Spectrophotometric Studies of Polyporus cinnabarinus and Polyporus sanguineus

HPLC and NMR Studies of Phenoxazone Alkaloids from Pycnoporus Cinnabarinus

“…This is the first unequivocal structural assignment of cinnabarin (1) employing 2D NMR spectroscopy. extracted from the HPLC contour plot, displayed UV maxima (λ max ~435 nm) characteristic of the phenoxazone nucleus [3,6,12,13]. The IR spectrum, which was similar to that of 1, once again supported the presence of hydroxy and amine groups (3420 cm -1 ), together with the presence of carbonyl groups (1690 and 1660 cm -1 , C-8 (δ 129.0) and to C-9a (δ 128.2).…”

“…[2] and Coriolus sanguineus (Polystictus cinnabarinus) [5]. To date, approaches adopted to determine the structures of 1-3 have included the use of infrared and Raman spectroscopy, ultraviolet spectroscopy, polarographic reductions, together with various syntheses and degradations [3,[6][7][8]. Given that the phenoxazone alkaloid pigments 1-3 are known to be notoriously insoluble in most organic and aqueous solvents, it is not surprising that a successful strategy for the isolation, separation and unequivocal NMR assignment of these compounds has so far eluded researchers [9,10].…”

“…Investigations of related fungal species such as that collected from La Digue Island, Seychelles, have afforded new phenoxazone pigments [11]. In this case the total crude pigment mixture was methylated with methyl iodide (CH 3 I) in an effort to alter the solubility characteristics and subsequently chromatographed to yield o-acetyl cinnabarine (4), 2-amino-9-formylphenoxazone-1carbonic acid (5), 9-hydroxymethyl-2-methylaminophenoxazone-1-carbonic acid methyl ester (6), phenoxazone (7) and the phenoxazone ether, pycnosanguin (12) [11]. Ergosterol (9), 5,6dihydroergosterol (10) and ergosterol peroxide (11) were also isolated from the same fungus [11].…”

“…As part of the continuing research activities of the Marine and Terrestrial Natural Product (MATNAP) research group at RMIT University, which studies the chemistry and biological activities of terrestrial fungi, we examined the bright, red-orange, wood-rotting [3,6,12,13]. The IR spectrum supported the presence of hydroxy and amine moieties (3386 and 3270 cm -1 ), carbonyl groups (1676 and 1655 cm -1 ), and an unsaturated cyclic system (1598 and 1596 cm -1 ), again similar to that previously reported for 1 [9].…”