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Two new guaianolide sesquiterpenes, lanicepines A ( 1 ) and B ( 2 ), possessing unusual amino acid-derived substituents at C-13, were isolated from the flowering aerial parts of Saussurea laniceps , a traditional herbal medicine also known as "snow lotus". The structures of 1 and 2 were elucidated based on spectroscopic analysis including applications of the modified Mosher's method and Marfey's method as well as ECD calculations. Lanicepine A ( 1 ) contains a dihydropyridinone moiety with a carbamoyl and a hydroxymethyl group. This substituent was considered to consist of asparagine and a C 4 unit. In contrast, lanicepine B ( 2 ) has a substituent that seems to be derived from l-proline and a C 4 unit. Lanicepines A ( 1 ) and B ( 2 ) and two related known sesquiterpenes isolated from the same plant material, 11β,13-dihydrodesacylcynaropicrin ( 3 ) and 11β,13-dihydrodesacylcynaropicrin 8- O -β-d-glucoside ( 4 ), demonstrated inhibitory activity against IL-1β production from LPS-stimulated microglial cells.

An investigation of an endolichenic Beauveria sp. led to the discovery of seven new cyclotetradepsipeptides, beauveamides A-G ( 2 - 8 ), along with the known beauverolide Ka ( 1 ). All incorporate a 3-hydroxy-4-methyldecanoic acid (HMDA) moiety in their structures. Their configuration was determined through Marfey's, J -based configuration analysis, and NMR computational methods, representing the first time that the stereostructures of HMDA-moiety-containing cyclotetradepsipeptides have been established. Compounds 1 and 2 exhibited protecting effects on HEI-OC1 cells at 10 μM, while 1 , 4 , and 5 could stimulate glucose uptake in cultured rat L6 myoblasts at 50 μM. Compound 1 showed dose-dependent activity in both L6 myoblasts and myotubes.

Eight new diterpenoids ( 1 - 8 ) with varied structures were isolated from the aerial parts of Isodon xerophilus . Among them, xerophilsin A ( 1 ) was found to be an unusual meroditerpenoid representing a hybrid of an ent- kauranoid and a long-chain aliphatic ester, xerophilsins B-D ( 2 - 4 ) are dimeric ent -kauranoids, while xerophilsins E-H ( 5 - 8 ) are new ent- kauranoids. The structures of 1 - 8 were elucidated mainly through the analyses of their spectroscopic data. The absolute configurations of 2 , 6 , and 8 were confirmed by single-crystal X-ray diffraction, and the configuration of C-16 in 7 was established through quantum chemical calculation of NMR chemical shifts, as well as modeling of key interproton distances. Bioactivity evaluation of all isolated compounds revealed that 2 , 3 , and 5 inhibited NO production in LPS-stimulated RAW264.7 cells.

The enantiomers (+)- and (-)-alternarilactone A (1), the first examples of dibenzo-α-pyrones bearing a diepoxy-cage-like moiety, were isolated from the endophytic fungus Alternaria sp. hh930. The deficiency in 1 H- 1 H COSY and HMBC correlations caused by the highly oxidized caged system of 1 and the deceptive and ambiguous signals such as "W" couplings in NMR data increased the risk of structure misassignment of 1. By performing a quantum chemical calculation of the NMR chemical shifts together with a DP4+ probability analysis and single-crystal X-ray crystallographic experiment, their structures were unambiguously determined, and their absolute configurations were determined by ECD calculations.

A phytochemical investigation of an ethyl acetate extract of the aerial parts of Isodon pharicus led to the isolation of 21 new 7α,20-epoxy-ent-kaurane diterpenoids, pharicins C-W (1-21), and 29 known (22-50) analogues. The structural characterization of 1-21 and assignment of their relative configurations were accomplished by spectroscopic data interpretation, while the structures of 1 and 16 were confirmed by X-ray crystallography. The absolute stereostructure of 1 was confirmed by electronic circular dichroism data analysis. Twenty-five of the diterpenoids were screened for their cytotoxic activities against a panel of tumor cell lines, including HL-60, SMMC-7721, A-549, MCF-7, and SW-480. Compounds 11, 16, 38, and 48 exhibited inhibitory activities against these tumor cell lines with IC 50 values ranging from 1.01 to 9.62 μM, while 2, 15, 29, and 47 exhibited moderate cytotoxic potency.

