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https://www.readbyqxmd.com/read/28231014/cyclombandakamines-a1-and-a2-oxygen-bridged-naphthylisoquinoline-dimers-from-a-congolese-ancistrocladus-liana
#1
Blaise Kimbadi Lombe, Torsten Bruhn, Doris Feineis, Virima Mudogo, Reto Brun, Gerhard Bringmann
Cyclombandakamines A1 (1) and A2 (2), both with an unprecedented pyrane-cyclohexenone-dihydrofuran sequence and six stereocenters and two chiral axes, are the first oxygen-bridged dimeric naphthylisoquinoline alkaloids. They were isolated from the leaves of an as yet unidentified Congolese Ancistrocladus species. Their stereostructures were established by spectroscopic, chemical, and chiroptical methods in combination with DFT and TDDFT calculations. They apparently originate from a cascade of oxidative cyclization reactions of "open-chain" naphthylisoquinoline dimers and exhibit significant antiprotozoal activities...
February 23, 2017: Organic Letters
https://www.readbyqxmd.com/read/28231013/an-asymmetric-organocatalysis-approach-to-the-prenylated-alkaloid-family
#2
Matthew Rees, Nigel S Simpkins, Louise Male
Michael addition of a proline-derived triketopiperazine (TKP) to β-substituted enones and acrylamides, mediated by a cinchona alkaloid catalyst, delivers products possessing a bicyclo[2.2.2]diazaoctane structure in high yield and enantiomeric ratio (er). Further modification of the amide products toward polycyclic scaffolds resembling members of the prenylated alkaloid family is also demonstrated.
February 23, 2017: Organic Letters
https://www.readbyqxmd.com/read/28230296/plants-to-polyelectrolytes-theophylline-polymers-and-their-microsphere-synthesis
#3
Ryan Guterman, Markus Antonietti, Jiayin Yuan
To extend fossil oil supplies, sustainable feed stocks for the production of useful reagents and polymers should be harnessed. In this regard, chemicals derived from plants are excellent candidates. While the vast majority of plant sources used for polymer science only contain C x H y O z , alkaloids such as caffeine, nicotine, and theophylline possess nitrogen functionality that can provide new functions for bioderived polymers and their synthesis. In this context, the chemistry of theophylline, a natural product found in chocolate and tea, is exploited to create a cationic "poly(theophylline)" in a straightforward fashion for the first time...
February 23, 2017: Macromolecular Rapid Communications
https://www.readbyqxmd.com/read/28230294/asymmetric-total-syntheses-of-kopsia-indole-alkaloids
#4
Lingying Leng, Xiaohan Zhou, Qi Liao, Falu Wang, Hao Song, Dan Zhang, Xiao-Yu Liu, Yong Qin
The asymmetric total syntheses of a group of structurally complex Kopsia alkaloids, (-)-kopsine, (-)-isokopsine, (+)-methyl chanofruticosinate, (-)-fruticosine, and (-)-kopsanone, has been achieved. The key strategies for the construction of the molecular complexity in the targets included an asymmetric Tsuji-Trost rearrangement to set the first quaternary carbon center at C20, an intramolecular cyclopropanation by diazo decomposition to install the second and third quaternary carbon centers at C2 and C7, respectively, and a SmI2 -promoted acyloin condensation to assemble the isokopsine core...
February 23, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28229941/dual-high-resolution-inhibition-profiling-and-hplc-hrms-spe-nmr-analysis-for-identification-of-%C3%AE-glucosidase-and-radical-scavenging-inhibitors-in-solanum-americanum-mill
#5
Eder L Silva, Rita C Almeida-Lafetá, Ricardo M Borges, Dan Staerk
Solanum americanum is one of the most prominent species used to treat type 2 diabetes in Guatemala. In our ongoing efforts to find antidiabetic and antioxidative compounds from natural sources, an ethyl acetate extract of this medicinal herb was investigated using dual high-resolution α-glucosidase/radical scavenging inhibition profiling. The high-resolution biochromatograms obtained by this technique were used to target subsequent structural elucidation by HPLC-HRMS-SPE-NMR analysis towards the bioactive constituents...
February 13, 2017: Fitoterapia
https://www.readbyqxmd.com/read/28228365/isoquinoline-alkaloids-from-coptis-japonica-stimulate-the-myoblast-differentiation-via-p38-map-kinase-and-akt-signaling-pathway
#6
Heyjin Lee, Le Thi Tuong, Ji Hye Jeong, Sang-Jin Lee, Gyu-Un Bae, Jae-Ha Ryu
To overcome the muscle atrophy, such as cachexia and sarcopenia, we tried to find myogenic agents from medicinal plants. From myogenic extract of Coptis japonica, we purified six isoquinoline alkaloids and evaluated their effects on transactivation of myoD and MHC expression in C2C12 cells during differentiation process. Among obtained compounds, magnoflorine most efficiently enhanced the myoblast differentiation by activating the p38 MAP kinase and Akt pathway, and also increased the number of multinucleated and cylinder-shaped myotubes...
