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Abstract: Four new terpenoids, nemoralisins D–G (1–4), were isolated from the leaves and stems of Aphanamixis grandifolia, along with two known diterpenoids, nemoralisin C and nemoralisin. Among them, compound 1 is the first example of norsesquiterpenoid with δ-lactone moiety, and nemoralisins E–G (2–4), are a class of acyclic diterpenoids, which are structurally related nemoralisin C and nemoralisin. These structures were established on the basis of spectroscopic methods and the absolute configuration of 1 was determined by comparison of quantum chemical TDDFT calculated and experimental ECD spectra. Nemoralisins D–G (1–4) were tested for their cytotoxicities on HL-60, SMMC-7721, A-549, MCF-7, and SW480 human tumor cell lines (IC50 >40 μM), as well as the antimicrobial activities on Staphylococcus aureus, Pseudomonas aeruginosa, MRSA92# and MRSA98# (MIC>50 μg/mL). [Copyright &y& Elsevier]

Abstract: Phytochemical investigation on the stems of Trigonostemon flavidus resulted in the isolation of five new 3,4-seco-diterpenoids, trigoflavidones A–E (1–5), structurally related to the main co-occurring known 3,4-seco-sonderianic acid (6) and 3,4-seco-sonderianol (7). Compound 4 possesses new 3,4-seco rearranged ent-pimarane skeletal type, characteristic of a vinyl group at C-8, while 5 features a unique five-membered ring (C1) fused with a cyclopropane ring (C2). The structures of the new compounds were established by a combination of spectroscopic data and computational methods. Compounds 1–7 were tested for their cytotoxicities on HL-60, SMMC-7721, A-549, MCF-7, and SW480 human tumor cell lines. [Copyright &y& Elsevier]

Abstract: Four vobasinyl–ibogan type bisindole alkaloids, ervachinines A–D (1–4), along with 12 known terpenoid indole alkaloids, were isolated from the whole plant of Ervatamia chinensis. Their structures were elucidated by analysis of spectroscopic data, including 1D and 2D NMR, and the absolute configurations of 1–4 were determined by CD exciton chirality method. All of the compounds were evaluated for in vitro cytotoxicity against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480. Bisindole alkaloids 1–6 exhibited inhibitory effects, with IC50 values comparable to those of cisplatin. [Copyright &y& Elsevier]

The leaves of Garcinia rigida afforded six triterpenoid compounds, friedelin (1), lanosta-8,25-en-3β- ol (2), stigmasterol (3), lupeol (4), 3β-hydroxy-20(29)-en-lupan-30-al (5) and 3β-hydroxy-20(29)-en-lupan-30-ol (6). The structures of 1-6 were elucidated by IR, MS, NMR spectroscopies and comparison of their spectroscopic data with those reported in the literatures. Compound 6 showed toxicity to Artemia salina in brine shrimp lethality test (BLST) with LC50 27.72 µg/mL. [ABSTRACT FROM AUTHOR]

Abstract: Kansuinone (1), a rearranged euphane triterpenoid containing a spiro [5,6] ring system, was isolated from the roots of Euphorbia kansui. Its structure and stereochemistry were elucidated on the basis of spectroscopic, CD, and computational methods. Kansuinone (1) exhibited inhibitory activity against human and mouse 11β-HSD1 (11β-hydroxysteroid dehydrogenase type 1), with IC50 values of 1.12 and 1.08μM, respectively. [ABSTRACT FROM AUTHOR]

One new limonoid, toonaciliatone A (1), and one new tirucallane-type triterpenoid, toonaciliatine A (4), along with three known compounds, methyl-3β-acetoxy-1-oxomelic-14(15)-enate (2), perforin A (3), and cholest-14-ene-3,7,24,25-tetrol-21,23-epoxy-21-methoxy-4,4,8-trimethyl-3-(3-methyl-2-butenoate) (5), were isolated from the leaves of Toona ciliata. The structures of the new compounds were established by spectroscopic methods. [ABSTRACT FROM AUTHOR]

Abstract: Six new 8,14-seco-pregnane glycosides, gracillosides A–F (1–6), were isolated from the roots of Adelostemma gracillimum (Asclepiadaceae). All of them had the same aglycone as gracigenin with a rare 8,14-seco-pregnane type skeleton in nature and possessed an oligosaccharide chain consisting of four to six sugar units at C-3 of the aglycone. Their structures were determined on the basis of detailed spectroscopic analysis and chemical evidence. [Copyright &y& Elsevier]

