Polynuclear heterocyclic systems—II : Mass spectra of certain benzindole and dihydrobenzindole acids and esters☆

Abstract The mass spectra of compounds I to VIII have been studied. Structural assignments have been made for the major fragments, and pathways leading to their formation have been postulated by recognition of the appropriate metastable ions. The diagnostic value of the mass spectra in assigning the position of the ester function is discussed.