Publications by authors named "Carmen Puerta"

Background: Previous analyses of excess mortality in drug users compared with the general population have almost always been based on mortality ratios, reporting much higher figures in women than men. This study tests the hypothesis that being a heroin or cocaine user adds more death risk in women than men in Spain.

Methods: A retrospective cohort of 15,305 heroin users (HUs) and 11,905 cocaine users (CUs) aged 15-49 starting drug treatment in 1997-2007 was recruited in Spain and followed until December 2008 to determine vital status and cause of death.

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New indenyl nickel(ii) complexes bearing arsine or stibine ligands synthesised by a new methodology exhibit very high catalytic activities for the oligomerisation of styrene.

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Two conformational polymorphs of novel 2-[2-(3-cyano-4,6-dimethyl-2-oxo-2H-pyridin-1-yl)-ethoxy]-4,6-dimethyl nicotinonitrile have been developed. The crystal structure of both polymorphs (1a and 1b) seems to be stabilized by weak interactions. A difference was observed in the packing of both polymorphs.

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The complex [Cp*RuCl((i)Pr2PNHPy)] (1) reacts with 1-alkynes HC≡CR (R = COOMe, C6H4CF3) in dichloromethane furnishing the corresponding vinylidene complexes [Cp*Ru═C═CHR((i)Pr2PNHPy)]Cl (R = COOMe (2a-Cl), C6H4CF3 (2b-Cl)), whereas reaction of 1 with NaBPh4 in MeOH followed by addition of HC≡CR (R = COOMe, C6H4CF3) yields the metastable π-alkyne complexes [Cp*Ru(η(2)-HC≡CR)((i)Pr2PNHPy)][BPh4] (R = COOMe (3a-BPh4), C6H4CF3 (3b-BPh4)). The transformation of 3a-BPh4/3b-BPh4 into their respective vinylidene isomers in dichloromethane is very slow and requires hours to its completion. However, this process is accelerated by addition of LiCl in methanol solution.

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Ruthenium(II) hydrotris(pyrazolyl)borate chloro complexes bearing picolyl-functionalized N-heterocyclic carbenes [TpRu(κ(2)-C,N-picolyl-(R)I)Cl] (picolyl-(Me)I = 3-methyl-1-(2-picolyl)imidazol-2-ylidene) (1a), picolyl-(iPr)I = 3-isopropyl-1-(2-picolyl)imidazol-2-ylidene (1b), picolyl-(Me)45DClI = 3-methyl-1-(2-picolyl)-4,5-dichloroimidazol-2-ylidene (1c), picolyl-(Ph)I = 3-phenyl-1-(2-picolyl)imidazol-2-ylidene (1d), picolyl-(Me)BI = 3-methyl-1-(2-picolyl)benzoimidazol-2-ylidene (1e)) have been synthesized and characterized. Furthermore, cationic carbonyl derivatives 2a-e have been prepared, characterized, and used to study the donor properties of the picolylcarbene ligands (picolyl-(R)I) via infrared spectroscopy. Also, the reactivity of the 16-electron species [TpRu(κ(2)-C,N-picolyl-(R)I)](+), in situ generated using NaBAr(F)4 (Ar(F) = 3,5-bis(trifluoromethyl)phenyl) as a halide scavenger, toward N2, CH3CN, H2, CH2CH2, S8, and O2 was studied indicating a strong influence of the NHC wingtip and backbone substituents in the product distribution.

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The complexes [Cp*RuCl((i)Pr(2)PSX)] (X = pyridyl, quinolyl) react directly with alcohols ROH (R = Me, Et, (i)Pr, (n)Pr) and NaBPh(4), affording the novel cationic hydrido(alkoxo) derivatives [Cp*RuH(OR)((i)Pr(2)PSX)][BPh(4)]. These ruthenium(IV) compounds result from the formal oxidative addition of the alcohol to the 16-electron fragment {[Cp*Ru((i)Pr(2)PSX)](+)}, generated in situ upon chloride dissociation. The hydrido(alkoxo) complexes are reversibly deprotonated by a strong base such as KOBu(t), yielding the neutral alkoxides [Cp*Ru(OR)((i)Pr(2)PSX)], which are remarkably stable toward β elimination and do not generate the corresponding hydrides.

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Friedel-Craft acylation at 100 °C of 2,5,9,9-tetramethyl-6,7,8,9-tetrahydro-5H-benzocycloheptene [ar-himachalene], a sesquiterpenic hydrocarbon obtained by catalytic dehydrogenation of α-, β- and γ-himachalenes, produces a mixture of two compounds: (3,5,5,9-tetramethyl-6,7,8,9-tetrahydro-5H-benzocyclohepten-2-yl)-ethanone (2, in 69% yield), with a conserved reactant backbone, and 3, with a different skeleton, in 21% yield. The crystal structure of 3 reveals it to be 1-(8-ethyl-8-hydroperoxy-3,5,5-trimethyl-5,6,7,8-tetrahydronaphthalen-2-yl)-ethanone. In this compound O-H…O bonds form dimers.

