50256-05-8Relevant articles and documents
Nucleotides. Part LIV. Synthesis of condensed N1-(2'-deoxy-β-D- ribofuranosyl)lumazines, new fluorescent building blocks in oligonucleotide synthesis
Rosler,Pfleiderer
, p. 1869 - 1881 (2007/10/03)
Various condensed areno[g]lumazine derivatives 2, 3, and 5-7 were synthesized as new fluorescent aglycones for glycosylation reactions with 2- deoxy-3,5-di-O-(p-toluoyl)-α/β-D-erythro-pentofuranosyl chloride (10) to form, in a Hilbert-Johnson-Birkofer reaction, the corresponding N1-(2'- deoxyribonucleosides) 15-21. The β-D-anomers 15, 17, 19, and 21 were deblocked to 24-27 and, together with N1-(2'-deoxy-β-D- ribofuranosyl)lumazine (22) and its 6,7-diphenyl derivative 23, dimethoxytritylated in 5'-position to 28-33. These intermediates were then converted into the 3'-(2-cyanoethyl diisopropylphosphoramidites) 34-39 which function as monomeric building block in oligonucleotide syntheses as well as into the 3'-(hydrogen succinates) 40-45 which can be used for coupling with the solid-support material. A series of lumazine-modified oligonucleotides were synthesized and the influence of the new nucleobases on the stability of duplex formation studied by measuring the T(m) values in comparison to model sequences. A substantial increase in the T(m) is observed on introduction of areno[g]lumazine moieties in the oligonucleotide chain stabilizing obviously the helical structures by improved stacking effects. Stabilization is strongly dependent on the site of the modified nucleobase in the chain.
Nucleosides. LIV. Synthesis and properties of 3'-azido- and 2',3'-dideoxy- 6,7-diphenyllumazine nucleosides
Cao,Pfleiderer
, p. 773 - 798 (2007/10/02)
The best approach for the synthesis of 1-(3-azido-2,3-dideoxy-β-D- erythro-pentofuranosyl)lumazine (5) and its 6,7-dimethyl- (4) and 6,7- diphenyl derivatives (3) has been found in the interconversion of the corresponding 1-(2-deoxy-β-D-threo-pentofuranosyl)-lumazines. Monomethoxytritylation at the 5'-position (17, 34, 49) followed by mesylation at the 3'-OH group and subsequent nucleophilic displacement by lithium azide afforded 19, 29 and 47 which were deprotected by acid treatment to give 3-5 in good yields. The syntheses of 1-(2,3-dideoxy-β-D-glycero- pentofuranosyl)- 6,7-diphenyllumazine (6) and its 6,7-dimethyl derivative (7) were achieved from 1-(2-deoxy-β-D-erythro-pentofuranosyl)- 6,7- diphenyllumazine and the corresponding 6,7-dimethyllumazine (26) via their 5'-O-p-toluoyl- (20, 30), and 3'-deoxy-3'-iodo derivatives (24, 31) to form, after radical dehalogenation and final deprotection, 6 and 7. The newly synthesized lumazine nucleosides have been characterized by elemental analyses, UV- and NMR spectra.