Preparation of pyrazolopyrimidines as anti-enterovirus compounds.

Abstract

The title compds. [I; A = (CH2)qCHRaRb; R1, R2 = H, halo, CN, NO2, alkyl; or R1 and R2 taken together is (CH2)r; R3, R4 = H, halo, CN, NO2, alkyl; R5, Ra, Rb = (un)substituted aryl, aralkyl, heteroaryl; m, n, o, p, r = 0 or 1; q = 0-2; provided that the sum of m, n, o, and p = 1, 2, 3, or 4], were prepd. Thus, reacting 4-chloro-1-phenyl-1H-pyrazolo[3,4-d]pyrimidine with 1-(diphenylmethyl)piperazine afforded 95% 4-(4-benzhydrylpiperazino)-1-phenyl-1H-pyrazolo[3,4-d]pyrimidine. The 5 of 42 prepd. compds. I were tested against enteroviruses and non-. All 5 pyrazolopyrimidine compds. showed antiviral activity against all enteroviruses tested (IC50 values less than 1 μM and as low as 0.085 μM). In particular, against COX-A24, -B2, -B3, or -B4. In contrast, these compds. showed little efficacy against the non-enteroviruses (Ic50 values higher than 25 μM). [on SciFinder(R)]