Reference

Effect of temperature and protonation upon the conformation of 2'-O-methyladenosine

Effect of temperature and protonation upon the conformation of 2'-O-methyladenosine. Correlation of conformational parameters in purine nucleosides. Hruska, F. E.In this study， 2140-79-6 and 58-61-7 are also used.; Wood, D. J.; Singh, H. (Dep. Chem., Univ. Manitoba, Winnipeg, Manitoba, Can.). Biochim. Biophys. Acta, 474(1), 129-40 (English) 1977. CODEN: BBACAQ. DOCUMENT TYPE: Journal CA Section: 33 (Carbohydrates) Section cross-reference(s): 22, 28 NMR studies of 2'-O-methyladenosine in 2H2O were carried out at variable temp. and p2H. The chem. shifts and H-H coupling constants are discussed in terms of the mol. conformation. 2'-O-Methylation has little influence on the conformation. At neutral p2H where the adenine base is not protonated, the molecules favor a 2'endo, gauche-gauche conformation. Protonation of the base at the N(1) position leads to a decrease in the 2'-endo, gauche-gauche bias. The data for 2'-O-methyladenosine and adenosine reveal the presence of a correlation between the sugar pucker and the C(5')-C(4') conformer distribution which is the inverse of the correlation previously reported for pyrimidine derivs. .

Novel enzymatic synthesis of levulinyl protected nucleosides useful for solution phase synthesis of oligonucleotides

Novel enzymatic synthesis of levulinyl protected nucleosides useful for solution phase synthesis of oligonucleotides. Garcia, Javier; Fernandez, Susana; Ferrero, Miguel; Sanghvi, Yogesh S.; Gotor, Vicente (Facultad de Quimica, Departamento de Quimica Organica e Inorganica, Universidad de Oviedo, Oviedo 33071, Spain). Tetrahedron: Asymmetry, 14(22), 3533-3540 (English) 2003 Elsevier Science B.V. CODEN: TASYE3. ISSN: 0957-4166. DOCUMENT TYPE: Journal CA Section: 33 (Carbohydrates) Section cross-reference(s): 7, 9 An efficient synthesis of 3'- and 5'-O-levulinyl-2'-deoxy- and 2'-O-alkylribonucleosides has been developed from appropriate nucleosides by enzyme-catalyzed regioselective acylation in org. solvents. Several lipases were screened in combination with acetonoxime levulinate as an acylating agent. Immobilized Pseudomonas cepacia lipase (PSL-C) was selected for acylation of the 3'-hydroxyl group in nucleosides, furnishing 3'-O-levulinylated products in excellent yields. Similarly, Candida antarctica lipase B (CAL-B) provided 5'-O-levulinyl nucleosides in high yields. 163759-49-7 and 2140-79-6 which are cas registry numbers of chemicals are mentioned. Base-protected cytidine and adenosine analogs were found to be good substrates for lipase-mediated acylations. To demonstrate the industrial utility of this method, 3'-O-levulinyl thymidine and N2-Ibu-5'-O-levulinyl-2'deoxyguanosine were synthesized on a twenty-five g scale. Addnl., PSL-C was reused to make the processes further economical. .