Read by QxMD icon Read


Hong Zhang, Zheng Dan, Zhi-Jie Ding, Yuan-Zhi Lao, Hong-Sheng Tan, Hong-Xi Xu
A UPLC-PDA-QTOFMS-guided isolation strategy was employed to screen and track potentially new compounds from Garcinia oblongifolia. As a result, two new prenylated xanthones, oblongixanthones D and E (1-2), six new prenylated benzoylphloroglucinol derivatives, oblongifolins V-Z (3-7) and oblongifolin AA (8), as well as a known compound oblongifolin L (9), were isolated from the EtOAc-soluble fraction of an acetone extract of the leaves of Garcinia oblongifolia guided by UPLC-PDA-QTOFMS analysis. The structures of the new compounds were elucidated by 1D- and 2D-NMR spectroscopic analysis and mass spectrometry...
October 21, 2016: Scientific Reports
Jessica M Wilson, Jeremy W Prokop, Ellen Lorimer, Elizabeth Ntantie, Carol L Williams
Two isoforms of the small GTPase Rap1, Rap1A and Rap1B, participate in cell adhesion; Rap1A promotes steady state adhesion, while Rap1B regulates dynamic changes in cell adhesion. These events depend on the prenylation of Rap1, which promotes its membrane localization. Here, we identify previously unsuspected differences in the regulation of prenylation of Rap1A versus Rap1B, due in part to their different phosphorylation-dependent interactions with the chaperone protein SmgGDS-607. Previous studies indicate that activation of Gαs protein-coupled receptors (GPCRs) phosphorylates S-179 and S-180 in the polybasic region (PBR) of Rap1B, which inhibits Rap1B binding to SmgGDS-607 and diminishes Rap1B prenylation and membrane localization...
October 16, 2016: Journal of Molecular Biology
Rocío López-Posadas, Cristina Mascaraque, Raquel González, María D Suárez, Antonio Zarzuelo, Olga Martínez-Augustin, Fermín Sánchez de Medina
BACKGROUND: Statins have antiinflammatory effects at the cardiovascular level because of inhibition of prenylation, which also probably underlies their therapeutic effects in preclinical models of inflammatory bowel disease. Another inhibitor of prenylation, namely alendronate, reduces colitis in rodents. In this study, we aim to explore the therapeutic potential of second-generation, nitrogen-containing bisphosphonates in 3 preclinical models of colitis. METHODS: The trinitrobenzenesulfonic acid and dextran sulfate sodium models of rat colitis and the adoptive lymphocyte transfer model of colitis in mice were used...
November 2016: Inflammatory Bowel Diseases
Anand Babu Velappan, Mamilla R Charan Raja, Dhrubajyoti Datta, Yi Ting Tsai, Iman Halloum, Baojie Wan, Laurent Kremer, Hugo Gramajo, Scott G Franzblau, Santanu Kar Mahapatra, Joy Debnath
Tuberculosis is a major threat for mankind and the emergence of resistance strain of Mycobacterium tuberculosis (Mtb) against first line antibiotics makes it lethal for human civilization. In this study, we have synthesized different diaryl urea derivatives targeting the inhibition of mycolic acid biosynthesis. Among the 39 synthesized molecules, compounds 46, 57, 58 and 86 showed MIC values ≤ 10 μg/ml against H37Rv and mc(2)6030 strains. The best molecule with a methyl at ortho position of the first aromatic ring and prenyl group at the meta position of the second aromatic ring showed the MIC value of 5...
September 26, 2016: European Journal of Medicinal Chemistry
Xue-Bi Cai, Xiu-Feng Huang, Yi Tong, Qin-Kang Lu, Zi-Bing Jin
Choroideremia is a bilateral and progressive X-linked inherited disease characterized by widespread chorioretinal atrophy with relative sparing of the macular region. It is caused by mutations in the ubiquitously expressed CHM gene, which lead to the absence of the Rab escort protein 1 (REP-1), resulting in prenylation deficiency. Typical fundus appearances for choroideremia were found in 3 probands from three unrelated Chinese families in our study. We firstly used the targeted exome sequencing (TES) technology to detect mutations in CHM gene...
October 14, 2016: Scientific Reports
Rauful Alam, Colin Diner, Sybrand Jonker, Lars Eriksson, Kálmán J Szabó
The catalytic asymmetric allylboration of cyclic imines with γ,γ-disubstituted allylboronic acids provides products with adjacent stereocenters in high yield and stereoselectivity. Various electrophiles, including 3,4-dihydroisoquinolines and indoles, were prenylated in a fully stereodivergent fashion by switching the E/Z geometry of the allylboronate and/or the enantiomer of the BINOL catalyst. 3-Methylindole provided products with three adjacent stereocenters with high stereoselectivity in one synthetic operation...
