Definition of tosyl in English:


Pronunciation /ˈtäsəl/ /ˈtɑsəl/


  • as modifier Of or denoting the toluene-4-sulphonyl radical —SO₂C₆H₄CH₃, used in organic synthesis.

    ‘tosyl chloride’
    • ‘In all experiments superparamagnetic particles of 4.5-m diameter (Dynabeads, Dynal, Hamburg, Germany) exhibiting reactive tosyl groups on the surface were used as magnetic tweezers.’
    • ‘The choice of TsSePh, rather than a tosyl halide, as the precursor of tosyl radical is based on the greater stability of the resulting selenides with respect to elimination compared to the halides.’


1930s from German, from to(luol) and s(ulphon)yl.