1,095 research outputs found
Structural characterization of highly glucosylated crocins and regulation of their biosynthesis during flower development in Crocus
Crocin biosynthesis in Crocus has been proposed to proceed through a zeaxanthin cleavage pathway catalyzed by carotenoid cleavage dioxygenase 2 (CCD2), and followed by glucosylation reactions catalyzed by CsGT2 (UGT74AD1). In Crocus ancyrensis flowers, crocins with eight (crocin-1), seven (crocin-2), and six glucose (crocin-3) moieties accumulated both in stigma and tepals. We have characterized the structure of these highly glucosylated crocins and follow up their accumulation by high-resolution liquid chromatography coupled with diode array detector along the development of both tissues, and coupled to the isolation and analysis of the expression of eighteen genes (PSY-I, PSY-II, PDS-(I-V), ISO-ZDS, ZDS, CtrISO, LYC-I and II, BCH, CaCCD2, UGT74AD2-5) related with the apocarotenoid metabolism in C. ancyrensis tepals and stigmas. Structure elucidation of crocin-1 and crocin-2 was done by the combined use of 1D and 2D [H, H] (gCOSY and TOCSY and ROESY) and [H-C] NMR experiments, revealing that for crocin-1 was all-trans-crocetin O-[β-D- Glucopyranosyl)-(1→4)-(β-D-glucopyranosyl)-(1→2)]-O-[β-D-glucopyranosyl-(1→6)]-β-D-glucopyranosyl diester, while crocin-2 showed an identical structure except for the absence of one glucose residue in one end of the molecule. Crocins accumulation was not synchronically regulated in stigma and tepals, although in both cases crocins accumulation parallels tissue development, decreasing at anthesis. The expression of the carotenogenic genes PSY, ZDS-V, BCH, and LCY-II was correlated with crocins accumulation. In addition, CaCCD2 and only one of the four glucosyltransferase encoding genes, UGT74AD2, were highly expressed, and the expression was correlated with high levels of crocins accumulation in stigma and tepals.This work was supported by the Spanish Ministerio de Economía y Competitividad (BIO2013-44239-R) and participates in the IBERCAROT network (112RT0445). OA was funded by FPCYTCLM through the INCRECYT Programme.Peer Reviewe
One-Pot Synthesis of Polycyclic Nucleosides with Unusual Molecular Skeletons
An R hydroxy pyrrolidine tricyclic nucleoside 3 and its spontaneous reaction with acetone is
described. In this transformation highly functionalized polycyclic nucleosides with rather unusual
molecular skeletons are formed in a complete regio-and stereoselective way. The reaction involves
the formation of three new bonds, two of them novel carbon-carbon bonds, in a one-pot way. An
enamine-iminium mechanism with participation of carbinolamine, iminium ion, and enamine
intermediates is proposed as a plausible explanation for this transformation. The scope of the
reaction is briefly studied concluding that the nature of the ketone (R1COR2) is critical for the initial
attack of the NH to the carbonyl group.We thank Susana Ruiz for excellent
technical assistance. The Spanish MEC/MCINN (project
SAF 2006-12713-C02-01) and the Comunidad de Madrid
(project BIPEDD-CM S-B10-0214-2006) are also acknowl-
edged for financial support. The Spanish Consejo Superior
de Investigaciones Cientı´ ficas is also acknowledged for a
JAE-Doc contract to M.-C.B.Peer reviewe
Synthesis, biological evaluation, and molecular modeling of nitrile-containing compounds : exploring multiple activities as anti-Alzheimer agents
Funding: EC COST Actions D34 and CM1103 for Short-term Scientific Mission funding (EM, DS, MM); the School of Biology at the University of St. Andrews (EJS, RRR); the Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa (AN, ACJ, TR, MCC); FCT, the Portuguese Foundation for Science and Technology (Project PTDC/SAU-NEU/64151/2006 (MCC), and project grant (DS) Vega 2/0127/18 and the contract No. APVV-15-0455 of Slovak Research and Development Agency (MM).Based on the monoamine oxidase (MAO) inhibition properties of aminoheterocycles with a carbonitrile group we have carried out a systematic exploration to discover new classes of carbonitriles endowed with dual MAO and AChE inhibitory activities, and Aβ anti‐aggregating properties. Eighty‐three nitrile‐containing compounds, 13 of which are new, were synthesized and evaluated. in vitro screening revealed that 31 , a new compound, presented the best lead for