80791-87-3Relevant articles and documents
An efficient process for synthesis of 2′-O-methyl and 3′-O-methyl guanosine from 2-aminoadenosine using diazomethane and the catalyst stannous chloride
Kore, Anilkumar,Parmar, Gaurang,Reddy, Srinu
, p. 307 - 314 (2007/10/03)
An improved strategy for the selective synthesis of 2′- O -methyl and 3′- O -methyl guanosine from 2-aminoadenosine is reported by using the catalyst stannous chloride. The regioselectivity of the 2′ and 3′- O -alkylation was achieved by optimizing the addition, timing, and concentration of the catalysts and diazomethane during the methylation reaction. An efficient and selective alkylation at 2′-OH of 2-aminoadenosine was achieved by mixing a stoichiometric amount of stannous chloride at room temperature in DMF. The reaction mixture was stirred at 50°C for 1 min and immediately followed by addition of diazomethane. The resulting 2′- O -methyl 2-aminoadenosine was treated with the enzyme adenosine deaminase, which resulted in an efficient conversion to the desired 2′- O -methylguanosine (98% yield). The product was isolated by crystallization. In contrast, the methylation at 3′-OH of 2-aminoadenosine was achieved by mixing a stoichiometric amount of stannous chloride in DMF and stirring at 50°C for 15 min, followed by addition of diazomethane. The resulting mixture containing 3′- O -methyl-2- aminoadenosine in 90% yield and 2′- O -methyl-2-aminoadenosine in 10% yield was treated with the enzyme adenosine deaminase, which preferentially deaminated only 3′- O -methyl-2-aminoadenosine, resulting in the production of 3′- O -methylguanosine in 88% yield. Due to the extremely low solubility 3′- O -methylguanosine, the compound precipitated and was isolated by centrifugation. This synthetic route obviates the chromatographic purification. Selective monomethylation is achieved by using the unprotected ribonucleoside. As a result, the method described herein represents a significant improvement over the current synthetic approach by providing superior product yield and economy, a much more facile purification of 2′,3′- O -methylated isomers, and eliminating the need for protected ribonucleosides reagents. Copyright Taylor & Francis Group, LLC.
2'-O-alkylnucleotides as well as polymers which contain such nucleotides
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, (2008/06/13)
Oligonucleotides having the general formula, STR1 in which B denotes an arbitrary nucleobase, A equals 0 or CH2 ; X or Z equals O, S, NH or denotes CH2 whereby X and Z can be the same or different, V and W denote O, S, Se, NH2/
Process for the preparation of 2'-O-alkyl purine phosphoramidites
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, (2016/06/29)
2'-O-alkylated guanosine, uridine, cytidine, and 2,6-diaminopurine 3'-O-phosphoramidites are prepared by alkylating nucleoside precursors, adding suitable blocking groups and phosphitylating. Alkylation is effected on 2,6-diamino-9-(β-D-ribofuranosyl)purine followed by deamination to prepare guanosine 2'-O-alkylated 3'-O-phosphormidites. Alkylation is effected on a dialkyl stannylene derivative of uridine to prepare uridine 2'-O-alkylated 3'-O-phosphormidites. Alkylation is effected directly on cytidine to prepare cytidine 2'-O-alkylated 3'-O-phosphormidites. Alkylation is effected directly on 2,6-diaminopurine to prepare 2,6-diaminopurine 2'-O-alkylated 3'-O-phosphormidites.
Novel adenosine derivatives and pharmaceutical composition containing them as an active ingredient
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, (2008/06/13)
Novel adenosine compounds of the formula (I): STR1 wherein R1, R2 and R3 are hydrogen or a lower alkyl group; X is hydrogen, a lower alkyl group, an amino group or halogen; and Y is hydrogen or a lower alkyl group, exhibit utility as antihypertensive agents.
Nucleic acid related compounds. 36. Synthesis of the 2'-O-methyl and 3'-O-methyl ethers of guanosine and 2-aminoguanosine and correlation of O'-methylnucleoside 13C nmr spectral shifts
Robins, Morris J.,Hansske, Fritz,Bernier, Salwa E.
, p. 3360 - 3364 (2007/10/02)
A modified trimethylsilylation of guanosine (1) followed by in situ replacement of the 6-trimethylsilyloxy group with ammonia at 150 deg C gave 2,6-diamino-9β-D-ribofuranosylpurine (2) in 92percent yield.Treatment of 2 with diazomethane in the presence of tin(II) chloride dihydrate gave the 2'-O-methyl (3) and 3'-O-methyl (4) ethers of 2 in 98percent combined yield.The ratios of 3/4 could be varied from 51:47 to 34:64 by changing the amount of catalyst used.Treatment of 3 and 4 with adenosine deaminase resulted in clean conversion of these 2-aminoadenosine ethers to 2'-O-methylguanosine (5) and 3'-O-methylguanosine (6), respectively, in optimized yields of 40percent and 54percent overall from 1.The 13C nmr data for six ribonucleosides and their isomeric methyl ether derivatives have been correlated to provide a convenient method of identification.
