Improved Synthesis and Isolation of 2′-<i>O</i>-Methyladenosine: Effective and Scalable Enzymatic Separation of 2′/3′-<i>O</i>-Methyladenosine Regioisomers
作者:Saúl Martínez-Montero、Susana Fernández、Tatiana Rodríguez-Pérez、Yogesh S. Sanghvi、Ke Wen、Vicente Gotor、Miguel Ferrero
DOI:10.1002/ejoc.200900348
日期:2009.7
develop a separation protocol. Upon extraction of the acylated products, the 3′-O-methyladenosine was isolated in 81 % yield and 97 % purity from the aqueous layer. Hydrolysis of acylated products in organic layer furnished 2′-O-methyladenosine in 67 % yield and 99 % purity. The separation process was successfully applied to the crude reaction mixture of methylated products (ca. 3:1 of 1/2) on 5-g scale
Novel enzymatic synthesis of levulinyl protected nucleosides useful for solution phase synthesis of oligonucleotides
作者:Javier Garcı́a、Susana Fernández、Miguel Ferrero、Yogesh S. Sanghvi、Vicente Gotor
DOI:10.1016/j.tetasy.2003.07.009
日期:2003.11
An efficient synthesis of 3' and 5'-O-levulinyl-2'-deoxy- and 2'-O-alkylribonucleosides has been developed front appropriate nucleosides by enzyme-catalyzed regioselective acylation in organic 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 1 and 3 in excellent yields. Similarly, Candida antarctica lipase B (CAL-B) provided 5'-O-levulinyl nucleosides 2 and 4 in high yields. 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 N-2-Ibu-5'-O-levulinyl-2'deoxygunaosine were synthesized on a 25 g scale. Additionally, PSL-C was reused to make the processes further economical. (C) 2003 Elsevier Ltd. All rights reserved.
Building Blocks for the Solution Phase Synthesis of Oligonucleotides: Regioselective Hydrolysis of 3‘,5‘-Di-<i>O</i>-levulinylnucleosides Using an Enzymatic Approach
作者:Javier García、Susana Fernández、Miguel Ferrero、Yogesh S. Sanghvi、Vicente Gotor
DOI:10.1021/jo020080k
日期:2002.6.1
opposite selectivity toward the hydrolysis at the 3'-position, affording 5'-O-levulinyl derivatives 4 in >70% yields. A similar hydrolysis procedure was successfully extended to the synthesis of 3'- and 5'-O-levulinyl-protected 2'-O-alkylribonucleosides 7 and 8. This work demonstrates for the first time application of commercial CAL-B and PSL-C toward regioselective hydrolysis of levulinyl esters with excellent