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The structure of 1,3-bis(4,6-dimethyl-1H-nicotinonitrile-1-yl)1,3-dioxy propane polymorphs has been characterized by X-ray diffraction, FT-IR, 1H and 13C NMR spectroscopies. The influence of intra and intermolecular weak interactions is thoroughly studied in solid state using single crystal X-ray diffraction and FT-IR. These polymorphs belong to monoclinic space group 'P2(1/n)' and 'P2(1/c)'.

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A recyclable catalyst, Ni(0)-CMC-Na, composed of nickel colloids dispersed in a water soluble bioorganic polymer, sodium carboxymethylcellulose (CMC-Na), was synthesized by a simple procedure from readily available reagents. The catalyst thus obtained is stable and highly active in alkene hydrogenations.

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To characterize those patients with probable adult attention deficit hyperactivity disorder (ADHD) who ask for treatment of cocaine use disorders; to estimate the prevalence of probable adult ADHD among these patients. This is a cross-sectional and multi-center study performed at outpatient resources of 12 addiction treatment centers in Spain. Participants were treatment-seeking primary cocaine abusers recruited consecutively at one center and through convenience sampling at the other centers.

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The trihydride complexes [Cp*RuH(3)(kappa(1)-P-(i)Pr(2)PCH(2)X)] [X = pyridine (Py), 2a; quinoline (Quin), 2b] have been prepared by reaction of the corresponding chloro derivatives [Cp*RuCl(kappa(2)-P,N-(i)Pr(2)PCH(2)X)] [X = Py (1a), Quin (1b)] with NaBH(4) in methanol. Both 2a and 2b exhibit quantum-mechanical exchange coupling. The proton-transfer reactions to 2a and 2b using strong as well as weak proton donors have been experimentally and computationally studied.

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The racemic title compound, C(16)H(17)ClN(2), shows a tetra-hydro-isoquinoline skeleton with a 4-chloro-N-methyl-aniline group linked to the C atom at position 1. The dihedral angle between the benzene rings is 85.82 (4)°.

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The asymmetric unit of the title compound, [RuCl(C(10)H(14))(C(17)H(19)O(2))], contains two diastereomers. In both, the Ru(II) ion has a tetra-hedral coordination, formed by two O atoms of the camphor-derived ligand and the p-cymene and Cl ligands. In the crystal structure, weak inter-molecular C-H⋯Cl inter-actions link the mol-ecules into columns propagated along [010].

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The cationic complexes [Ni(eta(3)-CH(2)C(R)CH(2))(SbPh(3))(3)][BAr'(4)] (R = CH(3), H ; Ar' = 3,5-C(6)H(3)(CF(3))(2)), [Ni(eta(3)-CH(2)C(R)CH(2))(AsPh(3))(2)][BAr'(4)] (R = CH(3), H ), [Ni(eta(3)-CH(2)CHCH(2))(PPh(3))(L)][BAr'(4)] (L = SbPh(3), AsPh(3)), and the neutral derivatives [Ni(eta(3)-CH(2)C(R)CH(2))Br(L)] (L = SbPh(3), R = CH(3), H ; L = AsPh(3), R = CH(3), H ) have been prepared and characterized. The X-ray crystal structures of , , , and have been determined. These complexes are very active catalyst precursors for the low-molecular weight oligomerization of RC(6)H(4)CH[double bond, length as m-dash]CH(2) to mainly dimers and trimers of styrene (R = H) or 4-methylstyrene (R = CH(3)).

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Crystals of the title compound, C(7)H(7)NO(3), under Mo Kα radiation sublime in less than 1h at room temperature. However, it was possible to collect data at 100K. It crystallized as the E isomer only.

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The title compound, C(6)H(5)NO(3), was synthesized via condensation of furfural with nitro-methane in the presence of isobutyl-amine. The compound crystallizes exclusively as the E isomer. The angle between the mean planes of the furan ring and the nitro-alkenyl group is 1.

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The activation of 1,1-diphenyl-2-propyn-1-ol by the metallic fragment [(eta (5)-C 5Me 5)Ru(dippae)] (+) {dippae = 1,2-bis[(diisopropylphosphanyl)amino]ethane}, followed by dehydration, produces a cationic complex that, by deprotonation and rearrangement, leads to a neutral complex with a phosphinoallyl ligand containing a pyrrolidin-2-yl ring.

