Synthesis of 6-Substituted Purine N7-(2-Deoxy-β-D-Ribonucleosides) via Anion Glycosylation and Anomerization During the N7/N9-Glycosyl Transfer
摘要:
The synthesis of the 7-(2-deoxy-beta-D-erythro-pentofuranosyl) adenine (Ib) as well as the corresponding hypoxanthine- and purine nucleosides 3 and 4 is described employing the stereoselective nucleobase anion glycosylation. The N-7/N-9- isomer distribution of the 6-substituted purine (2-deoxyribonucleosides) depends on 6-substituent. Glycosyl transfer of 8a resulted in anomerization and yielded a mixture of the anomeric 6-methoxypurine N-9-(2-deoxy-D-ribonucleosides) 7a/7d. The preferred glycosylic bond conformation of purine N-7-(2-deoxyribonucleosides) is anti.
Pentenyl ribosides: new reagents for purine nucleoside synthesis
摘要:
Protected pent-4-enyl ribosides and deoxyribosides were synthesized as reagents for the preparation of nucleosides and deoxynucleosides. Reaction of pent-4-enyl 2',3',5'-tri-O-benzoyl-D-erythro-pentofuranoside with five nucleobases in the presence of N-iodosuccinimide/trifluoromethanesulfonic acid (NIS/TfOH) produced the N-9-beta-nucleosides in 50-70% yields. Pent-4-enyl-2-deoxy-3',5'-di-O-p-toluyl-alpha-D-erythro-pentofuranoside coupled with 6-chloropurine in the presence of iodonium dicollidine perchlorate (IDCP) to produce a mixture of deoxynucleoside isomers (N-9, N-7, alpha,beta) in 91% yield. Under the same conditions, coupling of 6-chloropurine with pent-4-enyl 2'-deoxy-3',5'-O-(tetraisopropyldisiloxane-1,3-diyl)-D-erythro-pentofuranoside produced only N-9alpha and N-9beta products in 40% total yield. The N-9beta nucleoside was the only product of the reaction of 6-chloropurine with pent-4-enyl 2'-O-benzoyl-3',5'-O-(tetraisopropyldisiloxane-1,3-diyl)-D-erythro-pentofuranoside in the presence of NIS/TfOH. Pent-4-enyl ribosides appear to be useful reagents for the synthesis of ribo- and deoxyribonucleosides under mild (NIS/TfOH) or neutral (IDCP) conditions.
A convenient synthesis of 2′-deoxy-6-thioguanosine,<i>ara</i>-guanine,<i>ara</i>-6-thioguanine and certain related purine nucleosides by the stereospecific sodium salt glycosylation procedure
作者:Naeem B. Hanna、Kandasamy Ramasamy、Roland K. Robins、Ganapathi R. Revankar
DOI:10.1002/jhet.5570250653
日期:1988.11
A simple and high-yield synthesis of biologically significant 2′-deoxy-6-thioguanosine (11), ara-6-thioguanine (16) and araG (17) has been accomplished employing the Stereospecificsodiumsaltglycosylation method. Glycosylation of the sodiumsalt of 6-chloro- and 2-amino-6-chloropurine (1 and 2, respectively) with 1-chloro-2-deoxy-3,5-di-O-(p-toluoyl)-α-D-erythro-pentofuranose (3) gave the corresponding
Synthesis of 2'-deoxytubercidin, 2'-deoxyadenosine, and related 2'-deoxynucleosides via a novel direct stereospecific sodium salt glycosylation procedure
作者:Zygmunt Kazimierczuk、Howard B. Cottam、Ganapathi R. Revankar、Roland K. Robins
DOI:10.1021/ja00333a046
日期:1984.10
Method for the production of 2'-deoxyadenosine compounds
申请人:BRIGHAM YOUNG UNIVERSITY
公开号:EP0173059B1
公开(公告)日:1989-11-29
HANNA, NACEM B.;RAMASAMY, KANDASAMY;ROBINS, ROLAND K.;REVANKAR, GANAPATHI+, J. HETEROCYCL. CHEM., 25,(1988) N, C. 1899-1903
作者:HANNA, NACEM B.、RAMASAMY, KANDASAMY、ROBINS, ROLAND K.、REVANKAR, GANAPATHI+