February 4, 2017: Bioorganic & Medicinal Chemistry Letters
https://www.readbyqxmd.com/read/28228097/alkaloid-extracts-from-combretum-zeyheri-inhibit-the-growth-of-mycobacterium-smegmatis
#7
Tafadzwa Nyambuya, Ruvimbo Mautsa, Stanley Mukanganyama
BACKGROUND: Current tuberculosis regimens have failed to combat the issue of drug resistance and ethno medicines may represent a possible source of antimycobacterial agents. Combretum species are well known in African traditional medicines and used for various ailments including pneumonia, venereal diseases like syphilis, mental problems, relief of sore throats and colds, fever, and chest coughs associated with tuberculosis. Alkaloids function as either hydrogen-acceptor or hydrogen-donor in hydrogen bonding critical for the interaction between targets thus, potentiating effects of curative agents on diseases...
February 23, 2017: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/28225280/-%C3%A2-uncarilins-a-and-b-dimeric-isoechinulin-type-alkaloids-from-uncaria-rhynchophylla
#8
Chang-An Geng, Xiao-Yan Huang, Yun-Bao Ma, Bo Hou, Tian-Ze Li, Xue-Mei Zhang, Ji-Jun Chen
(±)-Uncarilins A and B (1a/1b and 2a/2b), two pairs of unusual dimeric isoechinulin-type enantiomers with a symmetric four-membered core, were isolated from Uncaria rhynchophylla driven by LCMS-IT-TOF analyses. Their structures were elucidated by extensive 1D and 2D NMR spectra, X-ray diffraction, and ECD spectroscopic data. (-)-Uncarilin B (2a) showed activities on MT1 and MT2 receptors with agonistic rates of 11.26% and 52.44% at a concentration of 0.25 mM.
February 22, 2017: Journal of Natural Products
https://www.readbyqxmd.com/read/28225144/molecular-and-genetic-basis-for-early-stage-structural-diversifications-in-hapalindole-type-alkaloid-biogenesis
#9
Qin Zhu, Xinyu Liu
Heterologous expressions and purifications of all WelU proteins from the welwitindolinone pathways in Hapalosiphon welwitschii UTEX B1830 and IC-52-3 led to the discovery that WelU1 and WelU3 selectively assemble 12-epi-fischerindole U (2) and 12-epi-hapalindole C (1), respectively, from 3-geranyl 3-isocyanovinyl indolenine (4) via an enzymatic cascade featuring the Cope rearrangement, stereoselective aza-Prins cyclization and regioselective carbocation deposition. In combination with the in vitro characterization of WelU1/WelU3-homolog AmbU4 for the biogenesis of 12-epi-hapalindole U, this study provide a unified view on the origin of the early stage structural diversifications in hapalindole-type alkaloid biosynthesis, post common intermediate 4...
February 22, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/28223996/untargeted-metabotyping-lolium-perenne-reveals-population-level-variation-in-plant-flavonoids-and-alkaloids
#10
Mingshu Cao, Karl Fraser, Chris Jones, Alan Stewart, Thomas Lyons, Marty Faville, Brent Barrett
Metabolomics provides a powerful platform to characterize plants at the biochemical level, allowing a search for underlying genes and associations with higher level complex traits such as yield and nutritional value. Efficient and reliable methods to characterize metabolic variation in economically important species are considered of high value to the evaluation and prioritization of germplasm and breeding lines. In this investigation, a large-scale metabolomic survey was performed on a collection of diverse perennial ryegrass (Lolium perenne L...
2017: Frontiers in Plant Science
https://www.readbyqxmd.com/read/28223695/the-mirnaome-of-catharanthus-roseus-identification-expression-analysis-and-potential-roles-of-micrornas-in-regulation-of-terpenoid-indole-alkaloid-biosynthesis
#11
Ethan M Shen, Sanjay K Singh, Jayadri S Ghosh, Barunava Patra, Priyanka Paul, Ling Yuan, Sitakanta Pattanaik
MicroRNAs (miRNAs) regulate numerous crucial biological processes in plants. However, information is limited on their involvement in the biosynthesis of specialized metabolites in plants, including Catharanthus roseus that produces a number of pharmaceutically valuable, bioactive terpenoid indole alkaloids (TIAs). Using small RNA-sequencing, we identified 181 conserved and 173 novel miRNAs (cro-miRNAs) in C. roseus seedlings. Genome-wide expression analysis revealed that a set of cro-miRNAs are differentially regulated in response to methyl jasmonate (MeJA)...