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Different substituted 3,3'-arylidenebis-4-hydroxycoumarins (1-7) and tetrakis-4-hydroxycoumarin derivative 8 are the final products when 4-hydroxycoumarin and aromatic aldehydes containing different groups in ortho, meta or para positions condense in boiling ethanol or acetic acid. Upon heating 3,3'-arylidenebis-4-hydroxycoumarins, and tetrakis-4-hydroxycoumarin derivative in anhydride acetic acid, the epoxydicoumarins (9-16) were formed. From a study of nuclear magnetic resonance and infrared spectra, intramolecularly hydrogen-bonded structures are proposed for the dicoumarols (1-8).

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The syntheses of the chloro complexes [Ru(eta5-C5R5)Cl(L)] (R = H, Me; L = phosphinoamine ligand) (1a-d) have been carried out by reaction of [(eta5-C5H5)RuCl(PPh3)2] or {(eta5-C5Me5)RuCl}4 with the corresponding phosphinoamine (R,R)-1,2-bis((diisopropylphosphino)amino)cyclohexane), R,R-dippach, or 1,2-bis(((diisopropylphosphino)amino)ethane), dippae. The chloride abstraction reactions from these compounds lead to different products depending on the starting chlorocomplex and the reaction conditions. Under argon atmosphere, chloride abstraction from [(eta5-C5Me5)RuCl(R,R-dippach)] with NaBAr'4 yields the compound [(eta5-C5Me5)Ru(kappa3P,P'-(R,R)-dippach)][BAr'4] (2b) which exhibits a three-membered ring Ru-N-P by a new coordination form of this phosphinoamine.

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The complexes [Ni(eta(3)-CH(2)CHCH(2))Br(kappa(1)P-PR(2)CH(2)CH=CH(2))] (R = Ph 1, (i)Pr2 ) and [Ni(eta(3)-CH(2)C(R')CH(2))(kappa(1)P-PR(2)CH(2)CH=CH(2))(2)][BAr'(4)] (R' = H, R = Ph 4a, R = (i)Pr 4b; R' = CH(3), R = Ph 5a, R = (i)Pr 5b; Ar' = 3,5-C(6)H(3)(CF(3))(2)) have been prepared and characterized. The X-ray crystal structures of 1, 2 and 5b have been determined. 4a-b and 5a-b are catalyst precursors for the oligomerization of RC(6)H(4)CH=CH(2) to oligostyrene (R = H) or oligo(4-methylstyrene) (R = CH(3)) respectively, without the need of a co-catalyst such as methylalumoxane.

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The complexes [(C5R5)RuH(dippae)] [R = H (1a), Me (2a); dippae = 1,2-bis(diisopropylphosphinoamino)ethane] and [(C5R5)RuH((R,R)-dippach)] [R = H (1b), Me (2b); (R,R)-dippach = (R,R)-1,2-bis(diisopropylphosphinoamino)cyclohexane] have been prepared and characterized. The cationic ruthenium(IV) dihydride derivatives [(C5R5)RuH2(dippae)][BPh4] [R = H (3a), Me (4a)] and [(C5R5)RuH2((R,R)-dippach)][BPh4] [R = H (3b), Me (4b)] are also reported. No significant intramolecular interaction between the amino protons and the hydrogen atoms bound to the metal has been observed in any of these compounds.

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Rolipram suppresses experimental autoimmune encephalomyelitis (EAE) and diminishes cell infiltration of the central nervous system (CNS). In Lewis rats with EAE, rolipram reduced matrix metalloproteinase-9 (MMP-9) gene expression in lymph node cells (LNCs) and spinal cord, decreased basal levels of nuclear (p50/p65) NF-kappaB in LNCs from treated rats, and impaired CD3 mediated NF-kappaB translocation. Rolipram reduced the luciferase activity directed by the NF-kappaB binding site of the MMP-9 gene in lymphocytes.

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The pseudotetrahedral, formally 5-coordinate complex [Ni(eta 3-CH2C(CH3)CH2)(SbPh3)3][BAr'4] (Ar' = 3,5-C6H3(CF3)2) as well as the 4-coordinate derivative [Ni(eta 3-CH2C(CH3)CH2)(AsPh3)2][BAr'4] act as extremely efficient catalysts for the oligomerization of styrene.

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The reaction of the chloro-complex [CpRuCl(PEt(3))(2)] with acetylene gas in methanol gave the pi-alkyne complex [CpRu(eta(2)-HCtbd1;CH)(PEt(3))(2)][BPh(4)] (1), which has been structurally characterized by X-ray analysis. The alkyne complex undergoes spontaneous isomerization even at low temperature, yielding the metastable alkynyl-hydride complex [CpRu(H)(Ctbd1;CH)(PEt(3))(2)][BPh(4)] (2), as the result of the oxidative addition of the alkyne C-H bond. This compound has also been structurally characterized despite it tautomerizes spontaneously into the stable primary vinylidene [CpRu(=C=CH(2))(PEt(3))(2)][BPh(4)] (3).

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