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Notes on the chemistry of some lichens, including four species of ...

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44 John. A. Elix and Tor Tønsberg GRAPHIS SCRIPTA 16 (2004)<br />

previous accounts <strong>of</strong> <strong>the</strong> chemical c<strong>on</strong>stituents<br />

<strong>of</strong> this <strong>species</strong> (Leuckert et al. 1995), up to <strong>four</strong><br />

dibenz<strong>of</strong>urans are listed.<br />

Specimen examined: Norway. Rogaland:<br />

Sauda, 2003, Tønsberg 31824 (BG).<br />

Lepraria multiacida Aptroot<br />

C<strong>on</strong>tains: atranorin (major), stictic acid<br />

(minor), c<strong>on</strong>stictic acid (minor), salazinic acid<br />

(trace), cryptostictic acid (trace), norstictic acid<br />

(trace), 3,7-di-O-methylstrepsilin (minor),<br />

strepsilin (trace),7-O-methylstrepsilin (trace),<br />

toge<strong>the</strong>r with traces <strong>of</strong> a number <strong>of</strong> o<strong>the</strong>r<br />

dibenz<strong>of</strong>urans.<br />

Note. 3,7-di-O-methylstrepsilin and 7-Omethylstrepsilin<br />

have not previously been<br />

reported as occurring in nature. Strepsilin and<br />

related compounds are new to Lepraria (see<br />

also below under L. xerophila).<br />

Specimen examined: Brazil. Minas Gerais:<br />

Catas Altas, 1997, Aptroot 40640 a40 (ABL<br />

isotype).<br />

Lepraria vouauxii (Hue) R.C.Harris<br />

C<strong>on</strong>tains: pannaric acid 6-methyl ester (major),<br />

4-oxypannaric acid 6-methyl ester (minor), 4oxypannaric<br />

acid 2-methyl ester (trace),<br />

pannaric acid (trace), pannaric acid 2-methyl<br />

ester (trace to minor), methyl porphyrilate<br />

(trace to minor), ± porphyrilic acid (trace),<br />

± atranorin (trace.)<br />

Note. The two accessory substances were<br />

present in Nash 3872. In a previous account <strong>of</strong><br />

<strong>the</strong> chemical c<strong>on</strong>stituents <strong>of</strong> this <strong>species</strong><br />

(Leuckert et al. 1995), three dibenz<strong>of</strong>urans are<br />

listed.<br />

Specimens examined: USA. Ariz<strong>on</strong>a: Cochise<br />

Co., 1972, Nash 3872 (ASU); Santa Cruz Co.,<br />

1997, Biringer 53 (ASU).<br />

Lepraria xerophila Tønsberg (ined.)<br />

Chemotype I<br />

C<strong>on</strong>tains: pannaric acid 6-methyl ester (major),<br />

atranorin (minor), methyl porphyrilate (trace to<br />

minor), ± porphyrilic acid (trace), ± pannaric<br />

acid (trace), ± unknown dibenz<strong>of</strong>uran (trace).<br />

Specimens examined: Mexico. Baja California:<br />

1995, Nash 38224 (ASU). USA. California:<br />

Santa Barbara Co., San Miguel Island, 1998,<br />

Tønsberg 25399 (BG).<br />

Chemotype II<br />

C<strong>on</strong>tains: norascomatic acid (major), strepsilin<br />

(minor), isostrepsilic acid (minor), atranorin<br />

(minor) and chloroatranorin (minor).<br />

Specimens examined: USA. California: Santa<br />

Barbara Co., Santa Rosa Island, 1994, Nash<br />

32904 (3 samples tested: all identical<br />

chemically; ASU).<br />

Note. To our knowledge this is <strong>the</strong> first report<br />

<strong>of</strong> <strong>the</strong> dibenz<strong>of</strong>uran isostrepsilic acid from a<br />

lichen. It has previously been dem<strong>on</strong>strated<br />

<strong>on</strong>ly from <strong>the</strong> mycobi<strong>on</strong>t <strong>of</strong> Usnea orientalis<br />

Motyka grown under culture c<strong>on</strong>diti<strong>on</strong>s (K<strong>on</strong><br />

et al. 1997). The new <strong>species</strong>, L. xerophila, is<br />

widely distributed in <strong>the</strong> westernmost part <strong>of</strong><br />

<strong>the</strong> Greater S<strong>on</strong>oran Regi<strong>on</strong>.<br />

Pyrrhospora quernea (Dicks.) Körb.<br />

Chemotype I<br />

C<strong>on</strong>tains: thiophanic acid (major), isoartho<strong>the</strong>lin<br />

(submajor), 2,4,7-trichlor<strong>on</strong>orlichexanth<strong>on</strong>e<br />

(minor), 2,5-dichlor<strong>on</strong>orlichexanth<strong>on</strong>e<br />

(minor), 2,7-dichlor<strong>on</strong>orlichexanth<strong>on</strong>e (trace),<br />

artho<strong>the</strong>lin (trace).<br />

Note. Unfortunately 7-chloroemodin occurs<br />

very close to isoartho<strong>the</strong>lin <strong>on</strong> HPLC, so if it<br />

were present it would be swamped by <strong>the</strong><br />

latter.

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