Nucleosides as antiviral agents

Still other SAR studies included pyrimido[4,5-d]pyrimidine-2,4(l//,3//)dione and 2,4(l//,3//)-pteridinedione nucleosides as antiviral agents, 2-ary 1-6,8-disubstituted-quinazol-4(3//)-ones as fungicides <97IJHC51>, 3-N-substituted-thioureido-2-methyl-6-phenylthieno-[3,2-d]pyrimidin-4(3//)-ones <97JIC160> and 2-(dialkylamino, piperidino, morpholinomethyl)-... 

APPROACHES TO NOVEL ISOMERIC NUCLEOSIDES AS ANTIVIRAL AGENTS VasuNair... 

C.K. Chu, R.F. Schinazi, M.K. Ahn, G.V. Ullas and Z.P. Gu, Stmcture-activity relationships of pyrimidine nucleosides as antiviral agents for human immunodeficiency virus type 1 in peripheral blood mononuclear cells, J. Med. Chem., 32 612 (1989). 

Access to modified nucleosides. Base-modified nucleosides and nucleotides are very important for their biological properties. They can be found as antiviral agents (HBH, VZV, AIDS),93 95 in the study of DNA degradation,96,97 as fluorescent agents and as chemical probes of DNA structure.98 101 The access to nucleosides can be achieved by different methods ... 

Particularly promising as antiviral agents are the acyclic nucleoside phosphonates such as 9-[(2-phosphonylmethoxy)ethyl]adenine (PMEA, These compounds represent acyclic... 

For recent fluorinated nucleosides reviews, see (a) Meng, W-D. and Qing F-L. (2006) Fluori-nated nucleosides as antiviral and antitumor agents. Current Topics in Medicinal Chemistry, 6, 1499-1528 (b) Qing, F-L. and Qiu, X-L. (2007) Synthesis of gem-difluoromethylated sugar nucleosides. In Current Fluoroorganic Chemistry, ACS Symposium Series 949, pp. 305-322 and references cited therein. 

Structure of some of the purine nucleoside analogues used as antiviral agents. 

Nucleoside analogues are widely used as antiviral agents in the treatment in AIDS and AIDS-related complex. The only clinical agent approved in the United States for the treatment of AIDS is 3 -azido-3 -deoxythymidine (AZT) [54,55]. The molecular mechanism of action for this nucleoside includes conversion into its corresponding 5 -monophosphate by the action of cellular nucleoside kinase, followed by stepwise phosphorylation catalyzed by cellular nucleoside kinase to the corresponding 5 -triphosphate. These inhibit proviral DNA synthesis [55-57], catalyzed by HIV reverse transcriptase (RT), and incorporation to the 3 end of the growing DNA chain [55,58]. 

A general method for the synthesis of 3 -azido -2, 3 -dideoxy-ribofuranosyl nucleosides involves the reaction of methyl 3-azido-2,3-dideoxy-5-0-toluoyl-D-ribose with the nucleoside base in the presence of TMSOTf. A range of 3 -azido- and 3 -amino-2, 3 -dideoxypyriraidine ribonucleosides have been prepared and evaluated as antiviral agents. 

It was over fifteen years ago that I met first Prof. Tohru Ueda. He, a young professor, visited our company and gave us a lecture. He mentioned that EDU was notable as an antiviral agent. From that time, we had interest in the application of nucleoside analogues as antiviral agents. We wish to express our deepest sympathy for the loss of Prof. Ueda. 

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