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Eight new 19-oxygenated ent-kaurane diterpenoids (1-8) were isolated from the aerial parts of Isodon pharicus. Their structures were determined by means of extensive spectroscopic techniques including interpretation of 1D and 2D NMR spectra. Selected compounds were evaluated for their cytotoxicity against NB4, A549, PC-3, MCF-7, and SH-SY5Y cell lines.

A phytochemical study of Isodon rubescens leaves led to the isolation of five new diterpenoids, isorubesins A-E ( 1- 5), and fifteen known diterpenoids. The structures of these new compounds were elucidated by spectroscopic evidence. Most of the diterpenoids were tested for cytotoxicity against NB4, A549, SHSY5Y, PC3, and MCF7 human tumor cells. Some of them showed potent inhibitory activity. Compound 5 is the first reported atisane-type diterpenoid from this plant.

Aim To study the chemical constituents of the aerial parts of Schisandra propinqua var. propinqua . Method Silica gel, C 18 reversed phase silica gel and HPLC were used. The structures were elucidated by extensive spectroscopic methods. Result Two new triterpenoids, propinic lactone A ( 1 ) with 3, 4- seco -cycloartane skeleton, and propinic lactone B ( 2 ) possessing 3, 4:9, 10- seco -cycloartane skeleton, together with a known typical cycloartane triterpenoid, schizandronic acid ( 3 ), have been isolated and identified. Conclusion These two new triterpenoids serve as two important bridge intermediates from cycloartane triterpenoids to Schisandra nortriterpenoids biogenetically.

Two new 19-oxygenated ent-kaurane diterpenoids, pharicinins D and E (1 and 2), together with an artifact, pharicinin D acetal (3) were isolated from the leaves of Isodon pharicus. Their structures were determined by 1D and 2D NMR spectroscopic analysis. All of them were evaluated for their cytotoxicity. (C) 2009 Jian Xin Pu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

Aim To study the chemical constituents of the aerial parts of Isodon pharicus. Methods Silica gel, C18 reversed phase silica gel and HPLC were used. The structures were elucidated by extensive spectroscopic methods (IR, UV, MS and NMR). Results Five ent-kaurane diterpenoids, pharicunins N–R (1–5), were isolated and identified. Conclusion All of the compounds are new.

Five (1-5) ent-kaurane diterpenoids and 17 other known ones, were isolated from the leaves and stems of Isodon sinuolata. Their structures were determined on the basis of spectroscopic methods including 1D and 2D NMR spectroscopic analysis. All compounds were evaluated for cytotoxicity against a small panel of cell lines. Some compounds exhibited significant cytotoxicity.

A class of C 29 triterpene dilactones ( 1 – 6 ) featuring 18(13→14)- abeo -schiartane skeleton have been isolated from the stems of Schisandra propinqua var. propinqua . The structures of new compounds, propindilactones K–O ( 1 – 5 ), were determined on the basis of comprehensive spectroscopic means. Biogenetic pathway of 1 – 6 was proposed and then chemically mimicked. The absolute stereochemistries of new compounds were established on biosynthetic consideration coupled with CD experiments. Compound 2 showed promising anti-HBV activity in vitro.

From the dried roots of Euphorbia nematocypha, eight new diterpenoids, with ent-atisane (i.e., 1–5) and isopimarane (i.e., 6–8) type skeletons, together with five known compounds, were isolated. The structures of these new compounds were elucidated by spectroscopic data. Compounds 1–8 were evaluated for their cytotoxicity against a small panel of human cancer cell lines.

Six new nortriterpenoids, propindilatones E-J (1-6), and two known (7, 8) schiartane-type nortriterpenoids were isolated from the stems of Schisandra propinqua var. propinqua. Their structures were elucidated by extensive spectroscopic analyses, and the structure of compound 4 was confirmed through single-crystal X-ray diffraction. The absolute configuration of compounds 1-3 was established using CD methods. Compounds 4-6 were noncytotoxic against K562, A549, and HT-29 human cancer cells.

