A new phenazine synthesis. The synthesis of griseoluteic acid, griseolutein A, and methyl diacetylgriseolutein B

Abstract

6-Carboxy-4'-methoxy-2-nitro

Synthesis of phenazines by Cu-catalyzed homocoupling of 2-halogen anilines in water

“…Among the catalysts investigated, complex 1 exhibited preferable catalytic activity in 53% yield ( 4 NBr to be the best one in 79% yield (Table 1, entries 15,16). Furthermore, the catalyst, base and PTC loading was then investigated, and it was observed that decreasing the amount of the catalyst, base or PTC resulted in lower yields (Table 1, entries 17e20).…”

Fluorine substituted non-symmetric phenazines: a new synthetic protocol from polyfluorinated azobenzenes

“…Within the protocols of the first type deserve to be mentioned: the dimerization of nitroso-arenes by Bamberger-Ham reaction, 10 the dimerization of anilines via Pd-Ag C-H activation 11 and the homocoupling of 2-iodoanilines catalysed by sulfonato-Cu(salen) complex. 12 Within those of second type, the reported synthetic approaches are: the historical Wohl-Aue by condensation of nitro aromatics and anilines, 13,14 the reductive cyclization of 2-nitrodiphenylamines by sodium borohydride in ethanolic sodium ethoxide solution, 15 the combination of 2-bromo-anilines with 2-bromo-nitrobenzenes via sequential Buchwald-reduction-Buchwald, 16 the reaction of 2-bromo-nitrobenzenes with anilines via Buchwald-Hartwig/reductive cyclization, 17 the condensation between a quinone and orthophenylenediamine 2,18 and the Rh-catalysed ortho-amination of azobenzenes with aryl azides. 19 Scheme 1.…”

A new 16-membered tetraene macrolide JBIR-100 from a newly identified Streptomyces species

“…HIL Y-9031725 [280] . Due to the interesting biological activities of naturally occurring phenazines [139,[323][324][325][326] , the synthesis of poly-substituted phenazines was developed by Holliman and co-workers [327] from the reductive cyclization of o-nitrodiphenylamines. However, the yield was poor due to the competitive cyclization.…”