Search

Three new isopimaric acid diterpenoids, 6-oxoisopimaric acid (1), 6α-hydroxyisopimaric acid (2), and isopimara-7,9(11),15-trien-18-oic acid (4), together with two known isopimaric acid diterpenoids, isopimaric acid (3), and 8(14),15-isopimaradien-18-oic acid (5), were isolated from the bark of Cryptomeria japonica D. Don. Their structures were determined by analysis of spectroscopic data and comparison with the spectral data of known analogues. At the concentration of 50 μM, compounds 1–5 inhibited xanthine oxidase activity by 17.3, 16.5, 2.6, 30.5, and 24.5 %, respectively.

Two new dimeric abietane-type diterpenoids, 12-hydroxyabieta-8,11,13-trien-7-α-yl 7-oxoabieta-8,11,13-trien-12-yl peroxide (trivial name japonicinol C, 1) and 12-hydroxyabieta-8,11,13-trien-7-α-yl 7-oxoabieta-5,8,11,13-tetraen-12-yl peroxide (trivial name japonicinol D, 3), together with two known dimeric abietane-type diterpenoids, obtusanol A (2) and 7-α-(2-butoxyethoxy)-12-hydroxyabieta-6-yl 6,7-dehydroabieta-8,11,13-trien-12-yl ether (4), were isolated from the methanol extract of the bark of Cryptomeria japonica. Their structures were established by mean of spectroscopic analysis and comparison of NMR data with those of known analogues. At a concentration of 50 μM, compounds 1–4 inhibited xanthine oxidase activity by 29.8, 39.3, 27.1, and 14.7 %, respectively. In addition, compounds 1 and 4 also showed 13.9 and 20.5 % inhibition toward angiotensin-converting enzyme (ACE), respectively.

A cucurbitane triterpenoid, 7β-butoxy-3β-hydroxy-25-methoxycucurbita-5,23(E)-dien-19-al (1), was isolated from the fruit pulp of Momordica charantia. Structure determination of the new compound was accomplished by spectroscopic analyses including 1D and 2D NMR (1H, 13C, COSY, HMQC, HMBC, and NOESY) and EI-MS and comparison with the data of known analogues.

In the continuous search for α-glucosidase inhibitors, eleven phenolic compounds (1-11) were isolated from the root bark of Paeonia suffruticosa. Their α-glucosidase inhibitory activity and inhibition mechanism were investigated using an in vitro inhibition assay and molecular docking studies. Compounds 2, 5, 6, and 8-11 (IC50 between 290 and 431 µM) inhibited α-glucosidase more effectively than the reference compound acarbose (IC50=1463 ± 29.5 µM). Among them, compound 10 exhibited the highest α-glucosidase inhibitory effect with an IC50 value of 290.4 ± 9.6 µM. Compounds 2, 5, 9 10 and 11 were found to be competitive inhibitors, while compounds 6 and 8 were noncompetitive inhibitors of α-glucosidase. Computational analyses showed that the main binding forces between the compounds and the main residues were hydrogen bonds. The results indicated that these compounds had considerable α-glucosidase inhibitory activity.

(+)-Bornyl p-coumarate is an active substance that is abundant in the Piper betle stem and has been shown to possess bioactivity against bacteria and a strong antioxidative effect. In the current study, we examined the actions of (+)-bornyl p-coumarate against A2058 and A375 melanoma cells. The inhibition effects of (+)-bornyl p-coumarate on these cell lines were assessed by 3-(4,5-Dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay and the underlying mechanisms were identified by immunostaining, flow cytometry and western blotting of proteins associated with apoptosis and autophagy. Our results demonstrated that (+)-bornyl p-coumarate inhibited melanoma cell proliferation and caused loss of mitochondrial membrane potential, demonstrating treatment induced apoptosis. In addition, western blotting revealed that the process is mediated by caspase-dependent pathways, release of cytochrome C, activation of pro-apoptotic proteins (Bax, Bad and caspase-3/-9) and suppression of anti-apoptotic proteins (Bcl-2, Bcl-xl and Mcl-1). Also, the upregulated expressions of p-PERK, p-eIF2&alpha, ATF4 and CCAAT/enhancer-binding protein (C/EBP)-homologous protein (CHOP) after treatment indicated that (+)-bornyl p-coumarate caused apoptosis via endoplasmic reticulum (ER) stress. Moreover, increased expressions of beclin-1, Atg3, Atg5, p62, LC3-I and LC3-II proteins and suppression by autophagic inhibitor 3-methyladenine (3-MA), indicated that (+)-bornyl p-coumarate triggered autophagy in the melanoma cells. In conclusion, our findings demonstrated that (+)-bornyl p-coumarate suppressed human melanoma cell growth and should be further investigated with regards to its potential use as a chemotherapy drug for the treatment of human melanoma.

