preferred_name: spermine(out) + n H(+)(in) => spermine(in) + n H(+)(out)
preferred_name_lc: spermine(out) + n h(+)(in) => spermine(in) + n h(+)(out)
label: spermine(out) + n H(+)(in) => spermine(in) + n H(+)(out)
label_lc: spermine(out) + n h(+)(in) => spermine(in) + n h(+)(out)