
Aldehydic (-CHO) group has greater priority than keto group and nitro groups is always a prefix.
Root word of the given compound is hept, double bond is the primary suffix and aldehydic group becomes secondary suffix and keto and nitro groups are prefixes.
Hence, the correct IUPAC name of the given compound is
4-Methyl-6-nitro-3-oxohept-4-enal