Phytoantioxidants from Terminalia boivinii Tul. are of medical interest given their potential inhibitory capacity against the formation of glycation end products and key enzymes associated with metabolic syndrome. The present study investigated and compared the polyphenolic content and biological properties of ethyl acetate, n-butanol and aqueous solvent fractions of T. boivinii fruits, leaves, stem and bark methanolic extracts. The total bioactive content of the tested materials was evaluated by spectrophotometric methods. The antioxidant activity was analyzed using DPPH, superoxide anion radical, metal chelation and FRAP assays. The enzyme inhibitory properties were tested on α-glucosidase, α-amylase, lipase and HMG-CoA reductase enzymes, while antiglycation activities were evaluated by the bovine serum albumin (BSA) - methylglyoxal (MG) method. Phytochemical analysis indicated that the ethyl acetate fractions had high levels of phenols (40.58 ± 2.94 mg GAE/g DW of leaves) and flavonoids (20.32 ± 1.62 mg QE/g DW of leaves) compared to the other extracts, which is directly related with their significant antiradical, reducing power, α-glucosidase, lipase and HMG-CoA reductase inhibitory ability. However, the water fraction with the lowest polyphenol content was more active in metal chelation. Moreover, the antiglycation activities followed a similar pattern to the radical scavenging activities. Our results showed that T. boivinii is a viable source of natural bioactive antioxidant and enzyme-inhibiting chemicals that maybe considered for commercial exploitation.

Three new dimeric abietane-type diterpenoids, abieta-6,8,11,13-tetraen-12-yl 12-hydroxyabieta-8,11,13-trien-7&alpha, yl peroxide (1), abieta-6,8,11,13-tetraen-12-yl 12-hydroxyabieta-8,11,13-trien-7&beta, yl peroxide (2), and 12-hydroxyabieta-8,11,13-trien-7&beta, yl 7-oxoabieta-5,8,11,13-tetraen-12-yl peroxide (3), together with four known abietane-type diterpenoids (4&ndash, 7) were isolated from the methanol extract of the bark of Cryptomeria japonica. Their structures were elucidated on the basis of spectroscopic analysis and comparison of NMR data with those of known analogues. At a concentration of 50 &mu, M, compounds 1, 2, and 3 showed 26.2%, 23.6%, and 35.7% inhibition towards xanthine oxidase enzyme, respectively. In addition, compound 3 also showed 24.9% inhibition toward angiotensin-converting enzyme (ACE).

In this study, hot-water extracts (HW) from roots of Vitis thunbergii var. taiwaniana (VTT-R) were shown to lower levels of lipid accumulation significantly (P < 0.01 or 0.001) compared to the control in 3T3-L1 adipocytes. The VTT-R-HW (40 mg/kg) interventions concurrent with a high-fat (HF) diet in C57BL/6 mice over a 5 eek period were shown to reduce body weights significantly (P < 0.05) compared to those of mice fed a HF diet under the same food-intake regimen. The (+)-e-viniferin isolated from VTT-R-HW was shown to reduce the size of lipid deposits significantly compared to the control (P < 0.05 or 0.001) in 3T3-L1 adipocytes, and dose-dependent 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitions showed that the 50% inhibitory concentration was calculated to be 96 μM. The two-stage (+)-e-viniferin interventions (10 mg/kg, day 1 to day 38; 25 mg/kg, day 39 to day 58) were shown to lower mice body weights significantly (P < 0.05 or 0.001), the weight ratio of mesenteric fat, blood glucose, total cholesterol, and low-density lipoprotein compared to that of the HF group under the same food-intake regimen but without concurrent VTT-R-HW interventions. It might be possible to use VTT-R-HW or (+)-e-viniferin as an ingredient in the development of functional foods for weight management, and this will need to be investigated further.

