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

<strong>Notes</strong> on the chemistry of some lichens, including four species of 

Lepraria 

JOHN A. ELIX and TOR TØNSBERG 

Elix, J.A. & Tønsberg, T. 2004. <strong>Notes</strong> on the chemistry of some lichens, including four 

species of Lepraria. Graphis Scripta 16: 43–45. Stockholm. ISSN 0901-7593. 

Chrysothrix flavovirens, Lepraria diffusa, L. multiacida, L. vouauxii, L. xerophila 

Tønsberg ined., Pyrrhospora quernea, and Rhizocarpon leptolepis were investigated. 3,7- 

Di-O-methylstrepsilin and 7-O-methylstrepsilin found in Lepraria multiacida, isostrepsilic 

acid present in L. xerophila, and 2,4-dichloro-3-O-methylnorlichexanthone acid 

found in Pyrrhospora quernea have not previously been reported as occurring in nature. 

John A. Elix, Department of Chemistry, Faculty of Science, Australian National University, 

Canberra ACT 0200, Australia. Email: john.elix@anu.edu.au 

Tor Tønsberg, Museum of Botany, University of Bergen, Allégaten 41, N-5007 Bergen, 

Norway. Email: tor.tonsberg@bot.uib.no 

The chemistry of many lichen species is still 

poorly known, especially for those substances 

that occur in minor or trace amounts. Specimens 

of various crustose lichens considered 

by the second author to contain interesting constituents, 

were investigated in detail by the first 

author. Some of the results proved to be of 

particular interest. We list them briefly below. 

Material and methods 

The specimens studied are deposited in ABL, 

ASU, BG, and O. The analytical methods used 

(TLC and HPLC) have been described previously 

(Elix & Tønsberg 1999). Only phenolic 

substances were detected. Fatty acids and terpenoids 

were not determined. 

Chrysothrix flavovirens Tønsberg 

Contains: diffractaic acid (major), rhizocarpic 

acid (major), atranorin (minor), epanorin (trace). 

Note. Diffractaic acid corresponds to the unidentified 

substance mentioned by Laundon 

(1981) for sorediate forms of Chrysothrix 

chrysophthalma (P.James) P.James & 

J.R.Launon s. lat. and to the C. chrysophthalma 

unknown mentioned for C. chrysophthalma 

and C. flavovirens Tønsberg by Tønsberg 

(1992, 1994). 

Specimen examined: Norway. Østfold: Hvaler, 

Kirkøy, 1983, Tønsberg 7861 (BG). 

Lepraria diffusa var. chrysodetoides 

(J.R.Laundon) Kukwa 

Contains: 4-oxypannaric acid 2-methyl ester 

(major), 4-oxypannaric acid (minor), porphyrilic 

acid (minor), atranorin (trace), 

pannaric acid (trace), pannaric acid 2-methyl 

ester (trace), pannaric acid 6-methyl ester 

(trace), 2 unknown derivatives of 4-oxypannaric 

acid (both minor). 

Note. With the substances listed above, 

including those in minor and trace amounts as 

well as the two unknowns, we report a total of 

eight dibenzofurans for Lepraria diffusa. In

44 John. A. Elix and Tor Tønsberg GRAPHIS SCRIPTA 16 (2004) 

previous accounts of the chemical constituents 

of this species (Leuckert et al. 1995), up to four 

dibenzofurans are listed. 

Specimen examined: Norway. Rogaland: 

Sauda, 2003, Tønsberg 31824 (BG). 

Lepraria multiacida Aptroot 

Contains: atranorin (major), stictic acid 

(minor), constictic acid (minor), salazinic acid 

(trace), cryptostictic acid (trace), norstictic acid 

(trace), 3,7-di-O-methylstrepsilin (minor), 

strepsilin (trace),7-O-methylstrepsilin (trace), 

together with traces of a number of other 

dibenzofurans. 

Note. 3,7-di-O-methylstrepsilin and 7-Omethylstrepsilin 

have not previously been 

reported as occurring in nature. Strepsilin and 

related compounds are new to Lepraria (see 

also below under L. xerophila). 

Specimen examined: Brazil. Minas Gerais: 

Catas Altas, 1997, Aptroot 40640 a40 (ABL 

isotype). 

Lepraria vouauxii (Hue) R.C.Harris 

Contains: pannaric acid 6-methyl ester (major), 

4-oxypannaric acid 6-methyl ester (minor), 4oxypannaric 

acid 2-methyl ester (trace), 

pannaric acid (trace), pannaric acid 2-methyl 

ester (trace to minor), methyl porphyrilate 

(trace to minor), ± porphyrilic acid (trace), 

± atranorin (trace.) 

Note. The two accessory substances were 

present in Nash 3872. In a previous account of 

the chemical constituents of this species 

(Leuckert et al. 1995), three dibenzofurans are 

listed. 

Specimens examined: USA. Arizona: Cochise 

Co., 1972, Nash 3872 (ASU); Santa Cruz Co., 

1997, Biringer 53 (ASU). 

Lepraria xerophila Tønsberg (ined.) 

Chemotype I 

Contains: pannaric acid 6-methyl ester (major), 

atranorin (minor), methyl porphyrilate (trace to 

minor), ± porphyrilic acid (trace), ± pannaric 

acid (trace), ± unknown dibenzofuran (trace). 

