Diterpenoids from the japanese liverwort jungermannia INFUSCA in honour of professor G. H. Neil Towers 75TH birthday

Sesqui- and Diterpenoids from the Japanese Liverwort Jungermannia infusca

“…As the present acquisition contains cuparane-type sesquiterpenoids and clerodane- and labdane-type diterpenoids as the main components, it should be included in the fourth chemotype. Species belonging to the same genus of liverworts occasionally produce normal and enantiomeric terpenoids, and sometimes, the same species from different locations produces both enantiomers. − The present sample of J. infusca contained (+)-kolavelool ( 11 ) as the main component, while J. infusca collected in Kochi, Japan, contained (−)-kolavelool ( 33 ) . This is an interesting observation in relation to the biosynthesis of diterpenoids in Jungermannia species.…”

“…It is apparent that there are at least four chemotypes of J. infusca , − in which the following classes of compounds predominate: (i) kaurane-type, (ii) labdane- and clerodane-type, (iii) bis(bibenzyl)-type, and (iv) cuparane- and labdane-type. As the present acquisition contains cuparane-type sesquiterpenoids and clerodane- and labdane-type diterpenoids as the main components, it should be included in the fourth chemotype.…”

“…As they are a rich source of unique terpenoids and aromatic compounds, these substances may be useful as chemosystematic specific and generic markers. Pinguisane- and sacculatane-type terpenoids as well as bis(bibenzyls) have been repeatedly isolated from liverworts, while they are never found in higher plants. , Many species belonging to the family Jungermanniaceae (Hepaticae) contain diterpenoids of the clerodane-, labdane-, pimarane-, verrucosane-, and ent -kaurane-type as major constituents. − Particularly, Japanese and Taiwanese collections of the species Jungermannia infusca (Mitt.) Steph.…”

“…Steph. (Jungermanniaceae) have yielded diterpenoids, sesquiterpenoids, and aromatic compounds as the main components. , The distribution of the above-mentioned substances has been shown to be dependent on the plant collection location, and therefore four chemotypes have been established . Recently, we reported the constituents of J. infusca collected in Hyogo, Japan, which contains ent -kaurane-type diterpenoids as main components .…”

The impact of accessible surface on hydrogen bond formation

“…35 Second, an unusual-shaped molecule-the molecules shown in orange are related to each other by translation and to the ones in purple via a 2 1 screw axis (b, CSD refcode MAVRUW). 36 See insets for 2D chemical diagrams.…”