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An efficient approach to access chiral N-α indole substituted pyrrolidine and piperidine skeletons has been developed through a AgSbF6-catalyzed N-α aza-Friedel–Crafts alkylation of N,O-acetals 6a, 6b, 9, and 11a–11d with indoles.

An efficient approach to functionalized (

An efficient approach to access α-arylacetylene-substituted pyrrolidine and piperidine derivatives has been developed through a samarium diiodide-mediated addition–elimination process of N-α-radicals with arylacetylene sulfones.

A catalyzed process for the synthesis of the 4,6-substituted 3,4-dihydro-1,3-oxazin-2-one skeleton has been developed through cycloaddition of in situ generated acyliminium intermediates with alkynes.

A unique prenylated bicarbazole alkaloid, clausanisumine (1), and two biogenetically related known monomer carbazole alkaloids, mukonal (2) and 3-methylcarbazole (3), were isolated from the fruits of Clausena anisum-olens. Clausanisumine (1) was an uncommon prenylated bicarbazole alkaloid, possessing an unprecedented carbon skeleton, which was composed of a simple carbazole alkaloid and a prenylated carbazole alkaloid. The chemical structure of 1 was established by a combination of comprehensive spectral methods. A plausible biosynthetic pathway of 1 was also proposed. Additionally, the potential anti-HIV activities of all isolates 1-3in vitro were evaluated. Compound 1 exhibited remarkable anti-HIV-1 reverse transcriptase effects showing an EC50 value of 18.58 nM. The discovery of the prenylated bicarbazole alkaloid from C. anisum-olens with notable anti-HIV activity would be meaningful to discovering and developing new anti-HIV drugs.

A novel approach to 2-substituted-2-(dimethoxyphosphoryl)-pyrrolidines 7a-7o and 9a-9r has been developed, which features a TMSOTf-mediated one-pot intramolecular cyclization and phosphonylation of substituted tert-butyl 4-oxobutylcarbamates. The major advantages of this method include simple operation under mild reaction conditions, the use of cheap Lewis acid, and good to excellent yields with high diastereoselectivities (dr up to 99:1).

An efficient approach to access α-arylacetylene-substituted pyrrolidine and piperidine derivatives has been developed through a samarium diiodide-mediated addition-elimination process of pyrrolidine and piperidine

The present study established a determination method of Psoraleae Fructus by quantitative analysis of multi-components by the single marker(QAMS) and further improved the thin-layer chromatography(TLC) method. The QAMS method was established by UPLC with psoralen as the internal marker, and the content of psoralenoside, isopsoralenoside, psoralen, and isopsoralen was simultaneously determined. As revealed by the comparison with results of the external standard method, the QAMS method was accurate and feasible. According to the current quality standards of Psoraleae Fructus, the TLC method was further optimized and improved, and bakuchiol was added for identification based on the original TLC method with psoralen and isopsoralen as indicators. This study provides a reference for improving the quality control method of Psoraleae Fructus.

A catalyzed process for the synthesis of the 4,6-substituted 3,4-dihydro-1,3-oxazin-2-one skeleton has been developed through cycloaddition of

Toona sinensis, popularly known as Chinese toon or Chinese mahogany, is a perennial deciduous arbor belonging to the genus Toona in the Meliaceae family, which is widely distributed and cultivated in eastern and southeastern Asia. Its fresh young leaves and buds have been consumed as a very popular nutritious vegetable in China and confirmed to display a wide variety of biological activities. To investigate the chemical constituents and their potential health benefits from the fresh young leaves and buds of T. sinensis, a phytochemical study on its fresh young leaves and buds was therefore undertaken. In our current investigation, 16 limonoids (1-16), including four new limonoids, toonasinenoids A-D (1-4), and a new naturally occurring limonoid, toonasinenoid E (5), were isolated and characterized from the fresh young leaves and buds of T. sinensis. The chemical structures and absolute configurations of limonoids 1-5 were elucidated by comprehensive spectroscopic data analyses. All known limonoids (6-16) were identified via comparing their experimental spectral data containing mass spectrometry data, 1H and 13C nuclear magnetic resonance data, and optical rotation values to the data reported in the literature. All known limonoids (6-16) were isolated from T. sinensis for the first time. Furthermore, the neuroprotective effects of all isolated limonoids 1-16 against 6-hydroxydopamine-induced cell death in human neuroblastoma SH-SY5Y cells were assessed in vitro. Limonoids 1-16 exhibited notable neuroprotective activities, with EC50 values in the range from 0.27 ± 0.03 to 17.28 ± 0.16 μM. These results suggest that regular consumption of the fresh young leaves and buds of T. sinensis might prevent the occurrence and development of Parkinson's disease (PD). Moreover, the isolation and characterization of these limonoids that exhibit notable neuroprotective activities from the fresh young leaves and buds of T. sinensis could be very significant for researching and developing new neuroprotective drugs used for the prevention and treatment of PD.

