STRUCTURE DETERMINATION AND SYNTHESIS OF FLUORO-NISSL-GREEN - AN RNA-BINDING FLUOROCHROME

The isolation, structure determination, and total synthesis of Fluoro Nissl Green, a novel RNA-binding fluorochrome, are reported. Initially obtained: in only one part per 10(5), via a microwave-induced synthes is from m-phenylenediamine, the structure was determined by spectrosco pic methods to be 3,8-diamino-10H-quindoline. The proposed structure w as confirmed by a rational synthesis starting from m-phenylene diamine :and 2,4-dinitrobenzaldehyde. The key step employed a Friedlander reac tion to construct the quindoline ring system from 1-acetyl-6-(acetylam ino)-3-indolinone and 2-amino-4-(acetylamino)benzaldehyde. Histochemic al studies with synthetic Fluoro Nissl Green demonstrate selective sta ining of neuronal perikarya and nucleoli.