Fluorescence quenching nitrodiarylethene analogs are useful in oligonucleotide conjugates and probes. These analogs, whose absorption spectra are substantially blue-shifted relatively to emission spectra of common fluorophores (such as fluorescein), do not need to rely on spectral overlap of quencher absorbance and fluorophore's emission for their quenching abilities. The oligonucleotide-quencher conjugates may be used in detection methods for nucleic acid targets.