ausblenden:
Schlagwörter:
heterocycles; cyclotetramerization; macrocycles; photodimerization
Zusammenfassung:
The new cyclic quaterbenzoxazole 5 and -imidazole 8 have been synthesized by cyclization of 3-amino-2-hydroxybenzamide (4) and the ammonium salt of 2,3-diaminobenzoic acid (7), respectively, with polyphosphoric acid. Both compounds represent a new heterocyclic nine ring system, which can be built up from four identical (or different) benzo-x-azoles in a cyclic arrangement.