Abstract: HDTMA+-pillared montmorillonites were obtained by pillaring different amounts of the surfactant hexadecyltrimethylammonium bromide (HDTMAB) into sodium montmorillonite (Na-Mt) in an aqueous solution. The optimum conditions and batch kinetics of sorption of p-nitrophenol from aqueous solutions are reported. The solution pH had a very important effect on the sorption of p-nitrophenol. The maximum p-nitrophenol absorption/adsorption occurs when solution pH (7.15–7.35) is approximately equal to the pK a (7.16) of the p-nitrophenol ion deprotonation reaction. X-ray diffraction analysis showed that surfactant cations had been pillared into the interlayer and the p-nitrophenol affected the arrangement of surfactant. With the increased concentration of surfactant cations, the arrangement of HDTMA+ within the clay interlayer changes and the sorption of p-nitrophenol increases. HDTMA+-pillared montmorillonites are more effective than Na-Mt for the adsorption of p-nitrophenol from aqueous solutions. The Langmuir, Freundlich and dual-mode sorption were tested to fit the sorption isotherms. [Copyright &y& Elsevier]

Three new lignan glycosides, mananthosides I-K (1-3), were isolated from the ethanolic extract of the aerial part of Mananthes patentiflora. The structure elucidation of these compounds was mainly established on the basis of 1D NMR, 2D NMR and HR-MS spectroscopic analysis. [ABSTRACT FROM AUTHOR]

Two new norbisabolane sesquiterpenoid glycosides, glochicoccinosides A (1) and B (2), together with two known compounds, have been isolated from the rhizomes of Glochidion coccineum. Their structures were elucidated by the combination of 1D NMR, 2D NMR, and MS spectral analysis, as well as chemical evidence. Cytotoxic activities and the antioxidant effect of these compounds were evaluated, but none of them showed activity. [ABSTRACT FROM AUTHOR]

Abstract: Two new C21-steroidal glycosides having hepta-saccharide residue were isolated from the rhizome of Cynanchum otophyllum Schneid. Their structures were determined to be caudatin 3-O-α-l-cymaropyranosyl-(1→4)-α-d-oleandropyranosyl-(1→4)-α-l-cymaropyranosyl-(1→4)-β-d-glucopyranosyl-(1→4)-α-d-oleandropyranosyl-(1→4)-β-d-oleandropyranosyl-(1→4)-β-d-diginopyranoside (1), and caudatin 3-O-β-d-cymaropyranosyl-(1→4)-α-d-oleandropyranosyl-(1→4)-α-l-cymaropyranosyl-(1→4)-β-d-glucopyranosyl-(1→4)-β-d-oleandropyranosyl-(1→4)-β-d-cymaropyranosyl-(1→4)-β-d-diginopyranoside (2) by spectral methods, respectively. [Copyright &y& Elsevier]

Abstract: An unusual yuzurine-type alkaloid daphnilongerine (1), with an unprecedented fused pentacyclic skeleton in addition to seven known ones, daphnigracine (2), daphnezomine R, daphnigraciline, yuzurine, longistylumphyllines A, daphnilongeranin C, and calycinine A, was isolated from the fruits of Daphniphyllum longeracemosum. The structure and relative stereochemistry of 1 were determined by spectroscopic analysis. [Copyright &y& Elsevier]