Fourteen new diterpenoids (1-14) based on four skeletal types and two known analogues (15 and 16) were isolated from the aerial parts of Isodon scoparius. Compound 2 is the first ent-kaurane diterpenoid featuring a 1,11-ether bridge, and the structures of these new compounds were established mainly by NMR and MS methods. The absolute configurations of 1 and 5 and the relative configuration of 3 were determined using single-crystal X-ray diffraction. The absolute configuration of 14 was determined by comparison of the experimental and calculated electronic circular dichroism spectra. Compounds 1, 4, and 15 were active against five human tumor cell lines (HL-60, SMMC-7721, A-549, MCF-7, and SW-480), and they also inhibited NO production in LPS-stimulated RAW264.7 cells, with IC 50 values of 1.0, 3.1, and 1.8 μM, respectively.

Fourteen new rearranged 6/6/5/6-fused triterpenoid acids, namely, kadcoccine acids A-N (1-14), were isolated from an EtOAc-soluble extract of the stems of Kadsura coccinea. Their structures were characterized mainly by analyzing 1D and 2D NMR and HRESIMS data and were shown to feature a rare 14(13→12)-abeo-lanostane skeleton. Compounds 7 and 8 represented the first examples of a 5-substituted 2(5H)-furanone motif on the C-17 side chain of this skeleton. The absolute configurations of C-23 for compounds 1, 7, and 8 were determined by comparison of their experimental electronic circular dichroism spectra. All the isolates were screened for their in vitro cytotoxicity against six human tumor cell lines (HL-60, SMMC-7721, A-549, MCF-7, SW-480, and HeLa), and compounds 2 and 8 exhibited weak inhibitory effects with IC 50 values ranging from 3.11 to 7.77 μM.

Thirty-two enmein-type ent-kaurane diterpenoids, including 13 new compounds, were isolated from the aerial parts of Isodon phyllostachys. Compounds 1 and 2 are the first examples of 3,20:6,20-diepoxyenmein-type ent-kauranoids, and the structures of these new compounds were established mainly by analyzing NMR and HREIMS data. The absolute configurations of 1 and 8 and the relative configuration of 9 were determined using single-crystal X-ray diffraction. Compounds 11, 15, 20, and 21 were active against five human cancer cell lines (HL-60, SMMC-7721, A-549, MCF-7, and SW-480), with IC50 values ranging from 1.2 to 5.0 μM. Compounds 3, 11, 15, 17, 20, 21, 25, and 29 strongly inhibited NO production in LPS-stimulated RAW264.7 cells, with IC50 values ranging from 0.74 to 4.93 μM.

Penicilfuranone A (1), a novel furancarboxylic acid, and its proposed biosynthetic precursor, gregatin A (2), were isolated from the cultures of the fungus Penicillium sp. sh18 endophytic to the stems of Isodon eriocalyx var. laxiflora guided by HPLC-MS. X-ray crystallography was applied to the structure determination of furancarboxylic acid for the first time, allowing unambiguous assignment of 1. Penicilfuranone A displays a significant antifibrotic effect in activated hepatic stellate cells via negative regulation of transforming growth factor-β (TGF-β)/Smad signaling.

Eleven triterpene acids including 10 new compounds (kadcoccinic acids A-J, 1-10) were isolated from the stems of Kadsura coccinea. Except for 10, these compounds feature a rearranged lanostane skeleton with a 6/6/5/6 tetracyclic ring system, and compounds 1 and 2 are the first examples of 2,3-seco-6/6/5/6-fused tetracyclic triterpenoids. Their structures were established primarily by spectroscopic and spectrometric methods. Additionally, the absolute configuration of 3 was determined by single-crystal X-ray diffraction. Several of the compounds isolated were tested for their anti-HIV-1 and cytotoxic activities.

