Synthesis of 2,3-diazaphenothiazine. X. 7- and 8-nitroderivatives of 1- keto and of 4-keto-2,3-diazaphenothiazine and their mixtures of oxidation on 5
Duro, F.; Vittorio, F.; Pappalardo, F.; Ronsisvalle, G.
Il Farmaco; Edizione Scientifica 32(2): 106-115
1977
ISSN/ISBN: 0430-0920 PMID: 870338 Document Number: 113936
A description is given of the synthesis of 7- and 8-nitro-derivatives of 1-keto- and 4-keto-2,3-diazaphenothiazine, by cyclization with acids and hydrated alkaline sulfides (XIV) and (XV). Oxidation of these nitroderivatives (XI), (XII), (XVI) and (XVII) gives products corresponding to those obtained by oxidation of the heterocyclic S atom to sulfones (IV), (XIII), (VIII) and (XVIII). Nitration of 1-keto- and 4-keto-2,3-diazaphenothiazine (1) and (V) gives the 7-nitroderivatives with simultaneous oxidation of the sulfur to sulfoxide (II) and (VI); oxidation of these sulfoxides or sulfones gives the same products (IV) and (VIII) obtained by the methods described above. The same compounds are obtained also by nitration of 1-keto- and 4-keto-5,5-dihidroxy-2,3-diazaphenothiazine (III) and (VII).