An accurate and rapid liquid chromatography–electrospray ionizaion– tandem mass spectrometry (LC—ESI—MS/MS) analytical method was developed and validated for the simultaneous determination of antcins A, B, C, H, and K, dehydroeburicoic acid, and 4,7-dimethoxy-5-methyl-1,3-benzodioxole in the extract and capsule of Antrodia cinnamomea (AC) fruiting body. These seven signature compounds were ionized using an electrospray ion source and analyzed by a triple-quadrupole mass analyzer under a multiple reaction monitoring (MRM) mode. The MRM transitions of m/z 453/409 (antcin A), m/z 467/408 (antcin B), m/z 469/425 (antcin C), m/z 485/413 (antcin H), m/z 487/407 (antcin K), m/z 467/337 (dehydroeburicoic acid), and m/z 197/139 (4,7-dimethoxy-5-methyl-1,3-benzodioxole) were used to quantify these seven components, respectively. Their calibration curves presented good linear regressions (R2 > 0.997) within the tested concentration range. The intra- and inter-day precisions were less than 1.97% and 2.53%, respective...

In this study, we screened 10 resveratrol derivatives isolated from Ampelopsis brevipedunculata var. hancei (Planch.) Rehder (ABH) for angiotensin I converting enzyme (ACE) inhibitory (ACEI) activity. Among these compounds, (+)-hopeaphenol and (+)-vitisin A showed the lowest IC 50 values (∼1.5 μM) toward ACE. In addition, the compounds’ abundances and distributions in ABH were profiled using liquid chromatography–tandem mass spectrometry (LC–MS/MS). Interestingly, trimers and tetramers of resveratrol were mainly obtained from the bark of ABH when 90% ethanol was used for extraction. This result implies that the antihypertension effect of ABH extract may be mainly contributed by (+)-hopeaphenol ( F1 ) and (+)-vitisin A ( F2 ) in the ABH bark due to their remarkable ACE inhibitions. Moreover, the sizes and structures of these compounds were further correlated to their affinities toward ACE using molecular docking calculations. The results showed that resveratrol tetramers interact with ACE more favorably than other smaller oligomers.

Two new cucurbitane-type triterpenes, 25-methoxycucurbita-5,23(E)-diene-3β,19-diol (1) and 7β-ethoxy-3β-hydroxy-25-methoxycucurbita-5,23(E)-dien-19-al (2), together with three known cucurbitane-type triterpenes, 3β,7β,25-trihydroxycucurbita-5,23(E)-dien-19-al (3), (23E)-3β-hydroxy-7β,25-dimethoxycucurbita-5,23-dien-19-al (4), and 3β-hydroxy-25-methoxycucurbita-6,23(E)-dien-19,5β-olide (5), were isolated from the fruit pulp of Momordica charantia. The structures of two new compounds were elucidated on the basis of 1D and 2D NMR, MS, IR, optical rotation. Among these isolates, compounds 1, 2, and 5 showed slight cytotoxic activity against the SK-Hep 1 cell line with IC50 values of 33.1, 24.3, and 38.7 μM, respectively.

A new sterol, 5α,6α-epoxy-3β-hydroxy-(22E,24R)-ergosta-8,22-dien-7-one (1), together with eight known sterols, 5α,6α-epoxy-(22E,24R)-ergosta-8,22-diene-3β,7α-diol (2), 5α,6α-epoxy-(22E,24R)-ergosta-8,22-diene-3β,7β-diol (3), 5α,6α-epoxy-(22E,24R)-ergosta-8(14),22-diene-3β,7α-diol (4), 3β-hydroxy-(22E,24R)-ergosta-5,8,22-trien-7-one (5), ergosterol peroxide (6), clerosterol (7), decortinol (8), and decortinone (9), were isolated from the stems of Momordica charantia. Their structures were elucidated by mean of extensive spectroscopic methods, including 1H, 13C, 2D-NMR and HR-EI-MS, as well as comparison with the literature data. Compounds 1, 4, 5, 8, and 91 were not cytotoxic against the SK-Hep 1 cell line.

Two new cucurbitane triterpenes, (23E)-7β-methoxycucurbita-5,23,25-trien-3β-ol (1) and 23,25-dihydroxy-5β,19-epoxycucurbit-6-ene-3,24-dione (2), and a new D : C-friedooleanane triterpene, 3α-[(E)-feruloyloxy]-D : C-friedooleana-7,9(11)-dien-29-oic acid (3), together with two known D : C-friedooleanane triterpenes, 3β-[(E)-feruloyloxy]-D : C-friedooleana-7,9(11)-dien-29-oic acid (4) and 3-oxo-D : C-friedooleana-7,9(11)-dien-29-oic acid (5), were isolated from the stems of Momordica charantia. The structures of the new compounds 1–3 were determined by spectroscopic methods.

