Synthesis of novel pyrazolo 3 4 h 1 6 naphthyridine spiro pyrazolo 3 4 h pyrimido 4 5 b 1 6 naphthyridine dipyrazolo 3 4 b 3 4 f 1 8 naphthyridine quinoxaline derivatives study of their side chain reactions and photophysical properties