trifunctional inhibition against MAO A (0.34 μM), MAO B (0.26 μM), and AChE (52 μM), while 32 exhibited a lead for selective MAO A (0.12 μM) inhibition coupled to AChE (48 μM) inhibition. Computational analysis revealed that the malononitrile group can find an advantageous position with the aromatic cleft and FAD of MAO A or MAO B. However, the total binding energy can be handicapped by an internal penalty caused by twisting of the ligand molecule and subsequent disruption of the conjugation ( 32 in MAO B compared to the conjugated 31 ). Conjugation is also important for AChE as well as the hydrophilic character of malononitrile that allows this group to be in close contact with the aqueous environment as seen for 83 . Although the effect of 31 and 32 against Aβ1–42, was very weak, the effect of 63 and 65 , and of the new compound 75 , indicated that these compounds were able to disaggregate Aβ1–42 fibrils. The most effective was 63 , a (phenylhydrazinylidene)propanedinitrile derivative that also inhibited MAO A (1.65 μM), making it a potential lead for Alzheimer's disease application.PostprintPeer reviewe
A Spectroscopic study of colchicine in the solid state and in solution by multinuclear magnetic resonance and vibrational circular dichroism
Although almost 200-years-old, several unknown aspects remain to be explored of colchicine, the unique available drug for acute flares of gout. In this article, we report density-functional theory (DFT) studies of geometry, energy, and NMR; 1H-, 13C-, and 15N-NMR chemical shifts and some spin-spin coupling constants, including the complete analysis of the saturated part (ring B); the assignment of both enantiomers by NMR using a chiral solvating agent; solid-state NMR experiments of the different forms of natural and racemic colchicine, and IR and vibrational circular dichroism (VCD) studies of these same forms. Copyright © 2014 Verlag Helvetica Chimica Acta AG, Zürich.Peer Reviewe
Efficient multi-click approach to well-defined two-faced octasilsesquioxanes: the first perfect Janus nanocube
The preparation of the first structurally well-defined Janus nanocube
showing two chemically distinct opposed faces is described.
The synthetic approach is based on a highly efficient and symmetrycontrolled
CuAAC functionalization of an octa-azido cubic silsesquioxane
with a conformationally constrained tetra-alkyne with an
appropriate spatial orientation of the triple bonds.with two sets of orthogonally reactive functional groups.
We gratefully acknowledge financial support by the Spanish
Ministerio de Ciencia e Innovación (project MAT2010-20646-
C04-03) and Ministerio de Economía y Competitividad (project
MAT2014-51937-C3-1-P). We also acknowledge the Spanish
Ministerio de Economía y Competitividad for a FPI contract
to A. B., and CSIC for a JAEDOC contract to J. R. S. and a JAEPRE
contract to M. E. P.-O., and for support of the publication fee by
the CSIC Open Access Publication Support Initiative through its
Unit of Information Resources for Research (URICI).Peer reviewe
Bifidobacterial ß-galactosidase-mediated production of galacto-oligosaccharides: structural and preliminary functional assessments
This work was sponsored by FrieslandCampina. DS, VA, and
FB are members of APC Microbiome Ireland, which is a
research center funded by Science Foundation Ireland (SFI),
through the Irish Government’s National Development Plan.
The authors and their work were supported by SFI (Grant
SFI/12/RC/2273), FEMS Research Grant FEMS-RG-2016-0103
and project AGL2017-84614-C2-1-R funded by the Spanish
Ministry of Economy, Industry and Competitiveness. OH-H
has received funding from the European Union’s Horizon 2020
Research and Innovation Program under the Marie Skłodowska-
Curie grant agreement no. 843950
Antivascular and antitumor properties of the tubulin-binding chalcone TUB091
We investigated the microtubule-destabilizing, vascular-targeting, anti-tumor
and anti-metastatic activities of a new series of chalcones, whose prototype compound
is (E)-3-(3’’-amino-4’’-methoxyphenyl)-1-(5’-methoxy-3’,4’-methylendioxyphenyl)-
2-methylprop-2-en-1-one (TUB091). X-ray crystallography showed that these
chalcones bind to the colchicine site of tubulin and therefore prevent the curved-tostraight
structural transition of tubulin, which is required for microtubule formation.
