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Silver Ion Complexes with Macrocyclic Compounds Build on the Basis of Cyclotriphosphazene Ring

100%

Seliger P. , Andrijewski G. , Siwy M. , Sęk D.

Polish Journal of Chemistry

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2009

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tom Vol. 83, nr 4

581-588

EN

The new diethanethiol-dipyrrolidinyl PNP-lar iat ether, L2, was syn the sized. Spectral properties of the tetrapyrrolidinyl PNP-lar iat ether L1 as well as L2 and their complexes with silver cat ion were investigated. The formation constants of the complexes with Ag+ in methanol solutions were determined. The 1H NMR and potentiometric measurements in dicate that in both cases complexation of Ag+ ions pro ceeds with participation of endocyclic nitrogen atom of cyclophosphazene ring and of polyether oxygen donors. In the case of L2 there is no evidence for stabilization of the ob tained complex by ethanethiol sub units attached to the exocyclic P atom. There is also no evidence for additional stabilization by cyclophosphazene ring or any of the pyrrolidinyl groups.

2

The effect of EDTA and EDDS on lead uptake and localization in hydroponically grown Pisum sativum L.

88%

Glinska S. , Michlewska S. , Grapinska M. , Seliger P. , Bartosiewicz R.

Acta Physiologiae Plantarum

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2014

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tom 36

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nr 02

EN

Pisum sativum plants were treated for 3 days with an aqueous solution of 100 μM Pb(NO₃)₂ or with a mixture of lead nitrate and ethylenediaminetetraacetic acid (EDTA) or [S,S]-ethylenediaminedisuccinic acid (EDDS) at equimolar concentrations. Lead decline from the incubation media and its accumulation and localization at the morphological and ultrastructural levels as well as plant growth parameters (root growth, root and shoot dry weight) were estimated after 1 and 3 days of treatment. The tested chelators, especially EDTA, significantly diminished Pb uptake by plants as compared to the lead nitrate-treated material. Simultaneously, EDTA significantly enhanced Pb translocation from roots to shoots. In the presence of both chelates, plant growth parameters remained considerably higher than in the case of uncomplexed Pb. Considerable differences between the tested chelators were visible in Pb localization both at the morphological and ultrastructural level. In Pb+EDTA-treated roots, lead was mainly located in the apical parts, while in Pb+EDDS-exposed material Pb was evenly distributed along the whole root length. Transmission electron microscopy and EDS analysis revealed that in meristematic cells of the roots incubated in Pb+EDTA, large electron-dense lead deposits were located in vacuoles and small granules were rarely noticed in cell walls or cytoplasm, while after Pb+EDDS treatment metal deposits were restricted to the border between plasmalemma and cell wall. Such results imply different ways of transport of those complexed Pb forms.

3

Bezpośrednia synteza azydków i tioli organicznych pochodnych glikolu etylenowego w zmodyfikowanej reakcji Appela

75%

Stefaniak M. , Jasiński M. , Urbaniak K. , Romański J. , Seliger P. , Gutowska N.

Chemik

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2014

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tom Vol. 68, nr 7

592--599

PL

Klasyczną metodę konwersji alkoholi pierwszorzędowych w odpowiednie halogenki alkilowe z użyciem trifenylofosfiny oraz tetrahalogenometanu, tzw. reakcję Appela, zaadoptowano do bezpośredniej syntezy terminalnych tioli i azydków organicznych pochodnych glikolu etylenowego oraz jego siarkowego analogu. W kluczowym etapie opisanej procedury one-pot, otrzymane in situ, w reakcji z N-bromosukcynimidem (NBS), odpowiednie dibromopochodne zostały przekształcone w związki docelowe w reakcji z nukleofilem siarkowym lub azotowym. Wybrane diazydki wykorzystano w syntezie nowych układów makrocyklicznych, które przetestowano pod kątem ich właściwości kompleksotwórczych.

EN

Classical method of conversion of primary alcohols into corresponding alkyl halides by usage of triphenylphosphine and tetrahalogenated methane, so-called Appel reaction, was adopted for the direct synthesis of terminal organic thiols and azides derived from ethylene glycol and its sulfurated analogue. In key step of the presented ‘one-pot’ protocol, corresponding dibromides, generated in situ via reaction with N-bromosuccinimide (NBS), were converted into desired products by treatment with appropriate sulfur or nitrogen nucleophile. A series of diazides and dithiols derived from (poly)ethylene glycols and their sulfur analogues were obtained. Selected diazides were utilized for the construction of novel macrocyclic systems, that were tested incontext of their complexing properties.