Infertility has got to be a broadly concerned social issue these days, in which the malefactor cannot be overlooked. Numerous studies have shown that electromagnetic pulse (EMP) radiation may have seriously damaging effects on reproductive health, through nonthermal effects and oxidative stress. Molecular hydrogen, a selective hydroxyl radical scavenger, explains the protective effects against many diseases closely associated with oxidative damage, such as ionizing radiation (IR). We sought to characterize the beneficial effects of molecular hydrogen on the male reproductive system in a rodent EMP exposure model. The 8-week-old male Sprague-Dawley rats were exposed to EMP (peak intensity 1000 kV/m, pulse edge 20 ns, pulse width 200 ns, 1 Hz, and 200 pulses), with or without hydrogen-rich water. The pathological structure of the testis, the rate of apoptosis of the testis, the serum testosterone level, the sperm parameters, and the activity of the antioxidant enzymes of the testis were measured. Then, transcriptomic and untargeted metabolomic analyses were applied to uncover the underlying mechanism. Exposure to EMP increased testicular apoptosis rate and apoptosis protein level, decreased sperm viability and motility, decreased serum testosterone levels, and diminished testicular antioxidant capacity. Molecular hydrogen-alleviated damage decreased the testicular apoptosis rate and apoptosis protein level, increased sperm motility, increased serum testosterone levels, and improved antioxidative capacity. Omics results showed that molecular hydrogen has a strong influence on metabolic pathways, and EMP affects mainly oxidative phosphorylation, TNF signaling pathways, and cytokine-receptor interactions. The mechanism of molecular hydrogen’s effect may be related to the reversal of some metabolite levels. These observations warrant molecular hydrogen as an innovative approach for potential protection against EMP.

Regioselective C-H alkenylation of

A unique prenylated bicarbazole alkaloid, clausanisumine (

In this study, we proposed a simple and effective sodium perborate (SPB) pretreatment method to enhance the enzymatic hydrolysis efficiency of rice straw (RS). The lignin removal rate reached 45.76% under the optimum pretreatment conditions of 8% SPB and 80 °C for 4 h, and the enzymatic hydrolysis efficiency of pretreated RS was 84% at a cellulase loading of 20 FPU/g RS. Through simultaneous saccharification and co-fermentation (SScF) of the pretreated RS solid with Saccharomyces cerevisiae SHY07-1, the maximum ethanol concentration was 15.29 g/L at 72 h, with a fermentation efficiency as high as 91.96%. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR) analyses revealed that the RS structure was destroyed by SPB pretreatment, and lignin was effectively removed. The overall data of this study indicate that SPB pretreatment is a promising method to improve enzymatic hydrolysis and bioethanol production from RS by inoculating Saccharomyces cerevisiae SHY07-1.

