V. Herout

Contribution to the chemotaxonomy of some european Petasites species

Abstract Thin-layer chromatography of certain chemical components of some species of Petasites can be used for quick and reliable identification of non-flowering individuals and interspecific hybrids. The substances are: furanopetasin in P. hybridus (L.) Gaertn., Meyer et Scherb., petasalbin in P. albus (L.) Gaertn., and kablicin in P. kablikianus Tausch. ex Bercht. The phylogenetic position of P. kablikianus is discussed and it is concluded that this taxon should be considered as an independent species of hybrid origin, which underwent a speciation process of its own. Evidence is presented concerning the occurrence of two chemovars for P. hybridus and P. albus.

Isolation and the structure of deoxopinguisone from the liverwort Ptilidium ciliare

Abstract A pure substance has been isolated from the liverwort Ptilidium ciliare of composition C 15 H 22 O. On the basis of the correlation of its IR and PMR spectra with those of pinguisone (I), it has been assigned structure of deoxopinguisone (II). This was confirmed by comparison with synthetic deoxopinguisone prepared from authentic pinguisone isolated from Aneura pinguis .

Terpenoids of the Petasites paradoxus and Petasites kablikianus in relation to their phylogeny

Abstract In addition to a hydrocarbon fraction identical with those of other Petasites species, the light petroleum extract of Petasites paradoxus contained: kablicin, angelyljaponicin, kablikopetasin, furoeremophilane and a hitherto unidentified triterpenic alcohol C 30 H 50 O. These substances are identical with those encountered in Petasites kablikianus . The assumed parallel phylogenetic origin of both species, and their hybrid origin from the same parent taxa, seems to be confirmed.

Polypodoaurein, a new phytoecdysone from Polypodium aureum L.

Abstract A new phytoecdysone was isolated from Polypodium aureum L. and its structure determined as 25- O -methylecdysterone.

Structure of isolaserolide from Laser trilobum

Abstract The structure I has been deduced for isolaserolide on the basis of its PMR spectrum and the chemical correlation with laserolide (II). Isolaserolide is the first elemanolide isolated from the Umbelliferae.