Chemical Constituents Of Reboulia Hemisphaerica And Brachythecium Rivulare

The bryophytes are taxonomically placed between the algae and the pteridophytes and more than 20000 species are known in the world.Bryophytes have important medicinal value.For thousands of years,the bryophytes have been used in folk remedies to cure various kinds of diseases such as cuts,bums,bacteriosis, tuberculosis,pneumonia,neurasthenia etc.Many terpeniods and aromatic compounds with novel skeletons or significant bioactivities have been obtained from mosses and liverworts,some of which are nice lead compounds in new drug research.Many studies indicate that the bryophyte components constitute a rich source of structually new and biologically active compounds.In recent years,with the spread of HIV,an increase in tumor,the emergence of drug-resistant and people's concerns about drug toxic or side effects,low toxicity and efficient development of new drugs is imminent.Chemical constituents from bryophytes possess the potential value of drug development in the above fields.In addition,traditional agriculture on the environment and resources has become an increasing concern about the negative impact.People's increasing demands for ecological agriculture are more strongly.The bryophytes have the important application value in this aspect.In this paper,a systematically phytochemical investigation of the chemical constituents of Reboulia hemisphaerica(linn.) raddi collected from Mount Yue-lu, Hunan Province,PR China was carried out,and led to yield 24 compounds,22 of which were identified,including ten bis(bibenzyl)s:marchantin C(Ⅰ),neomarchantin A(Ⅱ),riccardin B(Ⅲ),riccardin C(Ⅳ),marchantin A(Ⅴ),marchantin J(Ⅵ), pakyonol(Ⅶ),perrottetin E(Ⅷ),isoriccardin C(Ⅸ) and isomarchantin C(Ⅹ);one bibenzyl:lunulafin(Ⅺ);two flavones:apigenin-6,7,4'-trimethylether(Ⅻ) and apigenin (ⅩⅢ);two phenanthrenes:2-hydroxy-3,7-dimethoxyphenanthrene(ⅩⅣ) and 2-hydroxyl-3,5-dimethoxy phenanthrene(ⅩⅤ);one benzene derivative:allylhydroquinone (ⅩⅥ);two triterpenoids:α-zeorin(ⅩⅦ),6α,11α,22-trihydroxyhopane(ⅩⅧ); one sesquiterpenoid:rulepidol(ⅩⅨ);two steroids:stigmosterol arachidate(ⅩⅩ),β-sitosterol(ⅩⅪ) and mannitol(ⅩⅫ).The structures were elucidated on the basis of 1D and 2D-NMR,MS and IR spectroscopy.Among these compounds, compoundsⅥ,Ⅶ,Ⅷ,Ⅺ,Ⅻ,ⅩⅢ,ⅩⅣ,ⅩⅤ,ⅩⅥ,ⅩⅨ,andⅩⅩare first reported in R.hemisphaerica.Furthermore,we also investigated chemical constituents of Brachythecium rivulare B.S.G collected from West Tianmushan,Zhejiang Province,PR China.Six compounds were obtained by repeated chromatography and their structures were established by NMR together with IR and MS spectroscopy as ethyl orsellinate(ⅰ), 4-hydroxybenzaldehyde(ⅱ),loliolide(ⅲ),3′,3′″-binaringenin(ⅳ),ursolic acid(ⅴ),β-sitosterol(ⅵ),diploptene(ⅶ).Seven compounds were all isolated from this species for the first time.