Bisjaponins A (1) and B (2), two new dimeric ent-kaurane diterpenoids connected with a rare four-membered carbon ring, which was formed by [2+2] reaction, were isolated from the aerial parts of Isodon japonicus. Their structures were elucidated by the analysis of spectroscopic evidence including extensive 2D NMR and MS data. Both the compounds were inactive for their cytotoxicity against human tumor cell lines, K562 and HepG2.

Three new 6,7-seco-eni-kauranoids (1-3) were isolated and structures were elucidated from Isodon sculponeatus. Diterpenoids 1-3 possessing multicyclic skeletons formed via oxygen atoms are all unprecedented among ent-kauranes. Compound I displayed significant cytotoxic activity against K562, A549, and HepG2 human tumor cell lines, with IC50 values of 1.4, 2.3, and 2.0 mu M, respectively, equal to the positive control. Plausible pathways for the biosynthesis of I and 2 from one related diterpenoid were also postulated. (C) 2007 Elsevier Ltd. All rights reserved.

Two new 6,7-seco-ent-kaurane diterpenoids, isojaponins A (1) and B (2), together with 18 known ent-kaurane diterpenoids were isolated from the aerial parts of Isodon japonicus. The structures of the two new compounds were elucidated by extensive 1D- and 2D-NMR spectroscopic methods in combination with MS experiments.

Two new ent-kaurane diterpenoids, minheryins H (1) and I (2), were isolated from the leaves of Isodon henryi. Their structures were elucidated by means of spectroscopic analysis, including 2D NMR spectra.

Three biogenetically interesting ent-kaurane-derived metabolites, alboatisins A-C (1-3), featuring a C-13-oxygenated ent-atisane skeleton, have been isolated from the aerial parts of Isodon albopilosus. Their structures were determined on the basis of spectroscopic evidence. Compound 2 exhibited cytotoxicity against A549 and HT-29 human cancer cells, with IC50 values of 8.3 and 7.9 microM, respectively.

Ten new triterpenoids, schiglausins A-J (1-10), as well as four known compounds, were isolated from the stems of Schisandra glaucescens. Their structures were elucidated on the basis of spectroscopic methods, including extensive NMR spectra and CD experiment. Compound 8 was determined to be a norlanostane triterpenoid. The crystal structure of compound 1 has been determined using single-crystal X-ray analysis while its absolute configuration was assigned on the basis of the CD spectrum. All isolates were tested for their FXR agonistic and antagonistic effects.

Five new cycloartane triterpenoids, schiglausins K-O (1-5), including one hexanortriterpenoid (1) and one octanortriterpenoid (2), as well as two known compounds (6-7), were isolated from the stems of Schisandra glaucescens Diels. Their structures were elucidated on the basis of spectroscopic methods, including extensive NMR spectra. Compounds 2-7 were tested for their FXR agonistic and antagonistic effects. Compound 7 exhibited significant antagonistic effect against FXR with IC50 of 1.50 mu M. (C) 2012 Elsevier B.V. All rights reserved.

A phytochemical investigation of Isodon pharicus led to the isolation of a novel asymmetric ent-kauranoid dimer, bispseurata F (1), and three new diterpenoids, pliaricinins A-C (2-4). Their structures were elucidated by extensive spectroscopic analysis. Compound 1 features a unique linkage pattern of C-17 with C-11' to connect the two monomers. A possible biogenetic pathway of 1 was also proposed. Compounds 3 and 4 exhibited moderate inhibitory activity against NB4 and SH-SY5Y cell lines. (C 2009 Elsevier Ltd. All rights reserved.

Phytochemical investigation of the aerial parts of Isodon pharicus led to the isolation of 13 new ent-kaurane diterpenoids, compounds 1-13, together with 12 known analogues (14-25). The structures of the new compounds were determined by means of extensive spectroscopic techniques including interpretation of 1D and 2D NMR spectra. Selected compounds were evaluated for their cytotoxicity against NB4, A549, PC-3, MCF-7, and SH-SY5Y cell lines.