Specimens examined: Mexico. Baja California: 

1995, Nash 38224 (ASU). USA. California: 

Santa Barbara Co., San Miguel Island, 1998, 

Tønsberg 25399 (BG). 

Chemotype II 

Contains: norascomatic acid (major), strepsilin 

(minor), isostrepsilic acid (minor), atranorin 

(minor) and chloroatranorin (minor). 

Specimens examined: USA. California: Santa 

Barbara Co., Santa Rosa Island, 1994, Nash 

32904 (3 samples tested: all identical 

chemically; ASU). 

Note. To our knowledge this is the first report 

of the dibenzofuran isostrepsilic acid from a 

lichen. It has previously been demonstrated 

only from the mycobiont of Usnea orientalis 

Motyka grown under culture conditions (Kon 

et al. 1997). The new species, L. xerophila, is 

widely distributed in the westernmost part of 

the Greater Sonoran Region. 

Pyrrhospora quernea (Dicks.) Körb. 

Chemotype I 

Contains: thiophanic acid (major), isoarthothelin 

(submajor), 2,4,7-trichloronorlichexanthone 

(minor), 2,5-dichloronorlichexanthone 

(minor), 2,7-dichloronorlichexanthone (trace), 

arthothelin (trace). 

Note. Unfortunately 7-chloroemodin occurs 

very close to isoarthothelin on HPLC, so if it 

were present it would be swamped by the 

latter.

GRAPHIS SCRIPTA 16 (2004) <strong>Notes</strong> on lichen chemistry including Lepraria 45 

Specimen examined: Denmark. Sønderjylland: 

1989, Jacobsen 6106 (BG). 

Chemotype II 

Contains: 6-O-methylarthothelin (major), 

arthothelin (major), thiophanic acid (minor), 

thiophaninic acid (minor), 2,4-dichloronorlichexanthone 

(minor), 7-chloroemodin (minor 

= orange pigment), atranorin (trace) and 4,5dichloronorlichexanthone 

(trace). 

Specimen examined: USA. Washington: San 

Juan Co., Lopez Island, 1998, Tønsberg 26950 

(BG). 

Chemotype III 

Contains: thuringione (major), arthothelin 

(major), thiophanic acid (minor), 2,4-dichloro- 

3-O-methylnorlichexanthone acid (minor), 2,4dichloronorlichexanthone 

(minor), 7-chloroemodin 

(minor = orange pigment), atranorin 

(trace), 4,5-dichloro-3-O-methylnorlichexanthone 

(trace) and 4,5-dichloronorlichexanthone (trace). 

Note. 2,4-dichloro-3-O-methylnorlichexanthone 

acid has not previously been reported as 

occurring in nature. 

Specimen examined: USA. California: San 

Luis Obispo Co., 1992, Tønsberg 18442 (BG). 

Rhizocarpon leptolepis Anzi 

Contains: friesiic acid (major). 

Note. The depsido-depsone friesiic acid was 

recently reported as a new substance from the 

lichen Hypocenomyce friesii (Elix et al. 2004) 

where it is the diagnostic substance (Timdal 

1984; as friesii unknown). According to 

Timdal (1984) this substance is also the 

diagnostic substance in H. caradocensis. 

Although we tested only one specimen of 

Rhizocarpon leptolepis, this substance may 

also prove to be a diagnostic constituent in this 

species. 

Specimen examined: Norway. Buskerud: 

Sigdal, 1987, Timdal 4929 (O). 

References 

Elix, J. A. & Tønsberg, T. 1999. <strong>Notes</strong> on the 

chemistry of some lichens from Norway. 

Graphis Scripta 10: 4-6. 

Elix, J. A., Tønsberg, T. & Wardlaw, J. H. 2004. 

The structure of friesiic acid. Bibliotheca 

Lichenologica 88: 103-109. 

Kon, Y., Iwashina, T., Kashiwadani, H., 

Wardlaw, J. H. & Elix, J. A. 1997. A new 

dibenzofuran, isostrepsilic acid, produced 

by cultured mycobiont of the lichenized 

ascomycete Usnea orientalis. Journal of 

Japanese Botany 72: 67-71. 

Laundon, J. R. 1981. The species of 

Chrysothrix. Lichenologist 13: 101-121. 

Leuckert, C., Kümmerling, H. & Wirth, V. 

1995. Chemotaxonomy of Lepraria Ach. 

and Leproloma Nyl. ex Crombie, with 

particular reference to Central Europe. 

Bibliotheca Lichenologica 58: 245-259. 

Timdal, E. 1984. The genus Hypocenomyce 

(Lecanorales, Lecideaceae), with special 

emphasis on the Norwegian and Swedish 

species. Nordic Journal of Botany 4: 83- 

108. 

Tønsberg, T. 1992. The sorediate and isidiate, 

corticolous, crustose lichens in Norway. 

Sommerfeltia 14: 1-331. 

Tønsberg, T. 1994. Chrysothrix flavovirens sp. 

nov. - the sorediate counterpart of C. 

chrysophthalma. Graphis Scripta 6: 31-33.

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