February 22, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28223223/berberine-improves-cognitive-impairment-by-promoting-autophagic-clearance-and-inhibiting-production-of-%C3%AE-amyloid-in-app-tau-ps1-mouse-model-of-alzheimer-s-disease
#12
Min Huang, Xin Jiang, Yubin Liang, Qiong Liu, Siyan Chen, Yi Guo
This study investigates the neuroprotective properties of berberine (a natural isoquinoline alkaloid isolated from the Rhizoma coptidis) and finds that berberine could promote β-amyloid (Aβ) clearance and inhibit Aβ production in the triple-transgenic mouse model of Alzheimer's disease (3×Tg-AD). During the study, berberine was first administrated to treat 3×Tg-AD mice and primary neurons. Morris water maze assay, western blotting, enzyme-linked immunosorbent assay (ELISA), immunofluorescence staining and histological analysis, transmission electron microscopic analysis were then used to evaluate the effects of the berberine administration...
February 20, 2017: Experimental Gerontology
https://www.readbyqxmd.com/read/28223119/neferine-augments-therapeutic-efficacy-of-cisplatin-through-ros-mediated-non-canonical-autophagy-in-human-lung-adenocarcinoma-a549%C3%A2-cells
#13
Sivalingam Kalai Selvi, Amirthalingam Vinoth, Thiyagarajan Varadharajan, Ching Feng Weng, Viswanadha Vijaya Padma
Combination of dietary components with chemotherapy drugs is an emerging new strategy for cancer therapy to increase antitumor responses. Neferine, major bisbenzylisoquinoline alkaloid isolated from the seed embryo of Nelumbo nucifera (Lotus). In the present study, we investigated the efficacy of the combinatorial regimen of neferine and cisplatin compared to cisplatin high dose in human lung adenocarcinoma (A549) cells. Co-treatment with neferine enhanced cisplatin-induced autophagy in A549 cells was accompanied by Acidic vesicular accumulation (AVO), enhanced generation of reactive oxygen species (ROS) and depletion of intracellular glutathione (GSH), down regulation of PI3K/AKT/mTOR pathway, conversion of LC3B-I to LC3B-II...
February 18, 2017: Food and Chemical Toxicology
https://www.readbyqxmd.com/read/28222487/pyrrole-derivatives-and-diterpene-alkaloids-from-the-south-china-sea-sponge-agelas-nakamurai
#14
Mei-Jun Chu, Xu-Li Tang, Guo-Fei Qin, Yan-Ting Sun, Lei Li, Nicole J de Voogd, Ping-Lin Li, Guo-Qiang Li
Two pairs of new non-brominated racematic pyrrole derivatives, (±)-nakamurine D (1) and (±)-nakamurine E (2), two new diterpene alkaloids, iso-agelasine C (16), and iso-agelasidine B (21), together with fifteen known pyrrole derivatives((±)-3 - 15), five known diterpene alkaloids (17 - 20, 22) were isolated from the South China Sea sponge Agelas nakamurai. The racemic mixtures, compounds 1 - 4, were resolved into four pairs of enantiomers, (+)-1 and (-)-1, (+)-2 and (-)-2, (+)-3 and (-)-3, and (+)-4 and (-)-4, by chiral HPLC...
February 21, 2017: Chemistry & Biodiversity
https://www.readbyqxmd.com/read/28222171/metabolite-profiling-of-the-carnivorous-pitcher-plants-darlingtonia-and-sarracenia
#15
Hannu Hotti, Peddinti Gopalacharyulu, Tuulikki Seppänen-Laakso, Heiko Rischer
Sarraceniaceae is a New World carnivorous plant family comprising three genera: Darlingtonia, Heliamphora, and Sarracenia. The plants occur in nutrient-poor environments and have developed insectivorous capability in order to supplement their nutrient uptake. Sarracenia flava contains the alkaloid coniine, otherwise only found in Conium maculatum, in which its biosynthesis has been studied, and several Aloe species. Its ecological role and biosynthetic origin in S. flava is speculative. The aim of the current research was to investigate the occurrence of coniine in Sarracenia and Darlingtonia and to identify common constituents of both genera, unique compounds for individual variants and floral scent chemicals...
