D S Rycroft - Liverwort Chemistry

Dr DAVID S. RYCROFT

Liverwort chemistry and chemosystematics

Examples of liverworts studied and characteristic compounds observed

	Adelanthus decipiens	acetophenones naphthalenes (including wettsteins A & B)
	Cryptothallus mirabilis [PDF] (a chlorophyll-free relative of Aneura pinguis, the original source of pinguisone, the first pinguisane sesquiterpenoid)	15-acetoxypinguisone cyclocuparanol (relative stereochemistry now confirmed by synthesis: Srikrishna et al., 1999) [PDF]
	Herbertus aduncus	1,2-dihydroxyherberten-12-al
	Herbertus borealis	a herbertenolide ester (present as a minor component in Scottish but not Norwegian specimens)
	Plagiochila atlantica	plagiochiline C atlanticol
	Plagiochila carringtonii [PDF]	plagiochilines T and U (2,3-secoaromadendranes)
	Plagiochila exigua	3,4-dihydroxy-3´-methoxybibenzyl
	Plagiochila killarniensis	methyl everninate (one of the odour-impact compounds in the lichen 'oakmoss', Evernia prunastri, used in perfumery) killarniensolide methyl orsellinates 9,10-dihydrophenanthrenes
	Plagiochila porelloides	plagiochiline V (a 2,3-secoaromadendrane)
	Plagiochila spinulosa	9,10-dihydrophenanthrenes methyl 4-hydroxy-4´-O-methyllunularate methyl orsellinates

Scottish liverworts that we have investigated previously, and novel sesquiterpenoids that we have isolated from them, include:

Chiloscyphus polyanthos var. pallescens
chiloscypholone
Conocephalum conicum
conocephalenol
Porella platyphylla
pinguisanin
Saccogyna viticulosa
saccogynol
Frullania tamarisci
tamariscol

One of the polar constituents from Scapania undulata is the novel naphthalene derivative scapaniapyrone A. This was the first example of a lignan structure to be elucidated in liverworts and is of interest to studies of the evolution of biosynthetic pathways.
Connectivity arguments were used to prove the unusual carbon skeletons in these compounds.

Selected publications

D S Rycroft - Research Interests
Chemistry Staff