Search results for "Selectivity"
showing 10 items of 1148 documents
Catalytic Asymmetric Formal [3+2] Cycloaddition of 2-Isocyanatomalonate Esters and Unsaturated Imines: Synthesis of Highly Substituted Chiral γ-Lacta…
2017
[EN] Unlike their isocyano and isothiocyanato analogues, isocyanato esters remain almost unexplored as formal 1,3-dipoles in asymmetric catalytic reactions. The first asymmetric formal [3+2] cycloaddition involving isocyanato esters and electrophilic alkenes is reported. Diisopropyl 2-isocyanatomalonate reacts with a,b-unsaturated N-(o-anisidyl) imines in the presence of a Mg(OTf)2¿BOX complex to give highly substituted chiral pyrrolidinones featuring a conjugate exocyclic double bond with excellent yields and enantiomeric excesses up to 99%. Several transformations of the resulting heterocycles, including the synthesis of a pyroglutamic acid derivative, have been carried out.
A Colorimetric Membrane-Based Sensor with Improved Selectivity towards Amphetamine
2021
Due to their simplicity, speed and low cost, chemical spot tests are increasingly demanded for the presumptive identification of illicit drugs in a variety of contexts such as point-of-care assistance or prosecution of drug trafficking. However, most of the colorimetric reactions used in these tests are, at best, drug class selective. Therefore, the development of tests based on chemical reactions with improved discrimination power is of great interest. In this work, we propose a new colorimetric assay for amphetamine (AMP) based on its reaction with solutions of alkaline gold bromide to form an insoluble yellow–orange derivative. The resulting suspensions are then filtered onto nylon membr…
X-ray crystallography-promoted drug design of carbonic anhydrase inhibitors.
2015
1-N-Alkylated-6-sulfamoyl saccharin derivatives were prepared and assayed as carbonic anhydrase inhibitors (CAIs). During X-ray crystallographic experiments an unexpected hydrolysis of the isothiazole ring was evidenced which allowed us to prepare highly potent enzyme inhibitors with selectivity for some isoforms with medical applications.
Microseparation techniques for the study of the enantioselectivity of drug-plasma protein binding.
2009
Stereoselectivity in protein binding can have a significant effect on the pharmacokinetic and pharmacodynamic properties of chiral drugs. The investigation of enantioselectivity of drugs in their binding with human plasma proteins and the identification of the molecular mechanisms involved in the stereodiscrimination by the proteins represent a great challenge for clinical pharmacology. In this review, the separation techniques used for enantioselective protein binding experiments are described and compared. An overview of studies on enantiomer–protein interactions, enantiomer–enantiomer interactions as well as chiral drug–drug interactions, including allosteric effects, is presented. The c…
Relevancia clínica de la selectividad de los inhibidores del cotransportador sodio-glucosa tipo 2
2016
Selectivity is the property of a drug to preferentially bind to a biological structure. Most drugs can bind and stimulate or inhibit more than one system. Therefore, it is important that they are selective for the intended site and that the doses used do not have effects on other sites, which could provoke adverse reactions. Selectivity is assessed through in vitro experiments on organs or isolated cells. If the aim is to compare drugs, the experiment should be conducted in the same tissue and with the same design. Even so, the results cannot be directly extrapolated to clinical practice due to the influence of pharmacokinetic properties, which allow an adequate dose of the drug to reach th…
Parental working time patterns and children's socioemotional wellbeing: Comparing working parents in Finland, the United Kingdom, and the Netherlands
2017
Abstract This cross-national study examined the connections between parental working time patterns (i.e., regular day work vs. nonstandard working hours) and children's socio-emotional wellbeing defined in terms of internalizing and externalizing problems and prosocial behavior. We also examined how the total number of hours worked, changes in work schedules, working overtime at short notice, and having an influence over one's work schedules were linked with children's wellbeing. Data were collected by a web survey from Finnish ( n = 358), Dutch ( n = 200) and British ( n = 267) parents with children aged 3 to 12 years. The results showed, that in all three countries parents working nons…
Intervention Programs to Promote the Quality of Caregiver–Child Interactions in Childcare: A Systematic Literature Review
2021
Sensitive caregiver–child interactions appear fundamental throughout childhood, supporting infants’ wellbeing and development not only in a familial context but in professional caregiving as well. The main aim of this review was to examine the existing literature about Early Childhood Education Context (ECEC) intervention studies dedicated to caregiver–child interaction, fostering children’s socioemotional developmental pathways. Studies published between January 2007 and July 2021 were identified in four electronic databases following PRIMSA guidelines. The initial search yielded a total of 342 records. Among them, 48 studies were fully reviewed. Finally, 18 of them met all inclusion crite…
Selectivity of clientele in Finnish private early childhood education and care
2021
In accordance with the Nordic welfare model, the Finnish early childhood education and care (ECEC) system has traditionally been based on public provision and the idea of universalism. However, over the last twenty years the ECEC system has undergone market-oriented reforms. As a result, the share of private for-profit ECEC provision has grown significantly. By applying impression management theory, this qualitative research examines how representatives of private ECEC providers describe the selection and selectivity of their clientele and how they aim at managing the impression they convey through their descriptions. The study shows how three different mechanisms of selectivity are produce…
Three- to four-year-old children’s socioemotional competencies assessed by kindergarten teachers in general and physical education settings, and by p…
2014
Summary. Early childhood education programs represent a valuable early learning opportunity for promoting the socioemotional skills. The aims of the study were to validate the socioemotional skills observation scale, to compare 3-4 year-old children’s socioemotional competencies in general kindergarten settings and in a PE session, separately by gender, and to compare 3-4 year-old children’s socioemotional competencies in general kindergarten settings and at home. The participants were 59 children (23 girls, 36 boys) from six communal kindergartens in Finland, their parents, and early educators. The data were analyzed using the confirmatory factor analysis and t-tests. The results showed th…
Financial wealth, socioemotional wealth, and founder exits: an empirical examination of Chinese IPOs
2021
Initial public offerings (IPOs) are typically viewed as the peak of entrepreneurial success, providing founder-CEOs a chance to profitably exit. Founder-CEOs, however, are often motivated by non-financial considerations in addition to the desire to amass wealth. According to the behavioral agency model, the founder-CEOs’ framing of gains vs. losses of their wealth creation at IPO determines their risk aversion vs. risk taking behaviors. In addition, the behavioral agency model argues that founder-CEOs with a great deal of socioemotional wealth fear losing that wealth. This fear will attenuate their aversion to losing financial wealth. To test our model, we collected a sample of 130 entrepre…