Two compounds belonging to a new group of diterpene alkaloids, kaurines A and B (1 and 2), and an alkaloid bearing a succinimide moiety (3) were obtained from Isodon rubescens. Their structures and absolute configurations were determined by spectroscopy and quantum-chemical computational (13)C NMR and ECD data analysis. These alkaloids differ from known diterpene alkaloids and diterpenoids and are presumably biosynthesized from ent-kaurane diterpenoids.

Thirteen new heterodimeric ent-kauranoids, bistenuifolins A-M (1-13), were isolated from the aerial parts of Isodon tenuifolius. The constituent units of compounds 1-6 were linked by a six-membered dihydropyran ring, while those of compounds 7-11 were joined by a rare single carbon-carbon bond (C-16→C-17'). The constituent units of 12 and 13 were linked via an unusual cyclobutane moiety. The structures of these metabolites were established via spectrometric analyses, and the absolute configurations of 1 and 4 were defined by single-crystal X-ray diffraction. Selected compounds were evaluated for their cytotoxicity against a small panel of human tumor cell lines; bistenuifolin B (2) exhibited weak inhibitory effects.

Phytochemical investigation of EtOAc extracts of the aerial parts of Isodon wikstroemioides afforded 18 new ent-kaurane diterpenoids (wikstroemioidins E-V, 1-18), along with 17 known analogues (19-35). The absolute configurations of 1 and 16 were confirmed by single-crystal X-ray diffraction analysis. The isolates were screened against five human tumor cell lines; compounds 3, 4, 9, 11-13, 23, 25-28, and 33 exhibited significant cytotoxic activity against all five, with IC50 values ranging from 0.4 to 5.1 μM. In addition, 17 of the isolates strongly inhibited nitric oxide production in LPS-activated RAW264.7 macrophages.

Three new triterpenoids, kadcotriones A-C (1-3), together with the biogenetically related lanostane-type triterpenoid (4), were isolated from Kadsura coccinea. Compound 1 features a 12,14β-dimethyl 6/6/6-fused tricyclic skeleton, while 2 and 3 are characterized by a 6/6/5-ring system. Their structures were determined by NMR and electronic circular dichroism spectroscopic methods. Compounds 2 and 4 exhibited anti-HIV-1 activities with EC50 values of 30.29 and 54.81 μM, respectively.

Fourteen enmein-type 6,7-seco-ent-kaurane diterpenoids, seven new ones (sculponins M-S, 1-7) and seven known compounds (8-14), were isolated from the aerial parts of Isodon sculponeatus . Compound 1 is the first example of an ent-kauranoid, possessing a 11,12-epoxy group, and compounds 6 and 7 have a rare 3,6-epoxy group. The structures were established primarily by NMR and MS methods, and the absolute configurations of 1, 3, and 6 were determined by single-crystal X-ray diffraction. Compound 14 showed significant cytotoxic activity against five human tumor lines, with IC50 values ranging from 1.0 to 3.5 μM, and it also inhibited NO production in LPS-stimulated RAW264.7 cells, with an IC50 value of 2.2 μM.

Isorosthin A (1), the first 20-nor-enmein-type diterpenoid, and 15 new ent-kauranoids, isorosthins B-P (2-16), along with 22 known analogues were isolated from the aerial parts of Isodon rosthornii. The structures of 1-16 were elucidated by means of spectroscopic analysis. The relative configuration of 2 and the absolute configuration of 3 were determined by single-crystal X-ray diffraction. Cytotoxicity evaluation against five human tumor lines showed inhibitory effects by several of the compounds tested. Furthermore, 12 of the isolates exhibited inhibitory activity against nitric oxide production in LPS-activated RAW264.7 macrophages.