Accordingly, TUB091 inhibited cancer and endothelial cell growth, induced G2/M
phase arrest and apoptosis at 1-10 nM. In addition, TUB091 displayed vascular
disrupting effects in vitro and in the chicken chorioallantoic membrane (CAM) assay
at low nanomolar concentrations. A water-soluble L-Lys-L-Pro derivative of TUB091
(i.e. TUB099) showed potent antitumor activity in melanoma and breast cancer
xenograft models by causing rapid intratumoral vascular shutdown and massive
tumor necrosis. TUB099 also displayed anti-metastatic activity similar to that of
combretastatin A4-phosphate. Our data indicate that this novel class of chalcones
represents interesting lead molecules for the design of vascular disrupting agents
(VDAs). Moreover, we provide evidence that our prodrug approach may be valuable
for the development of anti-cancer drugs.M-DC thanks the Fondo Social Europeo (FSE) and
the JAE Predoc Programme for a predoctoral fellowship.
This work has received the Ramón Madroñero award for
young researchers (to M-DC and OB) in the XVII call
www.impactjournals.com/oncotarget 17 Oncotarget
sponsored by the Spanish Society of Medicinal Chemistry
(SEQT). This project has been supported by the Spanish
Ministerio de Economia y Competitividad (SAF2012-
39760-C02-01 to M-JC, M-JP-P, SV and E-MP; and
BIO2013-42984-R to JFD), Comunidad de Madrid
(BIPEDD2; ref. P2010/BMD-2457 to M-JC and J-FD),
the Swiss National Science Foundation (310030B_138659
and 31003A_166608; to MOS). The authors acknowledge
networking contribution by the COST Action CM1407
“Challenging organic syntheses inspired by nature - from
natural products chemistry to drug discovery” and COST
action CM1470.Peer reviewe
CIBERER : Spanish national network for research on rare diseases: A highly productive collaborative initiative
Altres ajuts: Instituto de Salud Carlos III (ISCIII); Ministerio de Ciencia e Innovación.CIBER (Center for Biomedical Network Research; Centro de Investigación Biomédica En Red) is a public national consortium created in 2006 under the umbrella of the Spanish National Institute of Health Carlos III (ISCIII). This innovative research structure comprises 11 different specific areas dedicated to the main public health priorities in the National Health System. CIBERER, the thematic area of CIBER focused on rare diseases (RDs) currently consists of 75 research groups belonging to universities, research centers, and hospitals of the entire country. CIBERER's mission is to be a center prioritizing and favoring collaboration and cooperation between biomedical and clinical research groups, with special emphasis on the aspects of genetic, molecular, biochemical, and cellular research of RDs. This research is the basis for providing new tools for the diagnosis and therapy of low-prevalence diseases, in line with the International Rare Diseases Research Consortium (IRDiRC) objectives, thus favoring translational research between the scientific environment of the laboratory and the clinical setting of health centers. In this article, we intend to review CIBERER's 15-year journey and summarize the main results obtained in terms of internationalization, scientific production, contributions toward the discovery of new therapies and novel genes associated to diseases, cooperation with patients' associations and many other topics related to RD research
Alignment of the CMS silicon tracker during commissioning with cosmic rays
This is the Pre-print version of the Article. The official published version of the Paper can be accessed from the link below - Copyright @ 2010 IOPThe CMS silicon tracker, consisting of 1440 silicon pixel and 15 148 silicon strip detector modules, has been aligned using more than three million cosmic ray charged particles, with additional information from optical surveys. The positions of the modules were determined with respect to cosmic ray trajectories to an average precision of 3–4 microns RMS in the barrel and 3–14 microns RMS in the endcap in the most sensitive coordinate. The results have been validated by several studies, including laser beam cross-checks, track fit self-consistency, track residuals in overlapping module regions, and track parameter resolution, and are compared with predictions obtained from simulation. Correlated systematic effects have been investigated. The track parameter resolutions obtained with this alignment are close to the design performance.This work is supported by FMSR (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ,
and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS
(Colombia); MSES (Croatia); RPF (Cyprus); Academy of Sciences and NICPB (Estonia);
Academy of Finland, ME, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG,
and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF (Korea); LAS (Lithuania); CINVESTAV, CONACYT,
SEP, and UASLP-FAI (Mexico); PAEC (Pakistan); SCSR (Poland); FCT (Portugal); JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); MST and MAE (Russia); MSTDS (Serbia); MICINN and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); TUBITAK and TAEK (Turkey); STFC (United Kingdom); DOE and NSF (USA)