Visible/Near Infrared Reflectance spectroscopy (350–2500 nm) is an efficient and effective tool to identify and semi-quantify clay minerals, Fe3+ (oxyhydr)oxides, and their crystal-chemistry/structure. Even so, there have been few studies systematically describing how spectroscopy can be applied to mineralogical evolution during weathering. This study investigated reflectance spectra of a long core of a thick basaltic weathering sequence in Hainan Island and a series of transformation products from montmorillonite to kaolinite to present spectral features associated with weathering trends. In combination with X-ray diffraction and geochemical results, mineralogical transitions and weathering intensity of the core samples were described from a spectroscopic perspective. Several different protoliths were spectroscopically recognized in the Hainan weathering sequence, consistent with geological observation and geochemical analysis. Overprinted on these multiple protoliths was a discernable weathering sequence observable by infrared spectroscopic methods. Clay minerals changed upwards in section from TOT type (nontronite) to TO type (kaolinite), and finally to O type (gibbsite) hydroxide clay-size particles as the result of gradual hydrolysis of silicates and leaching of mobile elements with weathering. The relative abundance of hydroxyl to interlayer water, observable by the band depth ratio of spectral absorptions around 1400 nm and 1900 nm (BD1400/BD1900), increased progressively and correlated positively with the chemical index of alteration and Al 2 O 3 concentration. The increasing BD1400/BD1900 index value with weathering was the result of gradual leaching of interlayer cations (e. g. Na+, K+), and their water complexes within interlayers, and gradual formation of M-OH layers by hydrolysis. Owing to leaching of Mg and release of Fe, the octahedral M-OH formed by hydrolysis was gradually dominated by Al-OH. Reflectance spectroscopy is a powerful tool to identify protolith changes in weathering sequences and for studying clay mineralogical transitions and weathering intensity. This spectroscopic approach could have great value for understanding weathering related to paleoclimate on Earth or other planets using field spectroscopy and remote sensing. • • Infrared reflectance spectroscopy was applied to a drill core through weathered rocks. • • Spectral indices of clay minerals were developed to characterize weathering trends. • • Ratios of spectral band depths measure interlayer water and hydroxyl content. • • These indices can be applied to remote sensing data of Mars. [ABSTRACT FROM AUTHOR]

Four new tirucallane-type triterpenoids, polystanins H–K (1–4), were obtained from the stems and leaves of Aphanamixis polystachya. Their structures were elucidated by analysis of the spectroscopic data and comparison with literature data. Compounds 1 and 2 showed week inhibitory effects against NO production in LPS-stimulated RAW264.7 cells. All the isolates were investigated for their antifungal activities against drug-resistant Candida albicans. [ABSTRACT FROM AUTHOR]

Abstract: Catharoseumine (1), a new monoterpenoid indole alkaloid possessing a unique peroxy bridge moiety, was isolated from the whole plants of Catharanthus roseus. Its structure was elucidated on the basis of NMR, IR, UV, and high-resolution mass spectrometric data, and its absolute configuration was determined by ECD and chemical methods. Catharoseumine (1) exhibited cytotoxicity against HL-60 cell line with IC50 value of 6.28μM and potential inhibition against Plasmodium falciparum falcipain-2 (IC50 =4.06μM). A plausible biogenetic pathway of 1 was also proposed. [Copyright &y& Elsevier]

Abstract: A new xanthone, yahyaxanthone (1), was isolated from Garcinia rigida leaves. Cytotoxicity evaluation showed that 1 was inhibitory to L1210 cell, with an IC50 value 4.08 μg/ml. [Copyright &y& Elsevier]

Abstract: A novel Daphniphyllum alkaloid with a rearranged fused-hexacyclic ring system, calycilactone A, was isolated from the leaves of Daphniphyllum calycillum (Daphniphyllaceae), and the structure and relative stereochemistry of the new compound were elucidated on the basis of spectroscopic data. [Copyright &y& Elsevier]

The aim of this study was to investigate the anti-inflammatory effects and mechanism of isovitexin on ulcerative colitis mice and RAW264.7 cells. The results showed that isovitexin had strong antioxidant and anti-inflammatory effects, and could restore intestinal barrier integrity (p < 0.01). In addition, isovitexin inhibited the expression of MyD88, TLR4 and NF-κB p65 proteins. At the same time, isovitexin can inhibit the activation of MAPK/NF-κB signaling pathway in RAW264.7 cells. In conclusion, isovitexin has a protective effect on UC mice, and its improvement mechanism of UC might be related to MAPK/NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

Two new aspidosperma-type monoterpenoid indole alkaloids, 16-O-methylvoafinine (1) and 14,15-diepi-voafinidine (2) were isolated from the aerial parts of Ervatamia officinalis. Their structures were established by comprehensive spectroscopic analysis including 1D and 2D NMR, HR-ESI-MS, and electronic circular dichroism calculation. The isolated compounds were evaluated for cytotoxic activities against HepG2, MCF-7, and A549 cell lines by CCK-8 assay. [ABSTRACT FROM AUTHOR]

Two new triucallane triterpenoids, polystanin F (1) and polystanin G (2), along with eight known compounds (3-10) were isolated from the fruits of Aphanamixis polystachya. Their structures were established on the basis of extensive spectroscopic analysis. Moreover, eight compounds were evaluated for their in vitro cytotoxicity against three cancer cell lines (liver cancer RT112, colon cancer HCT-116 and breast cancer M231) using the MTT method. Compound 7 showed significant cytotoxic activity against HCT-116 with IC50 1.27 μM. [ABSTRACT FROM AUTHOR]

isolation, structure and cytotoxicity [ABSTRACT FROM AUTHOR]