Chromatographic fractionation of the extract of Isodon henryi resulted in the isolation of seven new ENT-kaurane diterpenoids, named minheryins A-G (1-7), together with the six known ENT-kaurane diterpenoids leukamenin F (8), excisoidesin (9), leukamenin E (10), wangzaozin A (11), pseurata A (12), and racemosin A (13), which were elucidated by spectroscopic analysis. Compounds 7-13 were tested for their cytotoxicity against K562 and HepG2 cell lines, and they all exhibited significant activities with IC50 values

Two new tetrahydrofuran lignans, kadlongirins A and B (1, 2), a new cadinane-type sesquiterpenoid, 2,7-dihydroxy-11,12-dehydrocalamenene (3), together with seven known lignans, grandisin, fragransin B1, vladirol F, kadsuralignan C, otobaphenol, isoanwulignan, and 4-[4-(3,4-dimethoxyphenyl)-2,3-dimethylbutyl]-2-methoxy-phenol, were isolated from the leaves and stems of Kadsura longipedunculata. The structures of these new compounds were elucidated by spectroscopic methods. Compound 2 exhibited weak anti-human immunodeficiency virus-1 activity with an EC50 value of 16.0 microg/ml, and therapeutic index (TI) value of 6.7.

Two new 6,7-seco-ent-kaurane diterpenoids, isojaponins A (1) and B (2), together with 18 known ent-kaurane diterpenoids were isolated from the aerial parts of Isodon japonicus. The structures of the two new compounds were elucidated by extensive 1D- and 2D-NMR spectroscopic methods in combination with MS experiments.

A pentacyclic ent-kauranoid, nervonin A ( 1), with an unprecedented cyclobutane moiety in the structure, and nine other new ent-kaurane diterpenoids, nervonins B-J ( 2- 10), along with 10 known ones ( 11- 20), were isolated from Isodon nervosus. Their structures were elucidated by detailed spectroscopic analysis. All diterpenoids were assayed for their cytotoxicity against K562, A549, and HepG2 human cell lines. Compounds 2, 11, 16, 17, and 20 showed significant cytotoxicity.

Two new dibenzocyclooctadiene lignans angeloyl-(+)-gomisin K-3 (1) and methylisogomisin O (2), together with six known ones, isogomisin O, angeloylisogomisin O, gomisin O, angeloygomisin O, benzoylgomisin O, epigomisin O, and four 1,4-bis(phenyl)-2,3-dimethylbutane type lignans, pregomisin, meso-dihydroguaiaretic acid, isoanwulignan, and sphenanlignan were isolated from the aerial parts of Schisandra propinyua var. propingua. The structures of 1 and 2 were elucidated by spectroscopic methods including extensive 1D- and 2D-NMR techniques.

A phytochemical study of secondary metabolites produced by Schisandra chinensis has led to the isolation of six novel highly oxygenated nortriterpenoids, wuweizidilactones A-F (1-6). Compounds 3-6 possess an unprecedented 3,4-seco-18(13-->14)-abeo-artane skeleton. Interestingly, structures 3-6 have a beta-oriented methyl group at the C-14 position. This structural feature corroborates the biogenetic pathway proposed for the formation of 18-norschiartane-type compounds 1 and 2. The structures of these novel metabolites were established on the basis of their detailed spectroscopic analysis. The structure of 1 was also confirmed by single-crystal X-ray diffraction analysis. For the first time, the absolute configuration of these nortriterpenoids was determined by using a modified Mosher method.

Pre-schisanartanin (1) and schindilactones A−C (2−4) were isolated from Schisandra chinensis. Among them, compound 1 had an unprecedented carbon skeleton. More importantly, the structure features of this compound provided new insight into the biosynthesis of triterpenoids with schisanartane skeleton. Their structures were determined by extensive spectroscopic analysis, single-crystal X-ray diffraction, and on the basis of the absolute structure of one related nortriterpenoid (5), which was determined for the first time by a modified Mosher method.