Spiro-fused (C2)-azirino-(C4)-pyrazolones, a new heterocyclic system. Synthesis, spectroscopic studies and X-ray structure analysis

1. Holzer, W.
2. Claramunt, R.M.
3. Pérez-Torralba, M.
4. Guggi, D.
5. Brehmer, T.H.