The phytochemical study of the fruiting bodies of Albatrellus confluens afforded a new natural product methyl 2-hydroxyimino-3- phenylpropionate (1), as well as 14 known compounds: phenylalanine (2), zarzissine (3), uridine (4), emeheterone (5), uracil (6), nicotinamide (7), adenosine (8)), methyl 4-hydroxyphenylacetate (9), grifolin (10), neogrifolin (11), grifolin methyl ether (12), 4-O-methyl grifolin acid (13), confluentin (14), albatrelin G (15). The structures of these compounds were deduced using spectroscopic methods, including IR, MS, 1D and 2D NMR, as well as by comparisons with data reported in the literature. Furthermore, the chemotaxonomic significance of the isolates was also discussed. • Fifteen compounds including a new compound were obtained. • Four compounds were isolated from the genus Albatrellus for the first time. • Five compounds were isolated from this species for the first time. • The chemotaxonomic significance of the isolates was discussed. [ABSTRACT FROM AUTHOR]

Preliminary studies reveal moderate cytotoxicity and potent antimalarial activity. [ABSTRACT FROM AUTHOR]

Highlights: [•] 16 daphnane-type and 15 known diterpenoids were isolated from Trigonostemon thyrsoideum. [•] They were various daphnane-type diterpenoids including with or without 9,12,14- or 9,13,14- or 12,13,14- orthoester moieties; oxetane ring and macrolactone moieties. [•] It includes with or without orthoester moieties, oxetane ring and macrolactone ones. [•] Five compounds showed potent anti-HIV-1 activities (EC50=0.015-0.001 nM; TI=1618–17,619). [Copyright &y& Elsevier]

RATIONALE Limonoids, a class of tetranortriterpenoids, exhibit various biological effects, including acting as potent antifeedants and insect growth-regulators against various pests. The analysis of phragmalin- and mexicanolide-type limonoids by collision-induced dissociation tandem mass spectrometry (CID-MS/MS) has not been reported. METHODS A high-performance liquid chromatography/electrospray ionization (HPLC/ESI)-MS/MS method was developed to investigate the fragmentation patterns of [M+NH4]+ ions for nine reference phragmalin- and mexicanolide-type limonoids. The method was also used in the identification of limonoid compounds in botanic extracts of Heynea trijuga. RESULTS The losses of side chains and the furan part were the major fragmentation patterns. However, there was variation in the relative abundances of product ions resulting from the same fragmentation pathways. A total of 89 phragmalin- and mexicanolide-type limonoids in botanic extracts of Heynea trijuga were detected and 50 of these compounds were identified or tentatively characterized based on elemental constituents, fragmentation pathways, and the profile of the major product ions of reference compounds. In addition, the isomers could be tentatively distinguished. CONCLUSIONS An HPLC/ESI-MS/MS method was developed and could be used to simultaneously identify and screen phragmalin- and mexicanolide-type limonoids in botanic extracts of Heynea trijuga. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A new 6/6/5/6-fused limonoid, phyllanthoid A (1), possessing both 19/30 and 19/29 oxygen bridges was isolated from Phyllanthus cochinchinensis(Euphorbiaceae), together with a new related limonoid, phyllanthoid B (2). Their structures were determined by spectroscopic analysis and single-crystal X-ray diffraction in the case of 1. Compound 1displayed moderate antifeedant against the generalist plant-feeding insect Spodoptera exiguaand cytotoxicity against the MCF-7 cell line. [ABSTRACT FROM AUTHOR]

