Reagent for protection of amino groups as benzylsulfonamides which can be cleaved reductively, e.g. Na/NH3, Raney Ni/H2: J. Am. Chem. Soc., 79, 639, 645 (1957), or by photolysis: Tetrahedron Lett., 1029 (1979). Alcohols can also be protected, e.g. in the