30747-22-9

Upstream product

• 134222-17-6 C₁₆H₃₁N₅O₂Si₃ 
• 13035-61-5 1,2,3,5-tetraacetylribose 
• 30747-23-0 Acetic acid (2R,3R,4R,5R)-4-acetoxy-5-acetoxymethyl-2-(2-acetylamino-6-oxo-1,6-dihydro-purin-9-yl)-tetrahydro-furan-3-yl ester 
• 59278-00-1 2-acetoxyethyl acetoxymethyl ether 
• 3056-33-5 2,9-diacetylguanine 
• 19962-37-9 N-(6-oxo-6,9-dihydro-1H-purin-2-yl)acetamide 

Downstream Products

• 185610-61-1 Acetic acid (2R,3R,4R,5R)-4-acetoxy-5-acetoxymethyl-2-(2-acetylamino-6-diphenylcarbamoyloxy-purin-7-yl)-tetrahydro-furan-3-yl ester 
• 30747-23-0 Acetic acid (2R,3R,4R,5R)-4-acetoxy-5-acetoxymethyl-2-(2-acetylamino-6-oxo-1,6-dihydro-purin-9-yl)-tetrahydro-furan-3-yl ester 
• 75128-73-3 2-acetylamino-9-(2-acetoxyethoxymethyl)purine-6-one 
• 91702-60-2 7-<(2-acetoxyethoxy)methyl>-N²-acetylguanine 
• 2958-98-7 3-methylguanine 

Relevant academic research and scientific papers

Tautomerism and regioselectivity in ribosylation of guanine

N2-acetyl- and 9,N2-diacetylguanines were subjected to reaction with tetraacetylribose in the presence of p-toluenesulfonic acid. Unlike the ribosylation of diacetylguanine, which gives 7-riboside as a kinetic product, the reaction of monoacetylguanine produces directly a mixture of 7- and 9-ribosides. This reflects N7H right arrow-left arrow N9H tautomerism of the guanine substrate and supports the hypothesis that only the unsubstituted nitrogens of the imidazolium portion of guanine (either N7 or N9) react directly with a sugar cation.

Regioselectivity and mechanism of transpurination reactions in the guanine nucleosides series

The transpurination reaction of the fully acetylated derivatives of guanosine and its 7-β-D-ribofuranosyl regioisomer with 2-acetoxyethyl acetoxymethyl ether has been studied using high performance liquid chromatography (HPLC). The regioselectivity of glycosyl exchange observed in the early stages of the reaction suggests that the unsubstituted nitrogen atoms of the imidazole portion (N7 and N9) are, exclusively, sites of direct glycosylation in the case of guanine derivatives. The results lead to the conclusion that the mechanism of the glycosylation reaction of guanine is different to that of adenine.

Nucleic acid related compounds. 93. A solution for the historic problem of regioselective sugar-base coupling to produce 9-glycosylguanines or 7-glycosylguanines

Per(trimethylsilyl)-2-N-acylguanine derivatives and tetra-O-acylpentofuranoses were coupled [tin(IV) chloride or titanium(IV) chloride catalysis] to give predominant formation of 7-glycosylguanines. With TiCl4, a fortuitous organic/aqueous partitioning allowed isolation of 7-glycosylguanines from the 7/9 isomer mixtures. Per(trimethylsilyl)-2-N-acyl-6-O-(diphenylcarbamoyl)guanine derivatives and tetra-O-acylpentofuranoses underwent regioselective coupling (trimethylsilyl trifluoromethanesulfonate catalysis) to give 9-glycosylguanines. The 6-O-(diphenylcarbamoyl)peracyl-9-β-D-ribofuranosyl isomer was shown to be both the xinetic and thermodynamic coupling product. Deprotection of all of the peracyl coupling products was effected under mild conditions to give good to high yields of guanine nucleoside analogues. These methodologies provide solutions for the regioselective synthesis of 7- and 9-glycosylguanine nucleosides.

A Regiocontrolled Synthesis of N7- and N9-Guanine Nucleosides

The reaction of 2-O-acetylated and 2-O-benzoylated glycosides 3a,b/4a,b with silylated N2-acetylguanine 7 selectively gave N7-guanine nucleosides 8a,b/9a,b under kinetically controlled conditions (SnCl4/CH3CN, room temperature), whereas 2-O-benzoylated glycosides 3b/4b selectively gave isomeric N9-guanine nucleosides 10b/11b under termodynamically controlled conditions (TMSOTf/(CH2Cl)2, reflux).Unambiguous assignment of nucleoside structure was accomplished after hydrolysis (NH3/MeOH) of the initial products to the known nucleosides 8c, 9c, 10c, and 11c followed by 1H NMR and 13C NMR spectral analysis.The described procedures provide the best method to date for the selective synthesis of either N7- or N9-guanine nucleosides from a common substrate.