Artocarpus heterophyllus (jack tree) is an evergreen fruit tree belonging to the genus Artocarpus (Moraceae), which is widely distributed in subtropical and tropical regions of Asia. Its fruits (jackfruit), well-known as the world's largest tree-borne fruit, are being consumed in our daily diets as a very popular tropical fruit throughout the world and have been confirmed to hold various health benefits. In this study, five new prenylated chromones, artocarheterones A-E (1-5), as well as seven known prenylated chromones (6-12) were purified and isolated from the ripe fruits of A. heterophyllus (jackfruit). Their chemical structures were determined through comprehensive spectroscopic methods. This is the first report on prenylated chromones isolated from A. heterophyllus. The anti-HIV-1 effects of all isolated chromones were assessed in vitro. As a result, prenylated chromones (1-12) showed remarkable anti-HIV-1 effects with EC50 values ranging from 0.09 to 9.72 μM. These research results indicate that the isolation and characterization of these prenylated chromones with remarkable anti-HIV-1 activities from the ripe fruits of A. heterophyllus could be significant to the discovery and development of new anti-HIV-1 drugs.

Manilkara zapota, usually known as Sapodilla, is a fairly slow-growing evergreen tropical tree which belongs to the genus Manilkara (Sapotaceae), indigenous to Central America, southern Mexico, and the Caribbean. The ripe fruits of M. zapota have been widely consumed as an uniquely flavored tropical fruit and verified to hold a variety of health benefits. In order to investigate the potential health-promoting chemical compositions from the fruits of M. zapota cultivated in Hainan Island of China, a systematic and in-depth phytochemical study on this fruit was accordingly implemented. In our current study, three new prenylated coumarins, manizapotins A-C (1-3), together with seven known prenylated coumarins (4-10), were separated from the fruits of M. zapota. The chemical structures of new prenylated coumarins 1-3 were unambiguously established by means of comprehensive spectroscopic analyses, and the known compounds 4-10 were determined by comparing their experimental spectral data with those described data in the literature. This is the first time to discover prenylated coumarins occurring in M. zapota. The potential anti-inflammatory effects and anti-HIV (human immunodeficiency virus) activities of all these separated prenylated coumarins were assessed. Prenylated coumarins 1-10 dispalyed remarkable inhibitory effects against nitric oxide production induced by lipopolysaccharide in mouse macrophage RAW 264.7 cells with the IC50 values equivalent to that of hydrocortisone in vitro. Meanwhile, prenylated coumarins 1-10 exhibited pronounced anti-HIV-1 reverse transcriptase activities with the EC50 values in range of 0.12-8.69 μM. These results suggest that appropriate and reasonable consumption of the fruits of M. zapota might assist people to prevent and reduce the occurrence of inflammatory diseases together with the infection of HIV. Furthermore, the discovery of these prenylated coumarins from the fruits of M. zapota holding pronounced anti-inflammatory effects along with anti-HIV activities could be of great significance to the research and development of new natural anti-inflammatory and anti-HIV agents.

The chemical constituents from the stems and leaves of Clausena excavata were isolated and purified by column chromatography with silica gel, ODS, Sephadex LH-20 and RP-HPLC. The chemical structures of the isolated compounds were identified on the basis of physicochemical properties, spectroscopic analysis, as well as the comparisons with the data reported in literature. Nineteen compounds were isolated from the 90% ethanol extract of the stems and leaves of C. excavata, which were identified as methyl orsellinate(1), syringaresinol(2), lenisin A(3), scopoletin(4), osthenol(5), N-benzoyltyrarnine methyl ether(6), N-p-coumaroyltyramine(7), aurantiamide acetate(8), 1H-indole-3-carboxaldehyde(9), furostifoline(10), clausenalansine E(11), 3-formylcarbazole(12), clausine L(13), clausine E(14), methyl carbazole-3-carboxylate(15), glycosinin(16), murrayafoline A(17), clausine H(18) and 2,7-dihydroxy-3-formyl-1-(3'-methyl-2'-butenyl)carbazole(19). Among these isolated compounds, compounds 1-11 were isolated from C. excavata for the first time, and compounds 1, 2 and 10 were isolated from the genus Clausena for the first time. In addition, this study evaluated the anti-rheumatoid arthritis activities of compounds 1-19 by measuring their anti-proliferative effects on synoviocytes in vitro according to MTS method. Compounds 10-19 displayed remarkable anti-rheumatoid arthritis activities, which exhibited the inhibitory effects on the proliferation of MH7 A synovial fibroblast cells with the IC_(50) values ranging from(27.63±0.18) to(235.67±2.16) μmol·L~(-1).