2017: PloS One
https://www.readbyqxmd.com/read/28219593/betel-nut-chewing-is-associated-with-reduced-tacrolimus-concentration-in-taiwanese-liver-transplant-recipients
#16
W-Y Chen, C-Y Lee, P-Y Lin, C-E Hsieh, C-J Ko, K-H Lin, C-C Lin, Y-Z Ming, Y-L Chen
PURPOSE: Studies have shown that arecoline, the major alkaloid component of betel nuts, alters the activity of enzymes in the cytochrome P450 (CYP-450) family. Tacrolimus, an immunosuppressant that protects against organ rejection in transplant recipients, not only is mainly metabolized by CYP3A enzymes but also has a narrow therapeutic range. We aimed to investigate whether dose-adjusted blood trough levels of tacrolimus differed over time between betel nut-chewing and non-betel nut-chewing liver transplant recipients...
March 2017: Transplantation Proceedings
https://www.readbyqxmd.com/read/28219365/exploration-of-anti-cancer-effects-and-mechanisms-of-zuo-jin-wan-and-its-alkaloid-components-in-vitro-and-in-orthotopic-hepg2-xenograft-immunocompetent-mice
#17
Shun-Ting Chou, Chien-Yun Hsiang, Hsin-Yi Lo, Hui-Fen Huang, Ming-Tsung Lai, Ching-Liang Hsieh, Su-Yin Chiang, Tin-Yun Ho
BACKGROUND: Zuo-Jin-Wan (ZJW), a two-herb formula consisting of Coptis chinensis (CC) and Evodia rutaecarpa (ER), is commonly used in traditional Chinese medicine for the treatment of cancers. However, the efficacies and mechanisms of ZJW and its alkaloid components on cancers are still unclear. METHODS: Here we investigated the anti-cancer effects and mechanisms of ZJW, CC, ER, berberine, and evodiamine in cells and in intrahepatic xenograft mice. RESULTS: Treatment of HepG2 cells with ZJW, CC, ER, berberine, and evodiamine significantly displayed cytotoxic effects in a dose- and time-dependent manner...
February 20, 2017: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/28219006/ir-catalyzed-asymmetric-total-synthesis-of-communesin-f
#18
Xiao Liang, Tian-Yuan Zhang, Xue-Yi Zeng, Yu Zheng, Kun Wei, Yu-Rong Yang
The first catalytic asymmetric total synthesis of the heptacyclic alkaloid (-)-communesin F is described. A key step features an unprecedented iridium-catalyzed asymmetric intermolecular cascade cyclization, constructing the lower N,N-aminal-containing CDEF tetracyclic core in one step. Another notable element is the closure of final ring system (A ring) via a facile reduction of a twisted am-ide and concomitant cyclization activated by a mesylation of the N,O-hemiaminal intermediate.
February 20, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28218521/monoterpenoid-indole-alkaloids-from-kopsia-officinalis-and-the-immunosuppressive-activity-of-rhazinilam
#19
Ting Zeng, Xiu-Yin Wu, Shu-Xia Yang, Wei-Chun Lai, Shun-Dong Shi, Qiang Zou, Yang Liu, Li-Mei Li
Six new monoterpenoid indole alkaloids, kopsinidines C-E (1-3), 11,12-methylenedioxychanofruticosinic acid (4), 12-methoxychanofruticosinic acid (5), and N(4)-methylkopsininate (7), as well as chanofruticosinic acid (6, as a natural product) and 23 known alkaloids, were obtained from the twigs and leaves of Kopsia officinalis. Their structures were characterized by physical data analysis. All isolated compounds were evaluated for their immunosuppressive activity on human T cell proliferation. Rhazinilam (29) significantly inhibited human T cell proliferation activated by anti-CD3/anti-CD28 antibodies (IC50 = 1...
February 20, 2017: Journal of Natural Products
https://www.readbyqxmd.com/read/28217099/berberine-attenuates-intestinal-mucosal-barrier-dysfunction-in-type-2-diabetic-rats
#20
Jing Gong, Meilin Hu, Zhaoyi Huang, Ke Fang, Dingkun Wang, Qingjie Chen, Jingbin Li, Desen Yang, Xin Zou, Lijun Xu, Kaifu Wang, Hui Dong, Fuer Lu
Background: Intestinal mucosal barrier dysfunction plays an important role in the development of diabetes mellitus (DM). Berberine (BBR), a kind of isoquinoline alkaloid, is widely known to be effective for both DM and diarrhea. Here, we explored whether the anti-diabetic effect of BBR was related to the intestine mucosal barrier. Methods and Results: The rat model of T2DM was established by high glucose and fat diet feeding and intravenous injection of streptozocin. Then, those diabetic rats were treated with BBR at different concentrations for 9 weeks...
2017: Frontiers in Pharmacology
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