Seven new unusual dibenzocyclooctadiene lignans, neglignans A-G (1-7), together with 16 known dibenzocyclooctadiene lignans, were isolated from the stems of Schisandra neglecta. Compounds 1 and 2 are the first dibenzocyclooctadiene lignans bearing a carboxyl group at C-4, and compounds 3 and 4 are the first 7,8-seco-dibenzocyclooctadiene lignans found from Nature. The new compounds (1-7) and several of the known compounds were evaluated for their anti-HIV activity and cytotoxicity. Compounds 2 and 6 showed anti-HIV-1 activities with therapeutic index values greater than 50, and compound 4 showed cytotoxicity against the NB4 and SHSY5Y cancer cell lines with IC50 values of 2.9 and 3.3 μM, respectively.

Seven new dibenzocyclooctadiene lignans, marlignans M-S (1-7), four new norlignans, marphenols C-F (8-11), and 21 known compounds (12-32) were isolated from the fruits of Schisandra wilsoniana. The structures of 1-11 were elucidated by spectroscopic methods including 1D- and 2D-NMR techniques and CD experiments. Compounds 1-11 were evaluated for their anti-HIV activities and showed EC(50) values in the range 2.97-6.18 μg/mL and therapeutic index values of 5.33-29.13.

Three new abietane diterpenoids, isoabietenins A-C (1-3), and 13 new ent-kauranoids, tenuifolins A-M (4-16), along with four known compounds (17-20), were isolated from the aerial parts of Isodon tenuifolius. The structures of the new metabolites were established on the basis of detailed spectroscopic analysis. The absolute configurations of 1, 15, and 16 were confirmed by single-crystal X-ray diffraction. Selected compounds were evaluated for their cytotoxicity against a small panel of human tumor cell lines, and some compounds showed inhibitory effects. Furthermore, several isolates exhibited inhibitory activity against nitric oxide production in LPS-activated RAW264.7 macrophages.

Laxiflorolides A (1) and B (2), two unprecedented epimeric bishomoditerpene lactones with a unique C(22) framework, along with laxiflorins P-R (3-5), maoecrystal P (6), maoecrystal C (7), and eriocalyxin B (8), were isolated from the leaves of I. eriocalyx var. laxiflora. The structures of 1 and 2, including the absolute configurations, were determined by spectroscopic methods and single-crystal X-ray diffraction analysis. All of the compounds isolated were evaluated for their cytotoxicity against five tumor cell lines. Compounds 3, 6, and 8 showed remarkable cytotoxic activity against certain cell lines compared with the positive control.

Eleven new dibenzocyclooctadiene lignans, polysperlignans A-K (1-11), and eight known analogues (12-19) were isolated from the stems of Kadsura polysperma. Their structures and absolute configurations were established using a combination of MS, NMR, CD, and single-crystal X-ray diffraction techniques. Selected compounds were evaluated for activity against β-amyloid- or hydrogen peroxide-induced neurotoxicity on PC12 cells, and 1, 2, 4, 5, 13, and 16 showed statistically significant neuroprotective effects in these in vitro assays.

Twelve new diterpenoids, isoadenolins A-L (1-12), and 24 known ones were isolated from the aerial parts of Isodon adenolomus. Their structures were identified using spectroscopic data, and the absolute configurations of 1 and 14 were determined by single-crystal X-ray diffraction. Selected compounds were evaluated for their in vitro cytotoxicity against human tumor HL-60, SMMC-7721, A-549, MCF-7, and SW-480 cell lines. Compounds 9, 13-16, and 21 showed significant inhibitory effects on all five cells, with IC50 values in the range 0.7-9.7 μM.

Fourteen new dibenzocyclooctadiene lignans, ananolignans A-N (1-14), together with five known compounds, were isolated from the seeds of Kadsura ananosma. The structures and absolute configurations of 1-14 were established using a combination of spectroscopic methods including 1D- and 2D-NMR and CD techniques. The biological activity of the isolated lignans was evaluated, and ananolignan F (6) and ananolignan L (12) showed significant neuroprotective effects in an in vitro assay.

