Judith Wardlaw

Lusitanic Acid, Peristictic Acid and Verrucigeric Acid. Three New β-Orcinol Depsidones from the Lichens Relicina sydneyensis and Xanthoparmelia verrucigera

Three new β-orcinol depsidones belonging to the stictic acid chemosyndrome, namely peristictic acid (1,4-dihydroxy-10-methoxy-5,8-dimethyl-3,7-dioxo-1,3-dihydro-7H-isobenzofuro[4,5-b][1,4]benzodioxepin-11-carboxylic acid) (9), lusitanic acid (methyl 1,4-dihydroxy-10-methoxy-5,8-dimethyl-3,7-dioxo-1,3-dihydro-7H-isobenzofuro[4,5-b][1,4]benzodioxepin-11-carboxylate) (10) and verrucigeric acid (1,4-dihydroxy-11-hydroxymethyl-10-methoxy-5,8-dimethyl-3,7-dioxo-1,3-dihydro-7H-isobenzofuro[4,5-b][1,4]benzodioxepin-1,11-diyl hydrogen orthoacetate) (14) have been identified in the lichens Relicina sydneyensis and Xanthoparmelia verrucigera respectively. The structure of the new depsidones followed from a combination of partial syntheses, chromatographic comparisons and spectroscopic data.

Pigmentosin A, a New Naphthopyrone from the Lichen Hypotrachyna immaculata ∗

The new naphthopyrone, pigmentosin A 1, has been isolated from the lichen Hypotrachyna immaculata and its structure elucidated using multidimensional NMR spectroscopic methods, including high-field (600 MHz) gHMBC and gHMQC experiments. This compound is the first lichen metabolite known to contain a bisnaphthopyrone moiety in its structure.

2-Hydroxyvirensic Acid, a New Depsidone from the Lichen Sulcaria sulcata

The new depsidone 2-hydroxyvirensic acid (4-formyl-2,3,8-trihydroxy-1,6,9-trimethyl-11-oxo-11H-dibenzo[b,e][1,4]dioxepin-7-carboxylic acid) (6) has been isolated from a chemical race of the lichen Sulcaria sulcataand the structure (6) deduced from a combination of spectroscopic data.

Neotricone and norperistictic acid, two new depsidones from the lichen genus Phaeographis

Two new β-orcinol depsidones, neotricone (4,10-dihydroxy-5,8-dimethyl-3,7-dioxo-1,3-dihydro-7H-isobenzofuro[4,5-b][1,4]benzodioxepin-11-carboxylic acid) (2) and norperistictic acid (1,4,10-trihydroxy-5,8-dimethyl-3,7-dioxo-1,3-dihydro-7H-isobenzofuro[4,5-b][1,4]benzodioxepin-11-carboxylic acid) (4) have been identified in the lichens Phaeographis syngraphizans and P. neotricosa. The structure of the new depsidones followed from a combination of partial syntheses, chromatographic comparisons, and spectroscopic data.

Subvirensic Acid, a New Depsidone from the Lichen Flavoparmelia haysomii

The new depsidone subvirensic acid (4-formyl-3,8-dihydroxy-1,6-dimethyl-11-oxo-11H-dibenzo[b,e][1,4]di-oxepin-7-carboxylic acid) (7) has been isolated from the lichen Flavoparmelia haysomii and the structure deduced from a combination of spectroscopic data.

The Structure and Stereochemistry of Coronatoquinone, a New Pyranonaphthazarin from the Lichen Pseudocyphellaria coronata.

A new pyranonaphthazarin, coronatoquinone [(1S)-1,5,8,10-tetrahydroxy-7-methoxy-3-methyl-6,9-dihydro-1H-naphtho[2,3-c]pyran-6,9-dione] (1), has been isolated from the lichen Pseudocyphellaria coronata. The structure of coronatoquinone (1) was established by spectroscopic methods and its absolute configuration determined from chiroptical measurements.

Subpsoromic Acid, a New Depsidone from the Lichen Ocellularia praestans

The new depsidone subpsoromic acid (4-formyl-3-hydroxy-8-methoxy-1-methyl-11-oxo-11H-dibenzo[b,e]-[1,4]dioxepin-6-carboxylic acid) (6) has been isolated from the lichen Ocellularia praestans and the structure (6) deduced from a combination of spectroscopic data.