Four novel octanorcucurbitane triterpenes, octanorcucurbitacins A-D (1-4), together with one known octanorcucurbitane triterpene, kuguacin M (5), were isolated from the methyl alcohol extract of the stems of Momordica charantia. Their structures were elucidated on the basis of extensive spectroscopic analyses. Compound 3 inhibited tert-butyl hydroperoxide (t-BHP)-induced hepatotoxicity against HepG2 cells.

Stenotrophomonas maltophilia (Sm), with most of the isolates being resistant to multidrugs, is an opportunistic bacterium causing nosocomial infections. In this study, a novel virulent Sm phage, Smp14, was characterized. Electron microscopy showed that Smp14 resembled members of Myoviridae and adsorbed to poles of the host cells during infection. It lysed 37 of 87 clinical Sm isolates in spot test, displayed a latent period of ca. 20 min, and had a burst size of ca. 150. Its genome (estimated to be 160 kb by PFGE), containing m4C and two unknown modified bases other than m5C and m6A as identified by HPLC, resisted to digestion with many restriction endonucleases except MseI. These properties indicate that it is a novel Sm phage distinct from the previously reported phiSMA5 which has a genome of 250 kb digestible with various restriction enzymes. Sequencing of a 16 kb region revealed 12 ORFs encoding structural proteins sharing 15-45% identities with the homologues from T4-type phages. SDS-PAGE displayed 20 virion proteins, with the most abundant one being the 39 kDa major capsid protein (gp23), which had the N-terminal 52 amino acids removed. Phylogenetic analysis based on gp23 classified Smp14 into a novel single-membered T4-type subgroup.

A new tocopherol derivative, 7a-methoxy-a-tocopherol (1), and a new taraxastane triterpene, taraxast-1,20(30)-dien-3-one (5), together with four known compounds, β-tocopherol (2), α-tocopherol (3), α-tocospiro B (4) and taraxasterone (6) were isolated from the whole plant of Sida acuta. Their structures were elucidated by spectral analysis including MS, 1D and 2D-NMR spectroscopy. Among those compounds, compounds 1, 2, and 3 showed significant antioxidant effect (EC 50 = 86.9, 68.2, and 70.9 μM, respectively) in the DPPH radicals scavenging activity assay.

Five new cucurbitane-type triterpenes, (23E)-25-methoxycucurbit-23-ene-3beta,7beta-diol (1), (23E)-cucurbita-5,23,25-triene-3beta,7beta-diol (2), (23E)-25-hydroxycucurbita-5,23-diene-3,7-dione (3), (23E)-cucurbita-5,23,25-triene-3,7-dione (4), and (23E)-5beta,19-epoxycucurbita-6,23-diene-3beta,25-diol (5), together with one known triterpene, (23E)-5beta,19-epoxy-25-methoxycucurbita-6,23-dien-3beta-ol (6), have been isolated from the methanol extract of the stems of Momordica charantia. The structures of the new compounds were elucidated by spectroscopic methods.

Stenotrophomonas maltophilia is one of the most prevalent opportunistic bacteria causing nosocomial infections. It has become problematic because most of the isolates are resistant to multiple antibiotics, and therefore, development of phage therapy has attracted strong attention. In this study, eight S. maltophilia phages were isolated from clinical samples including patient specimens, catheter-related devices, and wastewater. These phages can be divided into four distinct groups based on host range and digestibility of the phage DNAs with different restriction endonucleases. One of them, designated φSMA5, was further characterized. Electron microscopy showed it resembled Myoviridae , with an isometric head (90 nm in diameter), a tail (90 nm long), a baseplate (25 nm wide), and short tail fibers. The φSMA5 double-stranded DNA, refractory to digestion by most restriction enzymes, was tested and estimated to be 250 kb by pulsed-field gel electrophoresis. This genome size is second to that of the largest phage, φKZ of Pseudomonas aeruginosa . In sodium dodecyl sulfate-polyacrylamide gel electrophoresis, 25 virion proteins were visualized. N-terminal sequencing of four of them suggested that each of them might have had its N terminus cleaved off. Among the 87 S. maltophilia strains collected in this study, only 61 were susceptible to φSMA5, indicating that more phages are needed toward a phage therapy strategy. Since literature search yielded no information about S. maltophilia phages, φSMA5 appears to be the first reported.

