Isocalamenenes from the Liverwort Bazzania tridens

Four new sesquiterpenoids, 1,4-trans-6-hydroxyisocalamenene; 1,4-trans-6-methoxyisocalamenene; (+)-aristol-9-en- 12β-ol, and eudesm-4(15)-en-6β-acetoxy-7β-ol, were isolated from Bazzania tridens, a liverwort species. Their structures were identified by means of spectroscopic methods. The two isocalamenenes are derived from a methyl rearrangement of the calamenene skeleton.     

Tridensenal,A Sesquiterpene of Novel Skeleton from the Taiwanese Liverwort Bazzania Tridens

The sesquiterpene aldehyde, tridensenal, of previously unknown skeleton was isolated from the Taiwanese liverwort Bazzania tridens. The structure of tridensenal was elucidated on the basis of spectral data and proved by synthesis of the diastereomeric mixture.     

Rearranged Calamenene and Eudesmane Sesquiterpenoids from two Chinese Liverworts

Four novel rearranged calamenene sesquiterpenoids, 1 – 4 , and two eudesmane sesquiterpenoids, 5 and 6 , were isolated from the Chinese liverworts Chiloscyphus polyanthus (L.) and Bazzania japonica S. (Lac .) Lindb . Their structures and relative configurations were determined by chemical derivatization and in‐depth spectroscopic methods, especially 1D‐ and 2D‐NMR as well as HR‐MS analyses.     

Cytotoxic and apoptosis-inducing ent-kaurane-type diterpenoids from the Japanese liverwort Jungermannia truncata NEES

Five new ent-kaurane-type diterpenoids and a new gymnomitrane (=barbatane)-type sesquiterpenoid have been isolated from the Japanese liverwort Jungermannia truncata NEES, together with twelve previously known ent-kaurane-type diterpenoids. The structures of the new compounds were elucidated by two-dimensional (2D) NMR experiments and chemical reaction. Some of the isolated compounds showed cytotoxicity against human leukemia cell lines and induced apoptosis.     

Two New Sesquiterpenoids from the Rhizomes of Curcuma xanthorrhiza

Zedoardiol ( 1 ), a new furanoguaiane sesquiterpenoid, and 3,4‐dihydroxybisabola‐1,10‐diene ( 2 ), a new naturally occurring bisabolane sesquiterpenoid, together with six known compounds, were isolated from Curcuma xanthorrhiza Roxb . Their structures were determined on the basis of comprehensive spectroscopic analyses, mainly 1D‐ and 2D‐NMR, MS, IR and X‐ray single‐crystal diffraction. Herein, the isolation and structure elucidation of the compounds are described.     

Two new steroid glycosides and a new sesquiterpenoid glycoside from the underground parts of Trillium kamtschaticum

Two new steroid glycosides, named trikamsterosides A and B, and a new sesquiterpenoid glycoside named trikamsesuquiside A were isolated from the underground parts of Trillium kamtschaticum PALL. along with 18 known compounds comprising 12 steroids, one sesquiterpenoid glycoside, one phenylpropanoid, one flavonoid glycoside, and three phenylpropanoid sucrose esters. Their chemical structures were determined on the basis of spectroscopic data and chemical evidence. Among them, one phenylpropanoid sucrose ester showed almost the same radical-scavenging effect on 1,1-diphenyl-2-picrylhydrazyl as that of alpha-tocopherol.     

Terpenoids and aromatic compounds from the New Zealand liverworts Plagiochila, Schistochila, and Heteroscyphus species

A new clerodane- and two new ent-rosane-type diterpenoids have been isolated from the New Zealand liverworts Heteroscyphus billardierii and Plagiochila deltoidea, respectively. The known bisbibenzyl compounds and acetophenones have also been isolated from Schistochila glaucescens and Plagiochila fasciculata. Their structures were established by extensive NMR techniques. Chemosystematics of the Plagiochila species have been discussed.     

Glycosides of Atractylodes japonica

From the water-soluble portion of the methanol extract of the fresh rhizome of Atractylodes japonica, five new sesquiterpenoid glycosides, including a compound having a secoguaiane skeleton, and a new aromatic compound glycoside were isolated together with ten known compounds. Their structures were clarified by spectral investigation.     

Terpenoids from the liverwort Chandonanthus hirtellus

A new bicyclogermacrane sesquiterpenoid, two new cembrane diterpenoids and five new dolabellane diterpenoids, along with known terpenoids, have been isolated from the Malaysian liverwort Chandonanthus hirtellus. The structures of the new compounds were established by spectroscopic and chemical methods in addition to X-ray crystallographic studies.     

New megastigmane glycoside and aromadendrane derivative from the aerial part of Piper elongatum

A new megastigmane glycoside, called pipeloside A, and a new aromadendrane type sesquiterpenoid, pipelol A, were isolated from the MeOH extract of the aerial part of Piper elongatum VAHL. along with a known megastigmane glycoside, byzantionoside B. The structures of these compounds were elucidated on the basis of spectroscopic data and chemical evidence.     

青蒿素及其一类物结构和合成的研究——Ⅸ.全合成青蒿素中若干关键化合物的合成

青蒿素是一个含有过氧基团的新型倍半萜内酯~([1]),它具有突出的抗疟作用~([2])。本文报道     

New chroman derivatives from the Japanese liverworts Metacalypogeia cordifolia and Cephalozia otaruensis.