A novel approach to 2-substituted-2-(dimethoxyphosphoryl)-pyrrolidines

Clausena lansium, also known as wampee, is a species of strongly scented evergreen trees belonging to the genus Clausena (Rutaceae), which is native to southern China. Its ripe fruits have been consumed as a very popular fruit and reported to possess a range of biological activities. To study the potential health-promoting constituents from the fruits of C. lansium, a chemical investigation on its fruits was thus carried out. In this study, 16 carbazole alkaloids (1-16), including six new carbazole alkaloids, clausenalansines A-F (1-6), were separated from the fruits of C. lansium. The molecular structures of these isolated new carbazole alkaloids (1-6) were ambiguously established on the basis of comprehensive spectroscopic methods. The known analogues (7-16) were determined via comparing their experimental data with those described in the literature, which were separated from C. lansium for the first time. All these isolated alkaloids were tested in vitro for their neuroprotective effects against 6-hydroxydopamine induced cell death in human neuroblastoma SH-SY5Y cells. Carbazole alkaloids 1-16 displayed remarkable neuroprotective effects possessing the EC50 values ranging from 0.36 ± 0.02 to 10.69 ± 0.15 μM. These findings indicate that regular consumption of the fruits of C. lansium may help people prevent the occurrence of Parkinson's disease. In addition, the separation and identification of these carbazole alkaloids possessing remarkable neuroprotective effects from the fruits of C. lansium could be extremely important to the discovery of new agents for the prevention and treatment of Parkinson's disease.

Ficus carica is an Asian species of flowering plant belonging to the genus Ficus of the family Moraceae, native to Western Asia and the Middle East. Its fruits, usually known as common fig or fig, have been consumed as a very popular health-promoting fruit worldwide since ancient times. To investigate the potential health-promoting chemical constituents of the fruits of F. carica, a systematic phytochemical study on its fruits was therefore carried out. In our study, four new structurally diverse prenylated isoflavone derivatives, ficucaricones A-D (1-4), along with 12 known analogues (5-16) were separated from the fruits of F. carica. Their chemical structures were ambiguously elucidated based on extensive spectroscopic methods. The anti-inflammatory effects and antiproliferative activities of these isolated prenylated isoflavone derivatives were tested. Prenylated isoflavone derivatives (1-16) displayed remarkable inhibitory effects against nitric oxide (NO) production with the IC50 values ranging from 0.89 ± 0.05 to 8.49 ± 0.18 μM, comparable to that of the positive control (hydrocortisone). Furthermore, compounds 1-16 also exhibited pronounced antiproliferative activities against diverse human cancer cell lines in vitro, holding the IC50 values ranging from 0.18 ± 0.03 to 18.76 ± 0.09 μM. These findings indicate that regular consumption of the fruits of F. carica may help to prevent the occurrence of inflammatory diseases and tumors. Moreover, the isolation and characterization of these prenylated isoflavone derivatives possessing remarkable anti-inflammatory effects and antiproliferative activities could be meaningful to the discovery of new anti-inflammatory and antitumor agents.

The investigation on the stems and leaves of Clausena sanki led to the isolation of a previously undescribed bisabolane sesquiterpene, clausemargic A (1), together with six known analogues (2-7). The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with data reported in the literature. All known compounds (2-7) were isolated from C. sanki for the first time. All isolated compounds were evaluated for their anti-inflammatory activities via examining the inhibitory activity on nitric oxide (NO) production induced by lipopolysaccharide in mouse macrophage RAW 264.7 cells in vitro. Compounds 1-7 showed significant inhibitory activities with IC50 values comparable to that of hydrocortisone.

