T. Eicher

Carboxylated α-pyrone derivatives and flavonoids from the liverwort Dumortiera hirsuta

Abstract Three new carboxylated α-pyrone derivatives, dumortins A-C, and a new flavone glycoside have been isolated from the liverwort, Dumortiera hirsuta , together with the known flavonoids, luteolin, luteolin -5-O-β- d -glucuronide and luteolin -7-O-β- d -glucuronide . The structures of the new α-pyrones were confirmed spectroscopically as 4-(3′,4′-dihydroxy- E -styryl)-6-carboxy-α-pyrone,4-[2-(3′,4′-dihydroxyphenyl)-ethyl]-6-carboxy-α-pyrone and 3-[1-hydroxy-2-(3′,4′-dihydroxyphenyl)-ethyl]-6-carboxy-α-pyrone. The new flavonoid was elucidated as luteolin -5-O-β- d -glucuronide-6″-methyl ester. The structures of dumortins A and B were confirmed by independent chemical synthesis.

Ten asulenes from Plagiochila longispina and Calypogeia azurea

Abstract From gametophytic tissues of the naturally grown foliose liverworts Plagiochila longispina and Calypogeia azurea and from in vitro cultures of C. azurea, 10 azulenes have been isolated, of which eight proved to be new natural products. Their structures were elucidated by means of spectroscopic methods and by independent synthesis.