180477-13-8

Upstream product

• 83-01-2 diphenylcarbamic chloride 
• 217074-38-9 (2R,3S,5R)-2-Hydroxymethyl-5-{2-[2-(4-nitro-phenyl)-ethoxy]-purin-9-yl}-tetrahydro-furan-3-ol 
• 67616-35-7 2'-deoxyisoinosine 
• 217074-34-5 Acetic acid (2R,3S,5R)-2-acetoxymethyl-5-(2-hydroxy-purin-9-yl)-tetrahydro-furan-3-yl ester 

Downstream Products

• 180477-15-0 2-(N,N-diphenylcarbamoyl)oxy-9-[2-deoxy-5-O-(4,4'-dimethoxytrityl)-β-D-erythro-pentofuranosyl]-9H-purine 

Relevant academic research and scientific papers

Fluorescence properties and base pair stability of oligonucleotides containing 8-aza-7-deaza-2′-deoxyisoinosine or 2′-deoxyisoinosine

The fluorescence and the base pairing properties of 8-aza-7-deaza-2′-deoxyisoinosine (1) are described and compared with those of 2′-deoxyisoinosine (2). The corresponding phosphoramidites (11, 12) are synthesized using the diphenylcarbamoyl (DPC) residue for the 2-oxo group protection. The nucleosides 1 and 2 base pair with 2′-deoxy-5-methylisocytidine in DNA duplexes with antiparallel chain orientation and with 2′-deoxycytidine in a parallel DNA. These base pairs are less stable than the canonical dA-dT pair and that of 2′-deoxyinosine (4) with 2′-deoxycytidine. The fluorescence of the nucleosides 1 and 2 is quenched (～95%) in duplex DNA. The residual fluorescence is used to determine the Tm-values, which are found to be the same as determined UV-spectrophotometrically.

Thermal stability studies of the non canonical base pair between 5- methyl-isocytosine and isohypoxanthine

The hybridization properties of 5-methyl-isocytosine ((5Me)isoC) and isohypoxanthine (isoI) have been investigated by using ultraviolet melting techniques. These two bases were incorporated into heptadecanucleotides using the phosphoramidite chemistry. The base pair (5Me)isoC/isoI was found to be isoenergetic with the A/T base pair. A small destabilization was observed when isoI was located opposite T or G and can be interpreted by a pairing mode between these bases and isol in its lactam form.