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Oxidation of aminodiols mediated by homogeneous and heterogeneous TEMPO
2004
The conversion of amino diols to aminohy- droxy acids by oxidation of the primary hydroxy group mediated by homogeneous and heterogeneous TEMPO (2,2,6,6-tetramethylpiperidine 1-oxyl radi- cal) is reported. The synthesis uses NaOCl as primary oxidant and TEMPO, either dissolved in the homoge- neous phase or entrapped in a sol-gel matrix, as cata- lytic mediator. Homogeneous TEMPO is suitable for the oxidation of aliphatic methylamino diols, while the hybrid organic-inorganic silica sol-gel catalysts are more selective mediators for the oxidation of ben- zylic amino diols like the potent antibiotic chloram- phenicol which, under homogeneous conditions, are unselectively oxidized to benzoic ac…
Prediction of properties of chiral compounds by molecular topology
1998
Abstract A common assumption in chemistry is that chiral behavior is associated with 3-D geometry. However, chiral information is related to symmetry, which allows the topological handling of chiral atoms by weighted graphs and the calculation of new descriptors that give a weight to the corresponding entry in the main diagonal of the topological matrix. In this study, it is demonstrated that, operating in this way, chiral topological indices are obtained that can differentiate the pharmacological activity between pairs of enantiomers. The 50% inhibitory concentration (IC50) values of the D2 dopamine receptor and the σ receptor for a group of 3-hydroxy phenyl piperidines are specifically pr…
3,4′,5,5′-Tetramethoxy-2′-methylbiphenyl-4-ol
2019
The asymmetric unit of the title compound, C17H20O5, contains two independent molecules, A and B, with similar geometries [dihedral angles between the phenyl rings = 56.19 (8) and 54.98 (7)°, respectively]. Intramolecular O—H...O hydrogen bonds occur in both molecules. In the crystal, the A molecules form [1\overline{1}0] chains linked by O—H...O hydrogen bonds from the hydroxyl group to one of the methoxy O atoms. The B molecules form O—H...O hydrogen bonds to the hydroxyl O atoms of the A molecules and thus act as fixed spacers between the chains of molecule A. Some weak C—H...O contacts are also present.
Reaction of 2-acetyltetralone with some esters of benzoic acid
1986
In order to investigate the pharmacological screening of a number of pyran-4-ones their synthesis by cyclization with sulphuric acid of the corresponding 1,3,5-triketones has been carried out with high yields. In the course of preparation of the latter the reaction of 2-acetyltetralone with some esters of benzoic acid derivatives has been studied and in particular, for a number of them, an interesting nucleophilic substitution of a chlorine atom with an alkoxy group on a benzenic nucleus has been evidenced.
ChemInform Abstract: Reaction of 2-Acetyltetralone with Some Esters of Benzoic Acid.
1987
In order to investigate the pharmacological screening of a number of pyran-4-ones their synthesis by cyclization with sulphuric acid of the corresponding 1,3,5-triketones has been carried out with high yields. In the course of preparation of the latter the reaction of 2-acetyltetralone with some esters of benzoic acid derivatives has been studied and in particular, for a number of them, an interesting nucleophilic substitution of a chlorine atom with an alkoxy group on a benzenic nucleus has been evidenced.
Crystal structure of hydrocortisone 17-butyrate
2014
In the title compound, C25H36O6, the two central cyclohexane rings exhibit a chair conformation. The terminal cyclohexene and cyclopentane rings are in half-chair and envelope conformations (with the C atom bearing the methyl substituent as the flap), respectively. The methyl group of the butyrate chain is disordered over two orientations, with a refined occupancy ratio of 0.742 (6):0.258 (6). Intramolecular O—H...O and C—H...O hydrogen bonds are observed. In the crystal, molecules are linked by O—H...O hydrogen bonds into chains running parallel to theaaxis.
Study of the role of sulfur functionalities in humic acids for uranium(VI) complexation
2009
Humic substances influence the speciation and migration behavior of toxic and radiotoxic metal ions, such as actinides, in the environment. Depending on their origin, humic substances contain different amounts of sulfur ranging from 0.1 to 3.6% and 0.5 to 1.43% in soil and aquatic humic substances, respectively [1]. Reduced, intermediately oxidized and highly oxidized sulfur functionalities occur in humic substances [1]. Although sulfur functionalities occur in small concentrations, they can play an important role in the complexation of selected metal ions. Knowledge about the impact of sulfur functionalities on the metal ion complexation by humic substances and their significance compared …
Acceptance and commitment group therapy for treatment of insomnia
2013
Hyväksymis- ja omistautumisterapiaa on käytetty laajasti erilaisten psyykkisten ongelmien hoidossa, niin aikuisilla kuin lapsilla. Viimeaikaisista tutkimuksista HOT:n periaatteiden soveltamisesta nukkumisongelmien ja unettomuuden hoitoon on saatu lupaavia tuloksia. Tämän tutkimuksen tarkoituksena oli selvittää ryhmämuotoisen Hyväksymis- ja omistautumisterapian vaikutuksia unettomuuden hoidossa. Tutkimukseen osallistuneista 32 henkilöä kuului koeryhmään ja 33 tutkittavaa kontrolliryhmään. Hoito suoritettiin ryhmämuotoisena terapiana, joka sisälsi yhteensä kuusi kertaa, joista ensimmäinen tehtiin yksilöllisellä puhelinhaastattelulla. Loput viisi istuntoa pidettiin säännöllisesti viikoittain. …
Institutional logics and social enterprises: Entry mode choices of foreign hospitals in China
2020
When social enterprises, being defined by their social mission and profitability, internationalize, they need to\ud respond to institutional logics in the host country. By juxtaposing institutional logic and entry mode choice\ud literature, this paper shows how social enterprises accommodate different institutional logics when they enter\ud foreign markets. We collected data on Chinese healthcare reform, governmental policies and their changes, and\ud conducted 36 in-depth interviews and three expert group meetings. By analyzing five non-Chinese hospitals\ud entering China, we show how social enterprises, as hybrid organizations, respond to governmental, commercial,\ud and social institutio…
The Concept of Integrated Profit From Contractual Relationship. The Case of Transactions Between Agricultural Producers’ Groups And Agri-Food Sector
2017
Koncepcja zintegrowanej korzyści umożliwia holistyczną analizę celów realizowanych w ramach kontraktów między rolnikami lub organizacjami producentów rolnych a rynkiem przetwórstwa rolno-spożywczego. Wykorzystanym podejściem była teoria kontraktów. Jako cel główny artykułu przyjęto identyfikację form pionowej koordynacji transakcji między grupami producentów rolnych a rynkiem rolno-spożywczym. Celem szczegółowym było zaś rozpoznanie mechanizmu cenowego w umowach i analiza przy wykorzystaniu koncepcji zintegrowanej korzyści (rozważania zawężono do obszaru koordynacji). Przedmiotem badań były kontrakty podpisane w 2014 roku między grupami producentów działającymi na rynku drobiu a pierwszym o…