- A traceless solid-phase synthesis of pteridines
-
The linking of pyrimidines to polystyrene supports via either a 2- or 4-thioether provides access to pteridines through solid-phase synthesis. Oxidative cleavage (dimethyldioxirane) followed by nucleophilic substitution by amines, azide, or water completes a traceless synthesis of pteridines.
- Gibson, Colin L.,La Rosa, Salvatore,Suckling, Colin J.
-
-
Read Online
- 6,7-Dimethyllumazine as a potential ligand for selective recognition of adenine opposite an abasic site in DNA duplexes
-
6,7-Dimethyllumazine more selectively binds to adenine (A) base opposite the abasic site in DNA duplexes (5′-TCC AGX GCA AC-3′/3′-AGG TCN CGT TG-5′, X = AP site (Spacer C3), N = A, T, C and G) than the other three nucleobases with a dissociation constant Kd of ca. 1.0 μM; substituted methyl groups enhance the binding affinity to A and the selectivity for A over T, compared to the parent molecule, lumazine. The Royal Society of Chemistry 2008.
- Ye, Zhiqiang,Rajendar, Burki,Qing, Dai,Nishizawa, Seiichi,Teramae, Norio
-
-
Read Online
- Evaluation of liquid chromatographic behavior of lumazinic derivatives, from α-dicarbonyl compounds, in different c18 columns: Application to wine samples using a fused-core column and fluorescence detection
-
Several C18 columns, packed with totally porous particles of different sizes and shell thicknesses, have been compared for simultaneous determination of α-dicarbonyl compounds, previous derivatization to lumazinic derivatives. Chromatographic conditions for the separation have been optimized for each column, and chromatographic parameters have been calculated and exhaustively compared. A core-shell C18 column provided the best results, and a HPLC method with fluorimetric detection has been proposed. The developed method has been validated in terms of linearity, precision, and sensitivity. Detection and quantification limits obtained were comprised between 0.02 and 0.30 and 0.07 and 1.0 ng mL-1, respectively, while RSD values obtained were lower than 6% and 5% in intraday and interday repeatability studies, respectively. The method has been applied to analysis of the α-dicarbonyl compounds in different types of wines. The higher levels of the total α-dicarbonyl compounds were found in sweet wines and the lower levels in white wines.
- Hurtado-Sanchez, Maria Del Carmen,Espinosa-Mansilla, Anunciacion,Rodriguez-Caceres, Maria Isabel,Duran-Meras, Isabel
-
-
- A prototype solid phase synthesis of pteridines and related heterocyclic compounds
-
The development of a versatile solid phase synthesis of bicyclic polyaza heterocycles including pteridines, purines, and deazapurines is described. The strategy comprises the linking of a pre-formed pyrimidine through a thioether at the 2 or 4 position to a polystyrene resin, the cyclisation of the second ring, and the direct or oxidative cleavage of the product from the resin by nucleophilic substitution. This provides not only for substituent variation in the second ring, but also for variation at the site of cleavage. Limitations in the scope of the methodology are set by the intrinsic reactivity of pyrimidinyl 2- or 4-thioethers which, whilst undergoing ready nitration at C5, are surprisingly difficult to alkylate and acylate.
- Gibson, Colin L.,La Rosa, Salvatore,Suckling, Colin J.
-
p. 1909 - 1918
(2007/10/03)
-
- Pteridine nucleotide analogs as fluorescent DNA probes
-
The invention provides novel pteridine nucleotides which are highly fluorescent under physiological conditions and which may be used in the chemical synthesis of fluorescent oligonucleotidcs. The invention further provides for fluorescent oligonucleotides comprising one or more pteridine nucleotides. In addition the invention provides for pteridine nucleotide triphosphates which may be used as the constituent monomers in DNA amplification procedures.
- -
-
-
- Pteridines, LXXI. - Synthesis and Photochemical Behaviour of 8- Substituted Lumazines
-
The 8-substituted lumazines 34-69 have been synthesized from 6-chloro-5-nitrouracil (1) and its 3-methyl derivative 2 via the corresponding 6-amino-5-nitrouracils 3-26, substituted at the amino nitrogen.The photochemical properties of the 8-substituted lumazines have been investigated.Various photoreactions were observed depending on the chemical nature of the N-8-side-chain and leading to an easy photodealkylation of the β-hydroxy-, β-methoxy-, and β-aminoethyl derivatives 34-44.Increasing donor properties of the β-substituent enhances the photolability which is expressed in a Norrish-type II cleavage reaction to the corresponding lumazines 70-75. 8-Cycloalkyllumazines 52-54 show photoreduction to 7,8-dihydrolumazines 76-78.The newly synthesized 8-substituted lumazine derivatives have been characterized by elementary analyses and UV spectra.Structural peculiarities due to the various substituents in position 6, 7, and 8 will be discussed.
- Ram, Vishnu J.,Knappe, Wolfgang R.,Pfleiderer, Wolfgang
-
p. 762 - 779
(2007/10/02)
-