Figure 3.
Selected region of ESI mass spectra of 3, 3(17,18O), 4, and 4(17,18O) (top to bottom, respectively). Additional peak intensities are shown at (m + 1)/z and (m + 2)/z in spectra of isotopically labeled samples.
Selected region of ESI mass spectra of 3, 3(17,18O), 4, and 4(17,18O) (top to bottom, respectively). Additional peak intensities are shown at (m + 1)/z and (m + 2)/z in spectra of isotopically labeled samples.