A new ent-atisanoid, eriocatisin A (1), six new ent-abietanoids, eriocasins B-E (2-4, 7), 3-acetyleriocasin C (5), and 3β-acetoxyeriocasin D (6), and seven new ent-kauranoids, maoesins A-F (8, 10-14) and 3α-acetoxy-maoesin A (9), together with 21 known compounds, were isolated from the aerial parts of Isodon eriocalyx. The structures of 1-14 were determined by spectroscopic data interpretation. All compounds isolated were evaluated for their in vitro growth inhibitory activity against the HT-29, BEL-7402, and SK-OV-3 human cancer cell lines. Compounds 17, 18, and 20 showed inhibitory effects for all three tumor cell lines used, with IC(50) values in the range 2.1-7.3 μM.

Twenty-one highly oxygenated nortriterpenoids with a schisanartane skeleton were isolated from the stems of Schisandra propinqua var. propinqua. These nortriterpenoids featured a polycyclic framework composed of 7/8/5 consecutive carbocycles, which were organized by similar 5/5/7/5/7/5 rings A-F and varied oxygen-containing rings G and H. A biosynthetic classification of these compounds is proposed on the basis of their diverse post-modifications.

An ethanolic extract of Antiaris toxicaria trunk bark showed potent in vitro cardiotonic effect on isolated guinea pig atria. Bioassay-guided fractionation of the extract led to identification of nine new cardiac glycosides (1-9, named antiarosides A-I), antiarotoxinin A (10), and 18 known compounds. Their structures were established using MS and NMR spectroscopic studies, including homonuclear and heteronuclear correlation experiments. The ability of these cardiotonic compounds to produce positive inotropic action and their safety indexes were examined in comparison with those of ouabain, a classical inhibitor of Na(+)/K(+)-ATPase. Malayoside (23) was nearly equipotent and had a similar safety index to ouabain in guinea pig atria. However, the maximal positive inotropic effect and safety index of 23 in papillary muscle were better than those of ouabain. An electrophysiological recording showed that 23 inhibited the sodium pump current in a concentration-dependent manner.

Ten new ent-kaurane diterpenoids, isolushinins A-J (1-10), together with 20 known compounds, were isolated from the aerial parts of Isodon rubescens var. lushiensis. The structures of 1-10 were elucidated by spectroscopic analysis. Several of the compounds isolated were evaluated for their cytotoxicity against the HL-60, SMMC-7721, A-549, SK-BR-3, and PANC-1 human cancer cell lines, and some exhibited quite potent inhibitory activities.

Twelve new dibenzocyclooctadiene lignans, marlignans A-L (1-12), together with 16 known compounds, were isolated from the leaves and stems of Schisandra wilsoniana. The structures of 1-12 were elucidated by spectroscopic methods including 1D- and 2D-NMR techniques. Compounds 1-12 were evaluated for their anti-HIV activities, of which compounds 3, 6, 8, and 12 showed modest activities with therapeutic index values of 13.2, 15.6, 17.6, and 16.4, respectively.

Six new nortriterpenoids, schirubridilactones A-F (1-6), as well as 14 known compounds, were isolated from the leaves and stems of Schisandra rubriflora. The structures of 1-6 were elucidated on the basis of spectroscopic methods including HSQC, HMBC, (1)H-(1)H COSY, and ROESY NMR experiments. The relative stereochemistry of 1 was confirmed through single-crystal X-ray analysis. In addition, compounds 1-6 showed anti-HIV-1 activity with EC(50) values in the range 14.3-80.8 microg/mL and selectivity indices in the range 2.2-9.0.

Six new triterpene dilactones with a rare rearranged pentacyclic skeleton, longipedlactones K-P (1-6), and seven known analogues (7-13) were isolated from the stems of Kadsura ananosma. Compound 1 was found to possess a unique peroxide bridge between C-1 and C-9 in rings A and B. The structures of these new compounds were established on the basis of spectroscopic data analysis, especially of their 2D NMR spectra. In the evaluation of the in vitro cytotoxicity of these compounds against a small panel of human cancer cell lines, compounds 3, 7, 9, and 13 were found to be the most potent against HL-60 acute leukemia cell.

