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Zusammenfassung -Substituierte -Acylvinylphosphonate3 mitE-Konfiguration [R 2CO-CH=C(R 1)-P(O)(OR)2], werden in guten Ausbeuten durchWittig-Reaktion von Acylphosphonsäureestern1 [R 1CO-P(O)(OR)2,R 1=Alkyl oder Aryl] mit (2-Oxoalkyliden)triphenylphosphoranen2 [R 2CO-CH=PPh 3,R 2=Alkyl, O-Alkyl oder CH2 X (X=Br, OMe, CO2 Et)] erhalten.
A convenient route to -substituted dialkyl (E)-3-oxo-1-alkenylphosphonates
-Substituted dialkyl (E)--acylvinylphosphonates [R 2CO-CH=C(R 1)-P(O)(OR)2,3], are easily obtained in good yields byWittig-reaction of dialkyl acylphosphonates1 [R 1CO-P(O)(OR)2,R 1=alkyl or aryl) with 2-oxoalkylidene triphenylphosphoranes2 [R 2CO-CH=PPh 3,R 2=alkyl, O-alkyl and CH2 X (X=Br, OMe, CO2 Et)].
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Abstract

The substitution of a non-bridging oxygen by sulfur in a DNA intemucleotidic phosphorus residue creates a nucleophilic site which is amenable to labeling by reporter groups such as fluorophores or spin labels. Placement of a single phosphorothioate diester at a selected position allows site-specific attachment of the reporter group. Incorporating a phosphorothioate at each and every intemucleotidic phosphorous linkage allows the incorporation of multiple reporter groups, ideally one for each nucleoside residue.  相似文献   
3.
1. INTRODUCTION Since the first report of efficient polymer light emitting diode (PLED) in 1990, conjugated polymers have intrigued great interests because of substantial promise for electro-optical applications [1,2]. It is essential to develop novel str…  相似文献   
4.
Copolymers of fluorene-co-phenothiazine (P1) and thiophene-co-phenothiazine (P2) were prepared respectively by Wittig reaction. The synthesis, photo-physical and electroluminescent properties of the resulting polymers were analyzed by FT-IR, GPC, 1H-NMR, UV-Vis, Photoluminescence (PL), Electroluminescence (EL) and Cyclic Voltammetry (CV). Their single layer devices with configuration of ITO/polymers/Ca/Al were studied. GPC results revealed the weight-average molecular weight (Mw) was 3.0×103 and 5.4×103, respectively. The device with a single layer structure of ITO/P1/Ca/Al emits green light with the maximum peak at 552nm. However,the device with a single layer structure of ITO/P2/Ca/Al emit red light with the maximum peak at 616nm.  相似文献   
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