Gold(I) forms neutral complexes with binol phosphates that are unreactive in the catalytic cyclisation of enynes. Reaction in protic solvents or activation by silver(I) restores the catalytic activity.
The compound [Ru3(mu-H)(mu3-eta2-ampy)(CO)9] (1; Hampy =2-amino-6-methylpyridine) reacts with diynes RC4R in THF at reflux temperature to give the ynenyl derivatives [Ru3(mu3-eta2-ampy)(mu-eta3-RC...CC-CHR)(mu-CO)2-(CO)6] (2: R=CH2OPh; 3: R=Ph). These products contain a 1,4-disubstituted butynen-3-yl ligand attached to two ruthenium atoms. The compound [Ru3(mu-eta2-ampy)[mu3-eta6-PhCC5(C...CPh)-HPh2](CO)7] (4), which contains an eta5-cyclopentadienyl ring and a bridging carbene fragment, has also been obtained from the reaction of 1 with diphenylbutadiyne. This compound arises from a remarkable [3+2] cycloaddition reaction of a preformed 1,4-diphenylbutynen-4-yl ligand with a triple bond of a second diphenylbutadiyne molecule. The reactivity of the ynenyl derivatives 2 and 3 with diynes and alkynes has been studied. In all cases, compounds of the general formula [Ru3(mu-eta2-ampy)[mu3-eta5-C(=CHR)C=CRCR1=CR2](CO)7] (5-17) have been obtained. They all contain a ruthenacyclopentadienyl fragment formed by coupling of the coordinated ynenyl ligand of 2 (R = CH2OPh) or 3 (R = Ph) with a triple bond of the new reagent (the CR1=CR2 fragment results from the incoming diyne or alkyne reagent). While most of the products derived from 2 have the alkenyl C=CHR fragment with a Z configuration (R cis to Ru), all the compounds obtained from 3 have this fragment with an E configuration. Except 2 and 3, all the cluster complexes described in this article have a five-electron donor ampy ligand attached to only two metal atoms, a coordination mode unprecedented in cluster chemistry.
The objective of the study was to assess the cost of multiple sclerosis (MS) patients in Argentina categorized by disease severity using a societal perspective. Method: Cross-sectional study including MS patients from 21 MS centers in 12 cities of Argentina. Patients were stratified by disease severity using the expanded disability status scale (EDSS) (group 1 with EDSS score between 0 and 3; group 2 with EDSS .3 and ,7; group 3 with EDSS $7). Direct and indirect costs were analyzed for the second quarter of 2012 from public sources and converted to US Dollars. Results: 266 patients were included. Mean annual cost per MS patient was USD 36,025 (95%CI 31,985-38,068) forts patients with an EDSS between 0-3; USD 40,705 (95%CI 37,300) for patients with EDSS .3 and ,7, and USD 50,712 (95%CI 47,825-62,104) for patients with EDSS $7. Conclusions: This is the first Argentine study evaluating the costs of MS considering disease severity.Keywords: multiple sclerosis, costs, cost-of-illness, Argentina, Latin America. RESUMOEl objetivo del estudio fue evaluar el costo de los pacientes con esclerosis múltiple (EM) en Argentina categorizados por severidad de la enfermedad. Método: Estudio de corte transversal que incluyó pacientes con EM en 12 ciudades de Argentina. Los pacientes se estratificaron según expanded disability status scale (EDSS) (grupo 1 EDSS entre 0 y 3; grupo 2 EDDS .3 y ,7; grupo 3 EDSS $7). Los costos directos e indirectos fueron analizados para el segundo trimestre de 2012 y convertidos a dólares estadounidenses. Resultados: 266 pacientes fueron incluidos. El coste medio anual por paciente con EM fue de USD 36,025 (31,985-38,068 IC95%) para los pacientes con un EDSS entre 0-3; USD 40,705 (37,,300 IC95%) para los pacientes con EDSS .3 y ,7 y USD 50,712 (47,825-62,104 IC95%) para los pacientes con EDSS $7. Conclusiones: Primer estudio argentino evaluar los costes de la EM considerado la gravedad de la enfermedad.Palavras-chave: esclerosis múltiple, costos, enfermedad, Argentina, Latino-América.
An overview of the synthesis and applications of chiral 2,3-epoxy alcohols containing unsaturated chains is presented. One of the fundamental synthetic routes to these compounds is Sharpless asymmetric epoxidation, which is reliable, highly chemoselective and enables easy prediction of the product enantioselectivity. Thus, unsaturated epoxy alcohols are readily obtained by selective oxidation of the allylic double bond in the presence of other carbon-carbon double or triple bonds. The wide availability of epoxy alcohols with unsaturated chains, the versatility of the epoxy alcohol functionality (e.g. regio- and stereo-selective ring opening; oxidation; and reduction), and the arsenal of established alkene chemistries, make unsaturated epoxy alcohols powerful starting materials for the synthesis of complex targets such as biologically active molecules. The popularization of ring-closing metathesis has further increased their value, making them excellent precursors to cyclic compounds.
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