The phytochemical investigation on the fruits of Clausena anisum-olens led to the isolation of 18 carbazole alkaloids (1–18), containing three new ones, clausenanisines A–C (1–3), and three new naturally occurring carbazole alkaloids, clausenanisines D–F (4–6), as well as 12 known analogues (7–18). The chemical structures of clausenanisines A–F (1–6) were elucidated by extensive spectroscopic methods. Notably, clausenanisine A (1) was a novel carbazole alkaloid with a unique five-membered cyclic ether, while clausenanisine E (5) is an unusual carbazole alkaloid owning an unprecedented naturally occurring carbon skeleton possessing 14 carbon atoms. The known carbazole alkaloids (7–18) were identified by the comparison of their spectral data with those data reported in the literature. All known carbazole alkaloids 7–18 were isolated from C. anisum-olens for the first time. Moreover, all isolated compounds 1–18 were assessed for their protein tyrosine phosphatase 1B (PTP1B) and α-glucosidase inhibitory activities in vitro. Compounds 1–18 exhibited remarkable PTP1B inhibitory activities with IC50 values in the range of 0.58 ± 0.05 to 38.48 ± 0.32 μM, meanwhile, compounds 1–18 displayed significant α-glucosidase inhibitory activities with IC50 values ranging from 3.28 ± 0.16 to 192.23 ± 0.78 μM. These research results imply that the separation and identification of these carbazole alkaloids showing notable PTP1B and α-glucosidase inhibitory activities from the fruits of C. anisum-olens can be very significant for discovering and developing new PTP1B inhibitors and α-glucosidase inhibitors for the treatment of diabetes mellitus.

The chemical constituents from the stems and leaves of Clausena emarginata were separated and purified by column chromatographies on silica gel,ODS,Sephadex LH-20,and PR-HPLC. The structures of the isolated compounds were identified on the basis of physicochemical properties and spectroscopic analysis,as well as comparisons with the data reported in the literature. Sixteen compounds were isolated from the 90% ethanol extract of the stems and leaves of C. emarginata,which were identified as siamenol( 1),murrastanine A( 2),3-formyl-1,6-dimethoxycarbazole( 3),3-methoxymethylcarbazole( 4),3-methylcarbazole( 5),murrayafoline A( 6),3-formylcarbazole( 7),3-formyl-1-hydroxycarbazole( 8),3-formyl-6-methoxycarbazole( 9),murrayanine( 10),murrayacine( 11),girinimbine( 12),nordentatin( 13),chalepin( 14),8-hydroxy-6-methoxy-3-pentylisocoumarin( 15) and ethyl orsellinate( 16). Compounds 1-4,14-16 were isolated from C. emarginata for the first time. Among them,compounds 1,2,15 and 16 were isolated from the genus Clausena for the first time. All isolated compounds were evaluated for their cytotoxic activities against five human cancer cell lines: HL-60,SMMC-7721,A-549,MCF-7 and SW480 in vitro. Compounds 12 and 14 showed significant inhibitory effects against various human cancer cell lines with IC_(50) values comparable to those of doxorubicin.

Three new carbazole alkaloids, zanthoaustrones A–C (1–3), as well as nine known compounds 4–12, were isolated and characterized from the roots of Zanthoxylum austrosinense Huang (Rutaceae). Their chemical structures were elucidated on the basis of extensive and comprehensive spectroscopic methods, while the known alkaloids were identified by the comparison of their observed spectroscopic data including NMR data, MS data and optical rotation values with the data described in the literature. Furthermore, the antiproliferative activities as well as the anti-inflammatory effects of all isolated alkaloids in vitro were evaluated. All obtained alkaloids 1–12 displayed notable antiproliferative activities against diverse human cancer cell lines exhibiting IC50 values in range of 0.85 ± 0.06 to 29.56 ± 0.17 µM, which is equivalent to the positive control (cisplatin) showing IC50 values ranging from 1.58 ± 0.09 to 28.69 ± 0.21 µM. Moreover, compounds 1–12 exhibited pronounced inhibitory activities on nitric oxide (NO) production with IC50 values displaying IC50 values in range of 0.89 ± 0.05 to 9.62 ± 0.15 µM, which is comparable to the positive control (hydrocortisone) holding an IC50 value of 4.06 ± 0.11 µM. These findings indicate that the separation and characterization of these alkaloids displaying significant antiproliferative activities together with anti-inflammatory effects from the roots of Z. austrosinense could be meaningful to the research and development of new anti-cancer drugs as well as anti-inflammatory agents.