A total of thirty-three surface water samples were collected from Meiliang Bay, Gonghu Bay and Xukou Bay of Lake Taihu, and analyzed for synthetic musks, including 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-[γ]-2-benzopyrane (HHCB), 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene (AHTN), 1- tert-butyl-3,5-dimethyl-2,5-dinitro-4-acetylbenzene (MK) and 1- tert-butyl-3,5-dimethyl-2,4,6-trinitrobenzene (MX). Ecological risks of these compounds were characterized by hazard quotient (HQ) method due to a lack of sufficient available toxicity data of synthetic musks. HHCB was the main synthetic musk detected in Lake Taihu, followed by AHTN, MK, and MX. The risk assessment results indicate that low ecological risks were posed by HHCB and total synthetic musks, and even lower risks posed by other synthetic musks in the worst case; much lower ecological risks were caused by both individual and total synthetic musks in the general case. The combined ecological risk from total synthetic musks calculation suggests that the combined ecological risk from all four synthetic musks was expected to be slightly higher than for the individual musks due to their joint action. The HQ spatial distribution maps show that several hot-spot areas were mainly around the river inlets to Lake Taihu, indicating that synthetic musks may be transported to Lake Taihu with municipal sewage and industrial wastewater from surrounding areas. However, the ecological risks in hot-spot areas posed by individual and total synthetic musks were still acceptable. [ABSTRACT FROM AUTHOR]

Abstract: The effect of the temperature (175, 185, 195 and 220°C) on the grafting of γ-aminopropyl triethoxysilane (APTES) on the interlayer hydroxyl groups of kaolinite pre-intercalated with DMSO were investigated using Fourier transform infrared spectroscopy, X-ray diffraction, thermal analysis and elemental analysis. The APTES-modified kaolinite prepared at 220°C showed a structure with high content of APTES and high thermal stability, in which the APTES molecules were grafted on to the inner-surface hydroxyl groups of kaolinite and arranged in the form of cross-linked monolayers. The APTES-modified kaolinites prepared at 175, 185 and 195°C exhibited inhomogeneous interlayer structure with pseudo-bilayer arrangements composed of grafted APTES molecules and hydrogen-bound DMSO or APTES molecules coexisting with monolayer arrangements. The monolayer arrangement of APTES corresponded to the basal spacing of about 1.00nm and the pseudo-bilayer arrangement 1.73–1.89nm. High reaction temperature was advantageous to the formation of the monolayer arrangement by promoting the exchange of the DMSO molecules by APTES molecules in the interlayer space of kaolinite, as well as the transformation of hydrogen-bound APTES molecules into grafted molecules. [Copyright &y& Elsevier]

Four new glycosylated compounds have been isolated from the whole plant of Tephroseris kirilowii, including ( - )-(1R,5R,6S,7R,8S)-8-O-β-d-glucopyranosyloxy-7-hydroxy-6-(2-hydroxypropan-2-yl)-9-methylenebicyclo[4.3.0]non-3-one (tephroside A, 1), ( - )-(1R,5R,6R,8R)-6-(2-O-β-d-glucopyranosyloxypropan-2-yl)-8-hydroxy-9-methylenebicyclo[4.3.0]non-3-one (tephroside B, 2), thesinine-4'-O-α-l-rhamnoside (3), and p-coumaric acid 4-O-α-l-rhamnoside (4), together with the known roseoside. The structures of the new compounds were established by means of spectroscopic analysis. [ABSTRACT FROM AUTHOR]

Four new carbohydrates were isolated from the acidic hydrolysis part of the ethyl acetate extract of Cynanchum otophyllum Schneid (Asclepiadaceae). Their structures were determined as methyl 2,6-dideoxy-3-O-methyl-β-d-arabino-hexopyranosyl-(1 → 4)-6-deoxy-3-O-methyl-β-d-ribo-hexopyranosyl-(1 → 4)-6-deoxy-3-O-methyl-α-l-ribo-hexopyranoside (1), methyl 6-deoxy-1,3-di-O-methyl-β-d-ribo-hexosyl-(1 → 4)-2,6-dideoxy-3-O-methyl-α-d-arabino-hexopyranoside (2), methyl 2,6-dideoxy-3-O-methyl-β-d-arabino-hexopyranosyl-(1 → 4)-6-deoxy-3-O-methyl-α-l-ribo-hexopyranoside (3), and 2,6-dideoxy-3-O-methyl-β-d-arabino-hexopyranosyl-(1 → 4)-2,6-dideoxy-3-O-methyl-α-d-arabino-hexopyranosyl-(1 → 4)-2,6-dideoxy-3-O-methyl-β-d-lyxo-hexopyranose (4), respectively, by spectral methods. [Copyright &y& Elsevier]