Nine new ent-kauranoids, sculponins D-L (1-9), and 14 known diterpenoids (10-23) were isolated from the aerial parts of Isodon sculponeatus. The structures of the new diterpenoids were determined by detailed interpretation of their 1D and 2D NMR spectra and HRESIMS. The isolated compounds were evaluated for their cytotoxic activities against a small panel of human cancer cell lines.

Three new nortriterpenoids, schigrandilactones A-C (1-3), along with eight known compounds, were isolated from an organic solvent extract of Schisandra grandiflora. Compounds 1 and 2 feature a spirocyclic moiety in their structures, and compound 3 was characterized with a new oxygenated pattern. The relative configurations of 1 and 3 were determined through single-crystal X-ray experiments. In addition, compounds 1 and 2 displayed cytotoxic activity against two human cancer cell lines, and compound 3 showed anti-HIV-1 inhibition in infected C8166 cells.

Xerophilusin A (1), xerophilusin B (2), longikaurin B (3), and xerophilusin F (4) from Isodon xerophylus inhibit LPS-induced NO production in RAW 264.7 macrophages, with IC(50) values of 0.60, 0.23, 0.44, and 0.67 muM, respectively, and they all inhibited mRNA production in these same cells. They decreased the luciferase activity in RAW 264.7 cells transiently transfected with the NF-kappaB-dependent luciferase reporter, with IC(50) values of 1.8, 0.7, 1.2, and 1.6 muM, respectively. Compounds 1-3 reduced NF-kappaB activation, with compound 4 showing no effect, but p65 translocation from the cytoplasm to the nucleus and the LPS-induced degradation of IkappaB were inhibited by all four test compounds. These findings indicate that ent-kauranes are potential anti-inflammatory agents, with a specific mechanism in which both the inhibition of NF-kappaB translocation and the consequent decrease of pro-inflammatory mediators are implicated.

Fourteen new lignans, tiegusanins A-N (1-14), together with 13 known compounds were isolated from the aerial parts of Schisandra propinqua var. sinensis. The structures and absolute configurations of 1-13 were established using a combination of spectroscopic techniques. Compound 14 was obtained as a racemate. When evaluated for inhibitory activity against HIV-1, tiegusanin G (7) showed anti-HIV-1 activity with an EC(50) value of 7.9 microM and a therapeutic index (TI) of more than 25.

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.

Nine new ent-kaurane diterpenoids, isoscoparins D-L (1-9), and an artificial product, the acetonide of rabdoloxin A (10), along with 16 known analogues (11-26), were isolated from the leaves of Isodon scoparius. The new structures were determined by 1D and 2D NMR spectroscopic analysis. Selected compounds were evaluated for their cytotoxicity against NB4, A549, PC-3, MCF-7, and SH-SY5Y cell lines.

Ten new highly oxygenated triterpenoids, kadcoccilactones A-J (1-10), and two known triterpenoids, kadsuphilactone A and micrandilactone B, were isolated from the stems of the evergreen climbing plant Kadsura coccinea. The structures of the new compounds were elucidated by spectroscopic evidence, with that of 1 confirmed by single-crystal X-ray diffraction analysis. This is the first report on nortriterpenoids (2, 4-6, 8-10) from the genus Kadsura.

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.

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.

Phytochemical investigation of Kadsura angustifolia led to the isolation and identification of 26 lignans and two triterpenoids, including 11 new lignans named kadangustins A-K ( 1- 11). The structures and stereochemistry of 1- 11 were elucidated by analysis of spectroscopic data. Except for 11 and 20, all the lignans were evaluated for their inhibitory activity against HIV-1. Binankadsurin A ( 19) showed anti-HIV activity with an EC 50 value of 3.86 microM.

Four new triterpenoids, kadlongilactones C-F (2-5), containing a consecutive hexacyclic [7,7,5,6,6,6] ring system, were isolated from the leaves and stems of Kadsura longipedunculata. In comparison with the NMR data of kadlongilactones A (1) and D (3), a significant phenomena was discovered that ring D of 3 inverted from a half-chair in 1 to a half-boat conformation when the HO-16 group changed from alpha- to beta-orientation. The structures of 2-5 were established on the basis of detailed spectroscopic analysis, and DFT computational methods were applied in the structural validation of compounds 3 and 5. Compounds 1-4 showed significant cytotoxicity against A549, HT-29, and K562 cell lines with IC50 values of 0.49-3.61 microM in vitro.