Clausena lansium (Lour.) Skeels is an evergreen small tree or shrub with great economic value, which belongs to the genus Clausena of the Rutaceae family. C. lansium is indigenous to Southern China, while currently widely cultivated in subtropical and tropical regions not only for the nutritional value and pharmacological uses of its fruits but also as a medicinal and ornamental plant. In this study, a systematic phytochemical study on the stems and leaves of C. lansium caused the separation and identification of two new geranylated carbazole alkaloids, clauselansiumines A (1) and B (2), as well as 10 known geranylated carbazole alkaloids (3–12). The chemical structures of these isolated geranylated carbazole alkaloids (1–12) were unambiguously determined based on comprehensive spectral data analyses. All these isolated geranylated carbazole alkaloids were tested for their neuroprotective effects against 6-hydroxydopamine induced cell death in human neuroblastoma SH-SY5Y cells in vitro. Compounds 1–12 displayed remarkable neuroprotective effects holding the EC50 values ranging from 0.48 ± 0.04 to 12.36 ± 0.16 μM. These research results disclosed that the separation and purification of these geranylated carbazole alkaloids possessing remarkable neuroprotective effects separated from C. lansium could be extremely important to the discovery of new agents for the treatment and prevention for Parkinson's disease.

Two iron precursors (iron(III) chloride and iron(II) ammonium sulfate) with a nitrogen-containing compound (ethylenediamine) were pyrolyzed on commercially available carbon blacks (Vulcan XC-72) under a nitrogen flow in this study. The properties of the resultant nonnoble electrocatalysts (Fe(Z)N/C-2 and Fe(Z)N/C-8) effected by using different iron precursors during the synthetic process were investigated by X-ray-based spectroscopies including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and X-ray absorption spectroscopy (XAS). The electrocatalytic performance toward oxygen reduction reaction (ORR) of these electrocatalysts was also comparatively studied by rotating disk electrode and chronoamperometric techniques. The obtained results indicate that iron precursors play an essential role on the chemical microstructure, elemental states, and ORR performance of electrocatalysts. The electrocatalysts (Fe(III)N/C-8) prepared by using iron(III) chloride as starting precursors exhibit better electrochemical ORR activity and durability among all the synthesized catalysts. As evidenced by XPS and XAS studies, we conclude that this may be due to the formation of active FeNx sites, more surface Fe/C and N/C atomic ratios, and the coexistence of pyridinic-N and graphitic-N species in the Fe(III)N/C-8 electrocatalyst.

The effect of Fe2O3 on the sintering property of MgO-CaO refractory was studied by XRD analysis and SEM analysis of sectioned specimens. As the content of ferric oxide increases, the specimen has higher density, lower porosity and the cold crush strength increases. In contrast the density and porosity of the fired specimens change slightly when the content is up to 6%. From XRD analysis, ferric oxide do not exist owing to that ferric oxide reacted with calcium oxide producing calcium ferrite; From SEM analysis, when the content of ferric oxide is 6%, calcium ferrite distributes uniformly between the main crystal phase and the matrix and the overall structure is homogeneous and dense. The result shows the nonuniform distribution of calcium ferrite as the content of ferric oxide is relatively low, while as the content of ferric oxide is high the excess amount of calcium ferrite existed in the sintered specimens will generate superfluous liquid phase to reduce the fire resistance of materials.

In this review of methods for purity assessment of isolated chromosome X- and Y-bearing sperm, we compared the principles, operating procedures, as well as pros and cons for various methods. We conclude that nested PCR of single sperm will become a conventional and popular method with lower costs, and the method will play a very important role in optimizing the X, Y sorting method, if the sensitivity and accuracy of the method can be increased and the testing time decreased, and promote the new progress in other genetic testing techniques on single sperm.