Premium
Studies on the Base‐Pairing Properties of N 7 ‐(2‐Deoxy‐β‐ D ‐ erythro ‐pentofuranosyl)guanine ( N 7 G d )
Author(s) -
Seela Frank,
Leonard Peter
Publication year - 1997
Publication title -
helvetica chimica acta
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.74
H-Index - 82
eISSN - 1522-2675
pISSN - 0018-019X
DOI - 10.1002/hlca.19970800424
Subject(s) - chemistry , guanine , nucleoside , base (topology) , base pair , nucleobase , stereochemistry , diastereomer , glycosylation , amine gas treating , cytosine , oligonucleotide , nucleic acid , medicinal chemistry , nucleotide , dna , organic chemistry , biochemistry , mathematical analysis , mathematics , gene
The base‐pairing properties of N 7 ‐(2‐deoxy‐β‐ D ‐erythro‐pentofuranosyl)guanine ( N 7 G d ; 1 ) are investigated. The nucleoside 1 was obtained by nucleobase‐anion glycosylation. The glycosylation reaction of various 6‐alkoxy‐purin‐2‐amines 3a ‐ i with 2‐deoxy‐3,5‐di‐ O ‐(4‐toluoyl)‐α‐ D ‐ erythro ‐pentofuranosyl chloride ( 8 ) was studied. The N 9 / N 7 ‐glycosylation ratio was found to be 1:1 when 6‐isopropoxypurin‐2‐amine ( 3d ) was used, whereas 6‐(2‐methoxyethoxy)purin‐2‐arnine ( 3i ) gave mainly the N 9 ‐nucleoside (2:1). Oligonucleotides containing compound 1 were prepared by solid‐phase synthesis and hybridized with complementary strands having the four conventional nucleosides located opposite to N 7 G d . According to T m values and enthalpy data of duplex formation, a base pair between N 7 G d and dG is suggested. From the possible N 7 G d dG base pair motives, Hoogsteen pairing can be excluded as 7‐deaza‐2′‐deoxyguanosine forms the same stable base pair with N 7 G d as dG.