Eight compounds were purified from Mormodica charanti, and their chemical structures were determined in this study. Their anti-HBV and anti-inflammation activities were investigated. Compound EMCDO exhibited the most efficient effect in terms of reducing HBV surface antigen, e antigen and viral DNA levels in HBV particles or surface antigen-producing cells 2.2.15 and PLC/PRF/5, respectively. Tumor suppressor p53 played a significant role in EMCDO-mediated anti-HBV effects. Pretreatment with EMCDO prevented 2.2.15 cells-induced tumor formation in a nude mice subcutaneous model. The anti-HBV and anti-tumor activities of EMCDO were better than those of oltipraz, an inhibitor of HBV transcription. EMCDO reduced the proinflammatory cytokines and mediators in LPS-treated RAW264.7 cells in a dose-dependent manner. The LPS-upregulated phosphorylation level of Ika was reduced in the presence of EMCDO. The transcription activity of NF-kB was increased in cells treated with EMCDO. Utilization of a mouse ear edema model further confirmed the activity of EMCDO against TPA-elicited inflammation.

Two new 27-norcucurbitane triterpenoids, 5β,19-epoxy-3β-hydroxy-19( S)-methoxy-27-norcucurbita-6,23( E)-dien-25-one (1) and 3β-hydroxy-25-oxo-27-norcucurbita-6,23( E)-dien-5β,19-olide (2), together with one known cucurbitane triterpene, 5β,19-epoxycucurbita-6,23( E)-diene-3β,25-diol (3), were isolated from the fruits of Momordica charantia var. abbreviata. Their structures were elucidated by spectroscopic methods including EI-MS, 1H, 13C, and 2D NMR data and comparison with the data of known analogues.

Two new cucurbitane-type triterpenoids, 7β,23( S)-dimethoxycucurbita-5,24-dien-3β-ol (1) and 3 β-hydroxycucurbita-6,23( E),25-trien-5 β,19-olide (2), and two known cucurbitane-type triterpenoids, 7 β,25-dimethoxycucurbita-5,23( E)-dien-3 β-ol (3) and karavilagenin D (4), were isolated from the fruit pulp of Momordica charantia. Their structures were established by means of 1D and 2D NMR spectra (1H, 13C, COSY, HMQC, HMBC, and NOESY) as well as EI-MS data.

Two major acylated flavonoid tetraglycosides were isolated from the methanol extract of oolong tea. Their structures were elucidated by spectroscopic methods as quercetin 3-O-[2(G)-(E)-coumaroyl-3(G)-O-beta-D-glucosyl-3(R)-O-beta-D-glucosylrutinoside] (1) and kaempferol 3-O-[2(G)-(E)-coumaroyl-3(G)-O-beta-D-glucosyl-3(R)-O-beta-D-glucosylrutinoside] (2). Compounds 1 and 2 exhibited scavenging activity against DPPH radical with EC(50) values of 30.5 and 487.2 microM, respectively.

Protein N-terminal acetylation is one of the most common modifications occurring co- and post-translationally on either eukaryote or prokaryote proteins. However, compared to other protein modifications, the physiological role of protein N-terminal acetylation is relatively unclear. To explore the biological functions of protein N-terminal acetylation, a robust and large-scale method for qualitative and quantitative analysis of this modification is required. Enrichment of N(α)-acetylated peptides or depletion of the free N-terminal and internal tryptic peptides prior to analysis by mass spectrometry are necessary based on current technologies. This study demonstrated a simple strong cation exchange (SCX) fractionation method to selectively enrich N(α)-acetylated tryptic peptides via dimethyl labeling without the need for tedious protective labeling and depleting procedures. This method was introduced for the comprehensive analysis of N-terminal acetylated proteins from HepG2 cells. Several hundred N-terminal acetylation sites were readily identified in a single SCX flow-through fraction. Moreover, the N(α)-acetylated peptides of some protein isoforms were simultaneously observed in the SCX flow-through fraction, which indicated that this approach can be utilized to discriminate protein isoforms with very similar full sequences but different N-terminal sequences, such as β-actin/γ-actin, ERK1/ERK2, α-centractin/β-centractin, and ADP/ATP translocase 2 and 3. Compared to other methods, this method is relatively simple and can be directly implemented in a two-dimensional separation (SCX-RP)-mass spectrometry scheme for quantitative N-terminal proteomics using stable-isotope dimethyl labeling.