Nineteen triterpenoids, including five previously unknown (four triucallane-type derivatives and one highly oxidized A, B-seco limonoids), together with fourteen known triterpenoids, were isolated from the fruits of Aphanamixis polystachya. Their structures were elucidated by extensive spectroscopic analysis. All isolates were evaluated their anti-inflammatory activities. The result showed that all compounds inhibit LPS-induced nitric oxide production in RAW264.7 macrophages with their IC 50 value ranging from 95 to 1332 u M, and compound 6 exhibited obvious anti-inflammatory activity comparable to that of the positive control, with IC 50 values of 94.96 u M. Nineteen triterpenoids, including five previously unknown (four triucallane-type derivatives and one highly oxidized A,B-seco limonoids), together with fourteen known triterpenoids, were isolated from the fruits of Aphanamixis polystachya. Compound 6 exhibited obvious anti-inflammatory acitivity on LPS-induced in RAW264.7 cells at the concentration of 94.96 μM. [Display omitted] [ABSTRACT FROM AUTHOR]

Four new monoterpenoids, including two new acyclic monoterpenoids (2R, 6R)-2, 6-dimethyl-8-isovaleroxyoctan-1-ol (1) and (2S, 6S)-2, 6-dimethyl-8-isovaleroxyoctan-1-ol (2), as well as two new iridoids stenopterins F-G (3 and 4), together with fifteen known compounds (5–19), were isolated from whole dried material of Valeriana stenoptera. Stenopterin F was the first reported iridoids with n-butoxyl in the Valerianaceae family. The structures of new compounds were established on the basis of extensive spectroscopic analysis. [ABSTRACT FROM AUTHOR]

Abstract: Two novel alkaloids, trigonoine A containing a 2,8-diazabicyclo[3.3.1]nonane ring system and trigonoine B formed by a combination of a 2,3-dihydroquinolin-4-one and 3H-pyrrolo[2,3-c]quinoline rearranged from β-carboline skeleton were isolated from the leaves of Trigonostemon lii. Their structures were elucidated by 1D and 2D NMR spectroscopic methods. [Copyright &y& Elsevier]

A phytochemical investigation on the aerial parts of Ajuga macrosperma led to the isolation of a new diterpenoid, namely ajugamacrin F (1), along with eight known compounds, including one diterpenoid (2), one norsesquiterpenoid (3), one triterpenoid (4), three sterols (5 – 7), and two benzene derivatives (8 and 9). Their structures were established via spectroscopic analysis and comparison with literature data. Compounds 2 and 5 were obtained from A. macrosperma for the first time, and compounds 3 , 4 , 6 , 8 , and 9 were firstly reported from the genus Ajuga. Furthermore, the chemotaxonomic significance of these isolates was discussed. • Nine compounds were isolated from the aerial parts of Ajuga macrosperma. • A new neo -clerodane diterpenoid, ajugamacrin F (1), was discovered. • Two compounds were firstly obtained from A. macrosperma , and five compounds were firstly reported from the genus Ajuga. • The chemotaxonomic significance of these isolates was discussed. [ABSTRACT FROM AUTHOR]

This paper briefly examines current fundamental and applied research into clay minerals in China. A collection of studies from Chinese clay scientists and as a special issue suggests that investigations into the genesis and mineralogy of clay minerals for geology and geochemistry, synthetic clay minerals, the modification of clay minerals for advanced materials, comprehensive and reutilization of clay minerals are important aspects of fundamental and applied clay science within China. Effort is being made to increase the understanding of the genesis and evolution of clay minerals and such knowledge is believed to have scientific implication for paleogeographical, paleoecological, and paleoclimatic conditions and to have applications in mining and processing clay minerals and related environmental and ecological management. Studies on the modification of clay minerals by Chinese clay scientists aim predominantly to make functional clay mineral-polymer nanocomposites, adsorbents, catalysts, and biomaterials. In China, increasingly strict management of natural resources and environment, and an increasing demand for value-added clay-based products, along with the requirements for the sustainability of using clay mineral resources, offer opportunities and challenges to Chinese clay scientists and clay community. [ABSTRACT FROM AUTHOR]

Eight indole alkaloids, melosines A–H, together with 13 known alkaloids, were isolated from the fruits of Melodinus cochinchinensis . The structure elucidation of isolated secondary metabolites was based on comprehensive spectroscopic data analysis. Melosine B showed moderate cytotoxic activity against five human cancer cell lines, HL-60, SMMC-7721, A-549, MCF-7, and SW480 with IC 50 values ranging from 1.6 to 8.1 μM. [ABSTRACT FROM AUTHOR]

