ISSN:
0947-3440
Keywords:
5′,5′-O-Di-AZT-O′-benzylphosphotriester
;
Homo-dinucleoside prodrugs
;
Anti-HIV chemotherapy
;
Nucleoside monophosphate
;
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The synthesis of 5′,5′-O-di-(3′-azido-2′,3′-dideoxythymidinyl)-O′-benzylphosphotriesters 1 as potential prodrugs of nucleoside monophosphates is described. The concept is applied to the antiretroviral nucleoside analog 3′-azido-2′,3′-deoxythymidine (AZT) 4. All derivatives 1 were synthesized by reaction of the tetra-n-butylammonium salt of di-AZT-phosphate 2b with different benzyl bromides or -chlorides 9. Compound 2b was obtained by a combination of phosphoamidite/H-phosphonate chemistry, subsequent oxidation to 2a, and cation exchange. The partition coefficients of 1 in an 1-octanol/water mixture show that all compounds exhibit a much higher lipophilicity than the parent nucleoside AZT (4). It was also shown, that 1 decomposes spontaneously under mild aqueous basic conditions (phosphate buffer (pH 7.5) and RPMI culture medium containing heat-deactivated fetal calf serum) releasing selectively the di-AZT phosphate anion 2. The half-lives of 1 could be adjusted within a wide range by changing the ring substituents of the benzyl group. Additionally, the mechanism of hydrolysis varies if the substituent is changed from a donor to an acceptor one. The described phosphotriesters 1 exhibit considerable antiviral activity in HIV-1- and HIV-2-infected CEM/O cells, whereas no activity was detected in the HIV-2-infected thymidine kinase-deficient CEM cell line. On the other hand, we could not detect any cytotoxicity of the described phosphotriesters. Consequently, compounds 1 should act as prodrugs or depot forms at least of antiviral nucleoside analogs.
Additional Material:
2 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jlac.1995199512306
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