The diethyl ether extract of the Japanese liverwort Metacalypogeia cordifolia yielded five new chroman type derivatives in addition to known sesquiterpenoids. One of the new chroman derivatives was also isolated from the ether extract of another liverwort, Cephalozia otaruensis. Their structures were established by extensive two dimensional (2D) NMR techniques and chemical evidence. They were shown to be 2,2-dimethyl-7-(3-methyl-2-butenyl)-chroman derivatives. This was the first example of the isolation of the chroman-type compounds, although various types of aromatic compounds have been isolated from liverworts.     

Optically active bisbibenzyls from Bazzania trilobata: isolation and stereochemical analysis by chromatographic, chiroptical, and computational methods

Bazzanin S, a new chlorinated bisbibenzyl of the isoplagiochin D type, as well as isoplagiochin D itself were isolated from the liverwort Bazzania trilobata. The structure of bazzanin S was elucidated based on extensive NMR spectral evidence and by mass spectrometry. Both macrocyclic compounds, bazzanin S and isoplagiochin D, as well as previously reported bazzanins exhibit optical activity, but are not enantiopure in nature. The enantiomeric ratios of a broad array of different cyclic bisbibenzyls, isoplagiochin D, bazzanins A-C and F-J, and bazzanin S, were determined by HPLC on a chiral phase. Exemplarily for the halogen-free parent compound isoplagiochin D, elucidation of the absolute configuration was achieved by quantum chemical CD calculations.     

Diversity of Ligularia kanaitzensis in sesquiterpenoid composition and neutral DNA sequences

Twenty-six eremophilane-type sesquiterpenoids, including six new compounds, were isolated from the title species. One of the new compounds, kanaitzensol, suggested the presence of an enzyme for the conversion of eremophil-7(11)-en-8-one derivative to furanoeremophilanes. The plant was collected at 15 locations in Yunnan Province of China and found to be diverse with respect to its sesquiterpenoid composition. DNA sequencing also revealed a large intraspecific diversity of the plant.     

Chemical Constituents from the Leaves of Zanthoxylum Schinifolium

cis‐Fagaramide ( 1 ), a new amide, together with fifty known compounds, have been isolated from the leaves of Zanthoxylum schinifolium. These known compounds include twenty‐one coumarins, eleven alkaloids, one furan, four benzenoids, three chlorophylls, four triterpenoids, one diterpenoid, one sesquiterpenoid, and four steroids. The structures of these compounds were determined by means of spectral analyses.     

Spicachlorantins G-J, new lindenane sesquiterpenoid dimers from the roots of Chloranthus spicatus

Four new lindenane sesquiterpenoid dimers, spicachlorantins G-J (1-4), were isolated from the roots of Chloranthus spicatus together with seven known compounds, including chloramultilide A, shizukaol B, shizukaol D, shizukaol F, shizukaol P, chlorahololide D, and cycloshizukaol A. The planar structures of the new compounds were established by 1D-, 2D-NMR, and MS analyses. The absolute configurations of these compounds were determined by analyzing rotating Overhauser enhancement and exchange spectroscopy (ROESY) and circular dichroism (CD) spectra.     

A new diterpenoid glucoside and two new diterpenoids from the fruit of Vitex agnus-castus

A new labdane-type diterpenoid glucoside and two new labdane-type diterpenoids were isolated from the fruit (chasteberry) of Vitex agnus-castus L. (Verbenaceae) along with 14 known compounds comprising seven labdane-type diterpenoids, one halimane-type diterpenoid, two oleanane-type triterpenoids, two ursane-type triterpenoids, one aromadendrane-type sesquiterpenoid, and one flavonoid. Their structures were characterized on the basis of spectroscopic data as well as chemical evidence. Furthermore, the antioxidative activities of the flavonoid were evaluated using five different analyses.     

Pubescone,a Novel 11(7→6)Abeo‐14‐norcarabrane Sesquiterpenoid from Siegesbeckia pubescens

The phytochemical investigation of the aerial parts of Siegesbeckia pubescens L. yielded 16 sesquiterpenoids, including a novel 11(7→6)abeo‐14‐norcarabrane sesquiterpenoid, pubescone ( 1 ), and a new germacrane sesquiterpene, 5 . The molecular structures of the isolated compounds were elucidated on the basis of extensive spectroscopic analysis, including 1D‐ and 2D‐NMR.     

Structures of new sesquiterpenoids from Farfarae Flos

Two new bisabolane-type sesquiterpenoids, (3R,4R,6S)-3,4-epoxybisabola-7(14),10-dien-2-one and (1R,3R,4R,5S,6S)-1-acetoxy-8-angeloyloxy-3,4-epoxy-5-hydroxybisabola-7(14),10-dien-2-one, and a new oplopane-type sesquiterpenoid, 14(R)-hydroxy-7beta-isovaleroyloxyoplop-8(10)-en-2-one, were isolated from Farfarae Flos along with three known compounds. The structures of these compounds were elucidated on the basis of spectroscopic evidence.     

Two New Diterpenoid Glucosides from Clerodendrathus spicatus

Two new diterpenoid glucosides, clerodendranthusides B and C ( 1 and 2 , resp.), together with 16 known compounds, comprising four lignans, five miscellaneous phenylpropanoids, two flavonoids, one sesquiterpenoid glycoside, two triterpenoid glycosides, one megastigmane, as well as one anthraquinone, were isolated from the 50% EtOH extract of the whole plants of Clerodendrathus spicatus. Their structures were elucidated by chemical and spectroscopic methods.