Terminalia chebula Retz is widely used by people because of its various pharmacological effects. In the present work, one undescribed gallate, namely terminaliate A (1), along with seven known compounds, including gallic acid (2), methyl gallate (3), three chebulic acid derivatives (4 – 6), 1,2,6-tri-O-galloyl-β-D-glucopyranose (7), and arjungenin (8), were isolated from the MeOH extract of the fruits of Terminalia chebula Retz. Their structures were elucidated based on spectroscopic methods, including IR, MS, 1D and 2D NMR, as well as by comparisons with data reported in the literature. Compounds 1 , 5 , and 6 reported from the family Combretaceae for the first time. All isolated compounds were evaluated for their α-glucosidase inhibitory effects. Furthermore, the chemotaxonomic significance of the isolates was also discussed. • Eight compounds including a new gallate were obtained. • Three compounds were isolated from this plant for the first time. • All isolated compounds were evaluated for their α-glucosidase inhibitory effects. • The chemotaxonomic significance of the isolates was discussed. [ABSTRACT FROM AUTHOR]

Four new eburnamine-aspidospermine type bisindole alkaloids, namely, mekongenines C–F (1–4), along with 27 known indole alkaloids were isolated from the twigs and leaves of Bousigonia mekongensis . Their structures with the absolute configurations were elucidated by spectroscopic methods and ECD analyses. All new compounds were evaluated for their cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Alkaloids 1–4 exhibited inhibitory effects with IC 50 values comparable to those of cisplatin. [ABSTRACT FROM AUTHOR]

Peganumine A (1), anew dimeric β-carbolinealkaloid characterized by a unique 3,9-diazatetracyclo[6.5.2.01,9.03,8]pentadec-2-one scaffold, was isolatedfrom the seeds of Peganum harmala. The structureincluding the absolute configuration was determined by spectroscopicdata, X-ray crystallography, ECD calculation, and CD exciton chiralityapproaches. Compound 1showed moderate cytotoxic activityagainst MCF-7, PC-3, and HepG2 cells and selective effects on HL-60cells with an IC50value of 5.8 μM. [ABSTRACT FROM AUTHOR]

A new limonoid, 3-de(2-methylbutanoyl)-3-propanoylcipadesin (1), along with 10 known limonoids and 1 known triterpenoid, was isolated from the fruits of Cipadessa cinerascens. Their structures were elucidated on the basis of spectroscopic analysis. All compounds were evaluated for their antimicrobial activities, and compounds 6 and 12 showed weak antimicrobial activities against MRSA 82# and MRSA 92#. [ABSTRACT FROM AUTHOR]

Abstract: Four new compounds, including three new steroids (1–3) and one new sesquiterpene (6), and two new natural products (4–5), as well as three known steroids (7–9) were isolated from the twigs of Turraea pubescens. Compounds 3–5 are C22 steroids isolated from the Meliaceae family for the first time. Their structures were elucidated by extensive NMR and MS analyses. Compound 1 exhibited inhibitory activity against lipopolysaccharide (LPS) induced nitric oxide (NO) production in RAW264.7 cells with an IC50 value of 11.5μM. [Copyright &y& Elsevier]

Highlights: [•] Thirteen daphnane-type diterpenoids were isolated from the stems of Trigonostemon lii. [•] The absolute stereochemistries of trigolins A–G were elucidated by CD spectra. [•] Eleven of the dapahnane compounds possess a rare 4, 6-oxetane moiety in the family of daphnane diterpenoids. [•] Four of the compounds displayed modest anti-HIV-1 activity in vitro. [ABSTRACT FROM AUTHOR]

Abstract: Five new yuzurimine-type Daphniphyllum alkaloids, daphmacromines K–O (1–5), were isolated from the leaves and stems of Daphniphyllum macropodum. Their structures were elucidated by extensive spectroscopic techniques, including 2D NMR spectroscopy and mass spectrometry. Daphmacromine O (5) showed moderate cytotoxic activity against brine shrimp. [ABSTRACT FROM AUTHOR]

Abstract: Five new yuzurimine-type Daphniphyllum alkaloids, daphmacromines K–O (1–5), were isolated from the leaves and stems of Daphniphyllum macropodum. Their structures were elucidated by extensive spectroscopic techniques, including 2D NMR spectroscopy and mass spectrometry. Daphmacromine O (5) showed moderate cytotoxic activity against brine shrimp. [Copyright &y& Elsevier]