October 13, 2016: Angewandte Chemie
Christian Schem, Robert J Tower, Philipp Kneissl, Anna-Christina Rambow, Graeme M Campbell, Christine Desel, Timo Damm, Thorsten Heilmann, Sabine Fuchs, Maaz Zuharya, Anna Trauzold, Claus C Glüer, Sarah Schott, Sanjay Tiwari
Bisphosphonates have effects which are anti-resorptive, anti-tumor and anti-apoptotic to osteoblasts and osteocytes, but an effective means of eliciting these multiple activities in the treatment of bone metastases has not been identified. Antimetabolite-bisphosphonate conjugates have potential for improved performance as a class of bone specific anti-neoplastic drugs. The primary objective of the study was to determine whether an antimetabolite-bisphosphonate conjugate will preserve bone formation concomitant with anti-resorptive and anti-tumor activity...
October 7, 2016: Journal of Bone and Mineral Research: the Official Journal of the American Society for Bone and Mineral Research
Julia Winkelblech, Xiulan Xie, Shu-Ming Li
Prenylated secondary metabolites including indole derivatives usually demonstrate improved biological and pharmacological activities, which make them promising candidates for drug discovery and development. The transfer reactions of a prenyl moiety from a prenyl donor, e.g. dimethylallyl diphosphate (DMAPP), to an acceptor is catalysed by prenyltransferases. One special group of such enzymes uses DMAPP and tryptophan as substrates with dimethylallyltryptophans as reaction products and functions therefore as dimethylallyltryptophan synthases (DMATSs)...
October 18, 2016: Organic & Biomolecular Chemistry
Masahiro Okada, Tomotoshi Sugita, Kohei Akita, Yu Nakashima, Tian Tian, Chang Li, Takahiro Mori, Ikuro Abe
Prenylation is a key post-translational reaction to increase the structural diversity and bioactivity of peptides and proteins. Until now, only one post-translational modification enzyme, ComQ, has been identified to mediate the prenylation of a tryptophan residue in ribosomally synthesized peptides. Here, we report the in vitro characterization of KgpF, a novel prenyltransferase which transfers dimethylallyl moieties to tryptophan residues during kawaguchipeptin A biosynthesis. The stereospecific prenylation by KgpF was determined by a combination of in vitro dimethylallylation of Fmoc-tryptophan by KgpF and chemical synthesis of dimethylallylated Fmoc-tryptophan diastereomers...
October 12, 2016: Organic & Biomolecular Chemistry
J C Espinoza-Hicks, J M Nápoles-Duarte, G V Nevárez-Moorillón, A Camacho-Dávila, L M Rodríguez-Valdez
Novel chalcone derivatives with different substituents attached to A and B-rings: hydroxyl, methoxyl, geranyl, and prenyl groups were synthesized. The obtained compounds were characterized by NMR, HRMS, UV-Vis, IR, and MS. The theoretical analysis was carried out in all the compounds using density functional theory (DFT) with the B3LYP, PBE0, and M06-2X functionals in combination with the 6-311G(d,p) Pople-type basis set. The excited state properties were calculated by time dependent density functional theory (TD-DFT) using the same methodology applied for the ground state properties...
October 2016: Journal of Molecular Modeling
Fubo Han, Ik-Soo Lee
A new prenylated flavonol glycoside (1) was isolated from a 95% methanol extract of the dried and powdered aerial parts of Epimedium koreanum Nakai (Herba Epimedii), along with seven previously known flavonoids (2-8). The chemical structure of the new compound (1) was established to be 5-hydroxy-4'-methoxy-8-(2-hydroxy-3-methyl-3-butenyl)flavone 3-O-α-l-rhamnopyranosyl-7-O-β-D-gluco pyranoside on the basis of spectroscopic methods. The antioxidant activities of these compounds were determined by the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging assay and kaempferitrin (8) showed a high reactivity with DPPH...
October 3, 2016: Natural Product Research
Yuou Teng, Xuzhe Li, Ke Yang, Xuehui Li, Zijun Zhang, Luyao Wang, Zhijie Deng, Binbin Song, Zhihong Yan, Yongmin Zhang, Kui Lu, Peng Yu
Four ring-closed analogs of natural prenylated chalcone desmethylxanthohumol (1) and their dimers were synthesized from the commercially available 1-(2,4,6-trihydroxyphenyl)ethan-1-one in five and six linear steps, respectively. The structures of the eight new derivatives were confirmed using(1)H NMR, (13)C NMR and HRMS. The antioxidant activity of the new chalcone derivatives were evaluated in a PC12 cell model of H2O2-induced oxidative damage. The SAR studies suggested that the catechol motif was essential for the antioxidant activity...
September 13, 2016: European Journal of Medicinal Chemistry
Naonobu Tanaka, Yuki Yano, Yutaka Tatano, Yoshiki Kashiwada
Two novel prenylated benzophenone related meroterpenes, hypatulins A (1) and B (2), were isolated from the leaves of Hypericum patulum. The structures of 1 and 2 were assigned by spectroscopic analysis, chemical conversion, and calculations of the ECD (electron circular dichroism) spectra. Hypatulin A (1) had a unique densely substituted tricyclic octahydro-1,5-methanopentalene core, while hypatulin B (2) possessed a bicyclo[3.2.1]octane moiety. Hypatulin A (1) exhibited antimicrobacterial activity against Bacillus subtilis...
