Synthesis and primary antiviral activity evaluation of 3-hydrazono-5-nitro-2-indolinone derivatives

A series of 5-nitro-3-[(5-nonsubstituted/methyl-4-thiazolidinone-2-ylidene)hydrazono]-1H-2indolinones (3a-j and 4a-h) was synthesized by cyclization of 5-nitro-1H-indole-2,3-dione-3thiosemicarbazones (1a-k) with ethyl bromoacetate or ethyl 2-bromopropionate. The primary antiviral activities of the new hydrazonoindolinone derivatives, the previously reported 5-nitro-1H-indole-2,3-dione-3-thiosemicarbazones (1a-k) and 1-morpholino/piperidinomethyl-5-nitroindole-2,3-dione-3-thiosemicarbazones (2a-l) were evaluated against some pathogenic viruses in the Rega Institue for Medical Research, Belgium. Among the tested compounds, 1c, 2b and 3b afforded some weak activity against the yellow fever virus (YFV) in vero cells, whereas compounds 2b, 3a, 3f, 4e and 4f inhibited the growth of bovine viral diarrhea virus (BVDV) in MDBK CODA cells.