Three new cucurbitane-type triterpenoids, 5β,19-epoxy-23(R)-methoxycucurbita-6,24-dien-3β-ol (1), 5β,19-epoxy-23(S)-methoxycucurbita-6,24-dien-3β-ol (2), and 3β-hydroxy-23(R)-methoxycucurbita-6,24-dien-5β,19-olide (3), were isolated from the fruit pulp of Momordica charantia. Their structures were established on the basis of extensive NMR (1H, 13C, COSY, HMQC, HMBC, and NOESY) and EI-MS studies. Compound 1 exhibited cytotoxic activity against the SK-Hep 1 cell line.

Four new lactone chlorins, ficuschlorins A - D (1-4, resp.), and six known pheophytins were isolated from the leaves of Ficus microcarpa. The structures of these compounds were determined by 1D- and 2D-NMR spectroscopy, and other techniques. New natural pheophytins were rarely obtained. In the past ten years, only three new pheophytins were isolated from natural sources.

Three new triterpenoids (I)-(III) are isolated from the tendril climber Momordica charantia.

Two new methoxy lactone chlorins ficusmicrochlorin A (1) and ficusmicrochlorin B (2), and one new anhydride chlorin ficusmicrochlorin C (3), along with eight known pheophytins were isolated from the leaves of Ficus microcarpa. Their structures were determined by the extensive 1D- and 2D-NMR techniques. New pheophytin compound was rarely obtained from natural sources. In the past ten years, only three new natural pheophytins were characterized.

Two novel pentanorcucurbitane triterpenes, 22-hydroxy-23,24,25,26,27-pentanorcucurbit-5-en-3-one (1) and 3,7-dioxo-23,24,25,26,27-pentanorcucurbit-5-en-22-oic acid (2) together with a new trinorcucurbitane triterpene, 25,26,27-trinorcucurbit-5-ene-3,7,23-trione (3) were isolated from the methyl alcohol extract of the stems of Momordica charantia. The structures of the new compounds were elucidated by spectroscopic methods. Compounds 2 and 3 showed potent cytoprotective activity in tert-butyl hydroperoxide (t-BHP)-induced hepatotoxicity of HepG2 cells.

Compounds (I), (III) and (IV) exhibit promising cytotoxic activity against human hepatoma SK Hep-1 cells.

Four novel octanorcucurbitane triterpenes, octanorcucurbitacins A—D (1—4), together with one known octanorcucurbitane triterpene, kuguacin M (5), were isolated from the methyl alcohol extract of the stems of Momordica charantia. Their structures were elucidated on the basis of extensive spectroscopic analyses. Compound 3 inhibited tert-butyl hydroperoxide (t-BHP)-induced hepatotoxicity against HepG2 cells.

Two new fernane triterpenoids, 7alpha-hydroxyfern-8-en-11-one (1) and 11beta-hydroxyfern-8-en-7-one (2), and two new filicane triterpenoids, 3beta-hydroxyfilic-4(23)-ene (3) and filicenol (5), together with one known filicane-type triterpenoid, 3alpha-hydroxyfilic-4(23)-ene (4), were isolated from the methyl alcohol extract of the leaves of Angiopteris palmiformis. Their structures were elucidated on the basis of extensive analyses of their spectroscopic data (NMR, MS, IR) and comparison with spectroscopic data in the literature.

A new phenolic, (4-hydroxy-2-isopropylphenyl)ethanoic acid and a new lignan, epi-calocedrin were obtained from the roots of Juniperus chinensis Linn. The structures were elucidated on the basis of spectroscopic analysis and chemical evidence.

