Ferns monochlamys

Several stable triterpenoid natural products containing 1,2,4-trioxolanes have been characterized, for example adian-5-ene ozonide (175) isolated from the fern Adiantum monochlamys <90CPB79,... 

Various fernanes are reported as constituents of some ferns, e.g. (+)-7- and (-)-8-femene as well as (-)-7,9(ll)-femadiene from Adiantum monochlamys and A pedatum (Pteridaceae). Hydroxylated derivatives are found in lichens such as reti-geric acid A in Lobaria retigera (Sticataceae) and some higher plants, e.g. (-)-7-femen-3p-ol in Rhododendron linearifolium (Ericaceae) and (-)-3p,lip-dihydroxy-8-femen-7-one in Euphorbia supina (Euphorbiaceae). 

Small amounts of the dextrorotatory parent hydrocarbon of the ten naturally abundant gammaceranes have been extracted from oil slate. 3-Hydroxy-derivatives such as (+)-16-gammacerene-3p-ol are constituents of the roots of bitter herb Picris hieracioides (Asteraceae). 22p-Hydroxy-30-nor-gammaceran-21-one is found in the Japanese fern Adiantum monochlamys. 

Ageta, H., K. Iwata, and T. Kasama Fern Constituents, Filicenols A and B, Tetrahymanol, and Isoadiantol B, Isolated from Adiantum monochlamys. 11th Symposium on the Chemistry of Natural Products, Kyoto, Oct. 1967, Symposium Papers, p. 306. 

Ageta, H., K. Shiojima, R. Kamaya, and K. Masuda Fern Constituent. Naturally Occurring Adian-5-ene Ozonide in the Leaves of Adiantum monochlamys and Oleandra wallichii. Tetrahedron Letters 1978, 899. 

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