Bioassay-directed fractionation of the leaves of the medicinal plant Isodon xerophilus led to the isolation of a series of potential antitumor molecules. Thirteen new (1-13) and 23 (14-36) known diterpenoids were isolated and identified, representing ent-kauranoids of several structural types. The structures of 1-13 were determined by means of spectroscopic studies. The absolute configurations of the new compounds were clarified by CD spectroscopic studies or were postulated on biogenetic grounds. All compounds obtained were evaluated for their cytotoxic activity against the K562, MKN45, and HepG2 cell lines. Compounds 1, 2, 11, 16-19, 23, 26-28, 30, and 32 demonstrated significant cytotoxic activity for one or more cell lines.

Investigation of an organic extract of Schisandra rubriflora led to the isolation of three new highly oxygenated nortriterpenoids, named rubriflorins A-C (1-3), together with six related known compounds (4-9). Their structures were elucidated by spectroscopic evidence. Compounds 1-3 feature the opening of ring A compared with related known nortriterpenoids isolated from the genus Schisandra and showed anti-HIV-1 activities with EC50 values of 10.0, 16.2, and 81.3 microg/mL, respectively.

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.

Three new prenylated phenolic compounds, fornicins A-C (1-3), were obtained from the fruiting bodies of Ganoderma fornicatum. The structure elucidation was achieved by interpretation of spectroscopic data. These compounds exhibited moderate cytotoxic activity with IC(50) values of 15 to 30 microg/mL in Hep-2 cells.

Nine new 7alpha,20-epoxy-ent-kaurane diterpenoids, parvifolines C-K (1-9), together with 12 known analogues, rabdoternin G (10), adenolin E (11), lasiodonin (12), lushanrubescensin F (13), parvifoliside (14), effusanin A (15), effusanin B (16), effusanin E (17), taibaihenryiin A (18), shikokianin (19), maoyecrystal J (20), and the acetonide of lasiodonin (21), were isolated from the leaves of Isodon parvifolius. The structures of compounds 1-9 were determined on the basis of spectroscopic methods including extensive 1D and 2D NMR analysis. The new diterpenoids (1-9) and lasiodonin (12) were evaluated for their inhibitory activity against A549, HT-29, and K562 cell lines.

Six new nortriterpenoids, lancifodilactones I-N (1-6), as well as nine known ones, were isolated from the leaves and stems of Schisandra lancifolia. Their structures were elucidated on the basis of spectroscopic methods including 2D NMR analysis, and the structures of compounds 1 and 4 were further confirmed by single-crystal X-ray crystallography. In addition, all new compounds were tested for anti-HIV-1 activity.

Six new ent-labdane diterpenoids, 3-O-beta-D-glucopyranosyl-14,19-dideoxyandrographolide (1), 14-deoxy-17-hydroxyandrographolide (2), 19-O-[beta-D-apiofuranosyl(1-->2)-beta-D-glucopyranoyl]-3,14-dideoxyandrographolide (3), 3-O-beta-d-glucopyranosylandrographolide (4), 12S-hydroxyandrographolide (5), and andrographatoside (6), together with 17 known analogues, were isolated from the aerial parts of Andrographis paniculata. The structures of 1-6 were determined by spectroscopic data analysis. All compounds isolated were evaluated for their inhibitory activity against several bacterial and fungal strains.

A new trinorcycloartane triterpenoid, lancifodilactone H (1), and a new A ring-secocycloartane triterpenoid, lancifoic acid A (2), together with a known compound, nigranoic acid (3), were isolated from the leaves and stems of Schisandra lancifolia. Their structures were elucidated by spectroscopic data analysis. Compound 1 features a biosynthetically modified seven-membered lactone ring, which was confirmed by single-crystal X-ray diffraction. Compounds 1-3 exhibited weak anti-HIV-1 activity in vitro.