Abstract: Phytochemical investigation of aerial parts of Glochidion assamicum Hook. f. led to the isolation of one new triterpenoid saponin, 3-O-[β-glucopyranosyl-(1→3)-α-arabinopyranosyl]-gymnestrogenin (assamicoside A, 7), and ten known compounds (1–6, 8–11). Their structures were identified by spectroscopic analysis and by comparison of their spectral data with those reported in the literature. The chemotaxonomic analysis is in agreement with previous work on the constituents of other Glochidion species. A spirostane-type C27 steroid (4) isolated from G. assamicum for the first time can be used to differentiate this species from other Glochidion. [Copyright &y& Elsevier]

Two new compounds, khayseneganin I (1) and 2α,3α,16β-trihydroxy-20-acetoxy-20(R)-pregnane (2), along with six known compounds, 2α,3α,20-trihydroxy-16β-acetoxy-20(R)-pregnane (3), 2α,3β-dihydroxypregnan-16-one-2β,19-hemiketal (4), (+)-catechin (5), ivorenolide A (6), luteolin-7-O-α-l-rhamnoside (7), and ( − )-5′-methoxy-isolariciresinol-2a-O-β-d-xylopyranoside (8), were isolated from the leaves and twigs ofKhaya senegalensis.The structures of new compounds were elucidated by 2D NMR spectroscopy and MS. Selected compounds (2–8) were evaluated for their antimicrobial activities and compounds5and7showed weak antimicrobial activities against MRSA 92#and MRSA 98#. [ABSTRACT FROM PUBLISHER]

Abstract: The anti hepatitis C virus (HCV) activity of (+)-lycoricidine (1) was evaluated for the first time in this letter, yielding an EC50 value of 0.55nmol/mL and an selection index (SI) value of 12.72. Further studies indicated that 1 induced this effect by down-regulating host heat-stress cognate 70 (Hsc70) expression. In addition, 20 derivatives were designed and synthesised to investigate the basic structure–activity relationship (SAR) of the title compound. Several of these derivatives exhibit a good inhibition of HCV, such as compound 3 (EC50 =0.68nmol/mL, SI=33.86), compound 2d (EC50 =15nmol/mL, SI=12) and compound 5 (EC50 =33nmol/mL, SI >10.91). Meanwhile, the experimental data suggest that the modification of certain groups of (+)-lycoricidine can reduce the cytotoxicity of the compounds. [Copyright &y& Elsevier]

Abstract: The calcined product of naturally occurring porous diatomite was previously assumed to be structure-destroyed or at least surface-reconstructed and therefore unsuitable for surface silylation. The present study indicates that the porosity of the mesoporous/macroporous diatomite remains intact after calcination at temperatures as high as 800°C, and the surface silylation of diatomite is achievable even for diatomite calcined at high temperatures. The interface interactions between the hydroxyl species of diatomite and γ-aminopropyltriethoxysilane (APTES) are significantly affected by heating pretreatment. Physically adsorbed water was largely preserved in diatomite at a low heating temperature, leading to the strong hydrolysis of APTES and the subsequent oligomerization between the hydrolyzed APTES species. Under heating at high temperature (800°C), the isolated silanols initially covered by water molecules were exposed and available for the direct grafting of APTES, forming a grafting-dominant structure with high thermal stability (540°C). The grafting-dominant diatomite had a much higher Cu(II) adsorption than the oligomerization-dominant type, because the coordination between the copper and nitrogen was stronger in the former case. These results demonstrate that heating pretreatment plays a key role in the surface silylation of diatomite, and that Cu(II) adsorption is highly dependent on the surface structure of the silylated diatomite. [Copyright &y& Elsevier]

Abstract: Three new cycloartane triterpenoids, aphagrandinoids A–C (1–3), and a new natural product, aphagrandinoid D (4), together with a known compound, were isolated from the leaves and twigs of Aphanamixis grandifolia. Their structures were elucidated by extensive NMR and MS techniques. Aphagrandinoid A (1), a 29-nor-cycloart triterpenoid, features with a sprio ring system at the side chain, while aphagrandinoid C (3) is a pentnortriterpenoid. Antibacterial activities of these five compounds were also evaluated. Compounds 1 and 5 showed weak antibacterial activities (MIC values: 1.57–3.13μg/mL) against Staphylococcus aureus, MRSA 92#, and MRSA 98#. [ABSTRACT FROM AUTHOR]