The present application relates to dihydrofluorocarbonate reductase inhibitors and pharmaceutical preparations of dihydrofluorocarbonate reductase. It also refers to the use of existing inhibitors to treat parasitic infections, such as T. gondii, T. cruzi, P. falciparum, T. Bruce, or L. major. 1. Characteristic requirement 1: compound with formula structure (1) or pharmaceutically acceptable or antiseptic salts, wherein: R1 is h, tar c83331832626;cycloquilo C833238832626;Cycloquilo c833243183288o halogen; W is n or CR1 8312e, C (R2 cubic),O w-y is C = C (R3);Z is n or cr18311,2. The condition is that at least one of W and Z is n;R3,R830808,R83099,R8310,R8311th,R8322,R8313,R1831181 and r831222 are independent of H, acquilo c832135833126,cycloquilo C833238832626;Hydroxyl or fluorine, provided that there are at least four rivers,R3,R830808,R83099,R8310,R8311th,R8322,R8313 Sean h, if W is n, no,R3,R8310,R831181 is hydroxyl, if Z is n, there is no r83088,R83099,R8322,E r8313 is hydroxyl; r183044 is 5 to 10 members replaced or not replaced by arilo c8332683318321832083208320;La presente solicitud se refiere a inhibidores de la dihidrofolato reductasa y a preparaciones farmacéuticas de los mismos. Se refiere además a métodos de tratamiento de infecciones parasitarias, tales como infecciones por T. gondii, T. cruzi, P. falciparum, T. brucei o L. major, usando los inhibidores de la presente. Reivindicación 1: Un compuesto que tiene la estructura de fórmula (1) o una sal farmacéuticamente aceptable o profármaco del mismo, donde: R¹ es H, alquilo C₁₋₆, cicloalquilo C₃₋₆, cicloalquilalquilo C₄₋₈ o halógeno; W es N o CR¹⁸ e Y es C(R²R³), o W-Y es C=C(R³); y Z es N o CR¹⁷, con la condición de que al menos uno de W y Z sea N; R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, R¹⁷ y R¹⁸ se seleccionan independientemente de H, alquilo C₁₋₆, cicloalquilo C₃₋₆, hidroxilo o flúor; con la condición de que al menos cuatro de R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, y R⁹ sean H; si W es N, entonces ninguno de R², R³, R⁶