Four new D:C-friedooleanane-type triterpenes, 3β-O-(E)-feruloyl-D:C-friedooleana-7,9(11)-dien-29-ol (1), 3β-O-(E)-coumaroyl-D:C-friedooleana-7,9(11)-dien-29-ol (2), 3β-O-(E)-coumaroyl-D:C-friedooleana-7,9(11)-dien-29-oic acid (3), and methyl 2β,3β-dihydroxy-D:C-friedoolean-8-en-29-oate (6), together with five known triterpenes with the same skeleton, 3-epikarounidiol (4), 3-oxo-D:C-friedoolena-7,9(11)-dien-29-oic acid (5), bryonolol (7), bryononic acid (8), and 20-epibryonolic acid (9), were isolated from the methanol extract of the stems of Lagenaria siceraria. The structures of those compounds were elucidated using spectroscopic methods. Compounds 3 and 9 showed significant cytotoxic activity against the SK-Hep 1 cell line with IC50 values of 4.8 and 2.1 μg/ml, respectively. Based on these initially promising results, the two D:C-friedooleanane triterpenes merit further study as potential anticancer agents.

Four new cucurbitane-type triterpenes, cucurbita-5,23(E)-diene-3beta,7beta,25-triol (1), 3beta-acetoxy-7beta-methoxycucurbita-5,23(E)-dien-25-ol (2), cucurbita-5(10),6,23(E)-triene-3beta,25-diol (5), and cucurbita-5,24-diene-3,7,23-trione (6), together with four known triterpenes, 3beta,25-dihydroxy-7beta-methoxycucurbita-5,23(E)-diene (3), 3beta-hydroxy-7beta,25-dimethoxycucurbita-5,23(E)-diene (4), 3beta,7beta,25-trihydroxycucurbita-5,23(E)-dien-19-al (7), and 25-methoxy-3beta,7beta-dihydroxycucurbita-5,23(E)-dien-19-al (8), were isolated from the methyl alcohol extract of the stems of Momordica charantia. The structures of the new compounds were elucidated by spectroscopic methods.

Four new D:C-friedooleanane-type triterpenes, 3 beta-O-(E)-feruloyl-D:C-friedooleana-7,9(11)-dien-29-ol (1), 3 beta-O-(E)-coumaroyl-D:C-friedooleana-7,9(11)-dien-29-ol (2), 3 beta-O-(E)-coumaroyl-D:C-friedooleana-7,9(11)-dien-29-oic acid (3), and methyl 2 beta,3 beta-dihydroxy-D:C-friedoolean-8-en-29-oate (6), together with five known triterpenes with the same skeleton, 3-epikarounidiol (4), 3-oxo-D:C-friedoolena-7,9(11)-dien-29-oic acid (5), bryonolol (7), bryononic acid (8), and 20-epibryonolic acid (9), were isolated from the methanol extract of the stems of Lagenaria siceraria. The structures of those compounds were elucidated using spectroscopic methods. Compounds 3 and 9 showed significant cytotoxic activity against the SK-Hep 1 cell line with IC50 values of 4.8 and 2.1 microg/ml, respectively. Based on these initially promising results, the two D:C-friedooleanane triterpenes merit further study as potential anticancer agents.

Four new lanostane-type triterpenes, 24-ethyl-3beta-methoxylanost-9(11)-en-25-ol (1), 3beta-methoxy-24-methylenelanost-9(11)-en-25-ol (2), 3beta-methoxy-25-methyl-24-methylenelanost-9(11)-en-21-ol (3) and 3beta-methoxy-24-methyllanosta-9(11),25-dien-24-ol (4) together with three known triterpenes, betulinaldehyde, betulinic acid methyl ester, and ursaldehyde have been isolated from the methanol extract of the twigs of Diospyros discolor. The structures of those new compounds were elucidated by spectroscopic methods.

Two new 27-norcucurbitane triterpenoids, 27-nor-3beta-hydroxy-7beta-methoxycucurbita-5,23(E)-dien-25-one (1) and 27-nor-3beta-hydroxy-5beta,19-epoxycucurbita-6,23(E)-dien-25-one (2), together with two known cucurbitane triterpenes, 23(E)-7beta-methoxycucurbita-5,23,25-trien-3beta-ol (3) and 5beta,19-epoxy-25-methoxycucurbita-6,23(E)-dien-3beta-ol (4), were isolated from the fruits of Momordica charantia var. abbreviata. Their structures were determined by analysis of spectroscopic data and comparison with the data of known analogues.

A new phenolic, (4-hydroxy-2-isopropylphenyl)ethanoic acid and a new lignan, epi-calocedrin were obtained from the roots of Juniperus chinensis Linn. The structures were elucidated on the basis of spectroscopic analysis and chemical evidence.