preferred_name: tetrachloroethene + AH2 => trichloroethene + chloride + A + H(+)
preferred_name_lc: tetrachloroethene + ah2 => trichloroethene + chloride + a + h(+)
label: tetrachloroethene + AH2 => trichloroethene + chloride + A + H(+)
label_lc: tetrachloroethene + ah2 => trichloroethene + chloride + a + h(+)