October 21, 2016: Organic Letters
Rita Hairani, Rachsawan Mongkol, Warinthorn Chavasiri
Four natural 1,2-naphthoquinones: mansonones C, E, G, and H were isolated from the dichloromethane extract of Mansonia gagei Drumm. heartwoods. Mansonone G was further converted to eight ether and four ester analogues. The structures of mansonones and the analogues were well-confirmed by spectroscopic techniques. All compounds were evaluated for their antibacterial activity against Gram-positive and negative bacteria. Further modification of mansonone G furnished certain analogues displaying better activity than natural mansonones...
September 17, 2016: Bioorganic & Medicinal Chemistry Letters
Francesco Foschi, Torsten Roth, Hubert Wadepohl, Lutz H Gade
Double addition of Grignard reagents to isonitriles was achieved in the presence of stoichiometric amounts of [Ti(OiPr)4]. Functionalized isonitrile components were obtained in situ via lithiation of chiral and achiral 2-oxazolines, and the resulting amidomethyltitanium intermediate further reacted with a range of electrophiles. The established multicomponent procedure gave rise to highly substituted 2-aminomorpholines, acyclic diamino alcohols, and prenylated amino alcohols via straightforward synthetic protocols...
October 7, 2016: Organic Letters
Kok-Yong Chin, Kok-Lun Pang, Ima-Nirwana Soelaiman
Tocotrienol is a member of vitamin E family and is well-known for its antioxidant and anti-inflammatory properties. It is also a suppressor of mevalonate pathway responsible for cholesterol and prenylated protein synthesis. This review aimed to discuss the health beneficial effects of tocotrienol, specifically in preventing or treating hyperlipidaemia, diabetes mellitus, osteoporosis and cancer with respect to these properties. Evidence from in vitro, in vivo and human studies has been examined. It is revealed that tocotrienol shows promising effects in preventing or treating the health conditions previously mentioned in in vivo and in vitro models...
2016: Advances in Experimental Medicine and Biology
Loiy Elsir A Hassan, Muhammad Adnan Iqbal, Saad S Dahham, Yasser M Tabana, Mohamed B Khadeer Ahamed, Amin M S Abdul Majid
Cancer is characterized by uncontrolled cell division caused by dysregulation of cell proliferation. Therefore, agents that impair cancer cell proliferation could have potential therapeutic value. Higher plants are considered to be a good source of anticancer agents, and several clinically tested chemotherapeutic agents have been isolated from plants or derived from constituents of plant origin. In the present study, a prenylated flavone (isoglabratephrin) was isolated from aerial parts of Tephrosia apollinea using a bioassay-guided technique...
September 26, 2016: Anti-cancer Agents in Medicinal Chemistry
Liqin Ye, Chunxiang Yang, Weidong Li, Jiangbo Hao, Meng Sun, Jingru Zhang, Zhongshuang Zhang
The types and amounts of volatiles in denucleated fruit of 30 Chinese dwarf cherry germplasms were determined by headspace solid-phase microextraction and gas chromatography-mass spectrometry to assess the genotypic variation. Eighty-five volatiles were identified; hexyl acetate, 4-penten-1-yl acetate, prenyl acetate, (Z)-pent-2-enyl hexanoate, geranyl acetate, n-butyl acetate, (3Z)-3,7-dimethylocta-1,3,6-triene, geraniol, pent-2-enyl butanoate, ethyl caprylate, butyl hexanoate, and linalool were the main volatiles...
February 15, 2017: Food Chemistry
Wei Wang, Yu-Ying Zhao, Hubiao Chen, Qing-Ying Zhang, Hong Liang
Chemical investigation on the ethyl acetate extract of the roots of Hedysarum multijugum resulted in the isolation of two new prenylated isoflavonoids: 5, 7, 2'-trihydroxy-4'-methoxy-3'-(γ, γ-dimethylallyl) isoflavone (hedysarimisoflavone A, 1) and 5, 7, 2'-trihydroxy-4'-methoxy-6, 8-di-(γ, γ-dimethylallyl) isoflavone (hedysarimisoflavone B, 2). Their structures were elucidated on the basis of spectroscopic analyses, especially, (1)H and (13)C NMR spectra in conjunction with their 2D experiments, (1)H-(1)H COSY, HMQC, HMBC, and NOESY...
September 23, 2016: Journal of Asian Natural Products Research
Hisataka Sabe, Ari Hashimoto, Shigeru Hashimoto, Tsukasa Oikawa
The mevalonate pathway results in the prenylation of small GTPases, which are pivotal for oncogenesis and cancer malignancies. However, inhibitors of this pathway, such as statins, have not necessarily produced favorable results in clinical trials. We recently identified properties of statin responders, together with the underlying molecular mechanisms and simple biomarkers to predict these responders.
July 2016: Molecular & Cellular Oncology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"