Ivachtchenko
mesh_terms: D020650:Combinatorial Chemistry Techniques / Q000379:methods*; D015195:Drug Design; D015394:Molecular Structure; D011720:Pyrazoles / Q000138:chemical synthesis* / Q000737:chemistry; D011743:Pyrimidines / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D011720:Pyrazoles; D011743:Pyrimidines