Phenazine analog

Rigidone 47, another sesquiterpene orf/io-quinone which is derived from the curcumenes 97, was isolated from Pseudopterogorgia rigida by Freyer and coworkers [33]. It is important to mention that the structure of rigidone was verified by preparation from an authentic sample of the phenazine analog, 48. Rigidone, 47, exhibited a moderate Microphage... 

The reactions of haloquinoxalines in which the halogen atom is bonded to the benzenoid ring have not been well studied, but by analogy with examples in the phenazine series it would seem probable that they are unlikely to be displaced with the same ease as those bonded directly to the heterocyclic ring. It is evident from the foregoing discussion that A-oxidation has a pronounced effect on their reactivity, and, by this means, considerable latitude in the specific functionalization of dihalo or polyhalo derivatives may be exercised. 

Analogous to other N-oxides of polynitrogen heterocyclic bases, quinoxaline 1-oxide and phenazine 9-oxides undergo quater-... 

Dinitroso-benzol (analog verhalt sich 1,2-Benzochinon-bis-oxim, S. 614) wird in 1 n athanolischer Schwefelsaure bei 0 V (vs. SCE) iiberwiegend zu 1,2-Diamino-benzol (51% d.Th.) reduziert, daneben fallt hauptsachlich 2,3-Diamino-phenazin (39% d.Th.) (s.S. 700)3 an. 

Similar chemistry was applied by Heeg and co-workers in their synthesis of substituted quinoxalines 244, which were prepared by condensation of diamine 243 with 1,2-dicarbonyl compounds <00JHC1273>. Vagg utilized analogous chemistry to synthesize phenazines as well as quinoxalines (Section 6.2.8.1). 

The preparation and structure of [Ru(phen)2(l,5,6,10-tetraazaphenanthrene)]Cl2 have been reported NMR spectroscopic data provide insight into the hydrophilic properties of the complex. The bpy-containing complexes [Ru(bpy)2(92)] + and [ Ru(bpy)2 2(M 92)] ((92) = dipyrido(2,3-a 2, 3"-/z)phenazine) were described earlier in the chapter.The analogous [Ru(phen)2(92)] and [ Ru(phen)2 2(M 92)]" have also been prepared and characterized, as has [ (phen)2Ru(/i-92) 3Ru] +. The electronic spectra exhibit intense MLCT bands in the visible region the electrochemical properties of the complexes have been investigated and for [ (phen)2Ru(/i-92) 3Ru], two sets of reduction waves centered on ligand (92) are separated by those assigned to phen reductions. ... 

Menge Azo-Verbindung neben 28% Octafluor-phenazin. Tetrafluor- und Dijiuor-azoben-zole werden analog hergestellt1. 

Although chemically and structurally quite different from phenazines, phenazinium salts can be prepared by analogous methods from A -substituted benzene-1,2-diamines. 

By analogy with other classes of substances of similar constitution, such as phenazine (I) and phenoxazine (II) ... 

Cyclic voltammetry in supercritical water-0.2 M NaHS04 [88] and ammonia-0.14 M CF3SO3K [88,332] of some organic compounds shows that this electroanalytical technique was applicable under these conditions. The behavior of phenazine in NH3 at —40°C and under supercritical conditions, for example, was analogous two reversible reductions were found in both cases [88]. Dimethyl carbonate has been prepared from CO and MeOH on anodic oxidation in a supercritical mixture of CO2 and MeOH [89]. 

DISAL donors have also been used in the preparation of phenazine natural products and analogs [199]. 

Biosynthesis, synthetic analogs, and biological activity of phenazine natural products 04CRV1663. 

The primary process for the oxidation by O2 - of dihydrophenazine and dihydro-lumiflavin must be analogous to that for PhNHNHPh (Scheme 7-14) to give the anion radicals of phenazine (Phen ) and lumiflavin (Fl ). These in turn react with O2 to give O2 - plus phenazine and lumiflavin, respectively the process is analogous to that for the anion radical of azobenzene (PhN NPh), The oxidation potentials (Ep,a) for PhN NPh, Phen - and Fl - in Me2SO are -1.1 V versus NHE, -0.9 V, and -0.6 V, respectively. Each value is sufficiently negative to reduce O2 to O2 - (-0.5 V versus NHE in Me2SO). Hence, the (O2 )-induced auto-oxidation of PhNHNHPh also is thermodynamically feasible for dihydrophenazine and dihydro-lumiflavin and does occur for these two model substrates of reduced flavoproteins (Table 7-3). Such an auto-oxidation reaction sequence may be relevant to the fractional yield of 02 - from the flavin-mediated activation of 02 ° and the auto-oxidation of xanthine [catalyzed by xanthine oxidase (XO), a flavoprotein]. ... 

Phenanzin-N-oxid wird in quantitativer Ausbeute mit Hydrazin und Palladium/Kohle zu Phenazin reduziert4. Analog entsteht aus 2-Chlor-phenazin-N-oxid mit Ruthe-nium/Kohle und Hydrazin ohne Enthalogenierung l-Chlor-phenazin3. 

Iodinin also showed no incorporation of deuteriated (168), (170), (171), or 1-hydroxyphenazine. On the other hand, the N-oxide (178), which was isolated from B. iodinum, showed efficient incorporation of deuteriated 1-hydroxyphenazine and l-carboxy[6,7,8,9- H4]phenazine (as 170). Further, the latter was incorporated without deuterium loss and thus its conversion into (178) is analogous to its conversion into pyocyanin (173). 

This two-step process is analogous to, but much more efficient than, the classic Wohl-Aue synthesis of phenazines [233]. The versatility of this approach has been demonstrated by the synthesis of 1-methoxyphenazine that can be obtained from two different pairs nitroarene-aniline , namely, nitrobenzene-wta-anisidine or weta-nitroanisole-aniline (Scheme 98) [84]. 

Analogous feeding experiments with Pseudomonas aureofaciens established that (87) but not (88) was utilised in the formation of 2-hydroxyphenazine-l-carboxylic acid (94) and 2-hydroxyphena-zine (95). These results were interpreted as showing that both of these phenazine metabolites (94 and 95) are metabolites of phenazine-1-carboxylic acid (87) and are formed as outlined above. 

Analogs in which the S atoms of thianthrene are replaced by C(H), N or O to give anthracene, phenazine and dibenzo-p-dioxin, respectively, are all planar molecules (Figure 3 and Table I). Compounds are bent if either or both of the atoms are S, Se or Te (Figure 3 and Table II). This difference depends both on the valency angle of the atoms and the fact that d orbitals are used in the bonding of S or S-like atoms. 

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