PHENAZINE SYNTHESES. III.¹ MISCELLANEOUS PHENAZINES

Abstract

The present paper continues the illustration of the applicability to a wide variety of phenazines of the general method of ring closure through the nitro group (1). There are here described, in addition to the syntheses of various substituted phenazines, those of three compounds embodying another heterocyclic ring in addition to the pyrazine system. These compounds are shown in the following representation, in which the structures of two of these three compounds (II and VI) have been written as the angular isomers, on the reasonable assumption that ring closure of the corresponding intermediates (I and V) occurred across the double bond of the heterocyclic moiety. In the instance of IV, it is obvious that only one structure is possible. Cl 4n xaxzz/xz VZxn^xZ II 6-(4-ChIoro-2-mtroanilmo)quinoline 10-Chloropyrido

An Efficient Buchwald–Hartwig/Reductive Cyclization for the Scaffold Diversification of Halogenated Phenazines: Potent Antibacterial Targeting, Biofilm Eradication, and Prodrug Exploration

“…MP 149–151 °C, lit. 148–149 °C . Note: Compound has been previously reported (CAS 58476-65-6), but only melting point was found for comparison.…”

Potential Chemopreventive Agents Based on the Structure of the Lead Compound 2-Bromo-1-hydroxyphenazine, Isolated from Streptomyces Species, Strain CNS284

“…The compound was purified by silica gel column chromatography, eluting with ethyl acetate-hexane, 1:1. The compound was obtained a light brown solid (49 mg, 9.7%): mp 107–108 °C (lit49 mp 117 °C). IR (film) 3026, 2976, 2920, 1633, 1604, 1511, 1482, 1466, 1437 cm −1 ; 1 H NMR (300 MHz, CDCl 3 ) δ 8.24 (m, 2 H), 8.14 (d, J = 8.9 Hz, 1 H), 8.00 (s, 1 H), 7.81 (m, 2 H), 7.28 (d, J = 8.9 Hz, 1 H), 2.66 (s, 3 H); 13 C NMR (75 MHz, CDCl 3 ) δ 143.5, 143.1, 142.8, 142.2, 141.1, 133.4, 130.1, 129.8, 129.5, 129.4, 128.9, 127.5,22.1; EIMS m/z (rel intensity) 194 (M + , 100).…”

Phenazine Natural Products: Biosynthesis, Synthetic Analogues, and Biological Activity

“…Nucleophilic substitution of a 2-nitrophenyl halide with an aniline affords the corresponding 2-nitrodiphenylamine. The reaction conditions depend on the substitution pattern on the reagents and include normal base catalysis − or additional activation by copper metal, often referred to as Jourdan−Ullmann conditions (K 2 CO 3 , copper-bronze, neat or H 2 O) . Variations of Ullmann's reaction conditions have been reported by Denny and co-workers, who successfully applied anhydrous conditions implying CuCl/Cu, N- alkylmorpholine as a base, and high-boiling solvents such as butanediol. ,, This method was generally high-yielding except for very electron-deficient amines (8-aminoisoquinoline) 104 or sterically hindered anilines (e.g., 2-chloro-6-fluoroaniline) .…”