Membrane‐permeable Triphosphate Prodrugs of Nucleoside Analogues

Abstract

The metabolic conversion of nucleoside analogues into their triphosphates often proceeds insufficiently. Rate-limitations can be at the mono-, but also at the di- and triphosphorylation steps. We developed a nucleoside triphosphate (NTP) delivery system (TriPPPro-approach). In this approach, NTPs are masked by two bioreversible units at the γ-phosphate. Using a procedure involving H-phosphonate chemistry, a series of derivatives bearing approved, as well as potentially antivirally active, nucleoside analogues was synthesized. The enzyme-triggered delivery of NTPs was demonstrated by pig liver esterase, in human T-lymphocyte cell extracts and by a polymerase chain reaction using a prodrug of thymidine triphosphate. The TriPPPro-compounds of some HIV-inactive nucleoside analogues showed marked anti-HIV activity. For cellular uptake studies, a fluorescent TriPPPro-compound was prepared that delivered the triphosphorylated metabolite to intact CEM cells.

Synthesis and Antiviral Evaluation of TriPPPro‐AbacavirTP, TriPPPro‐CarbovirTP, and Their 1′,2′‐cis‐Disubstituted Analogues

“…[13,28,29] The phosphoramidite route includest he couplingo fap reformed (non)symmetric phosphoramidite and an ucleoside diphosphate followed by oxidation. [13,28,29] The phosphoramidite route includest he couplingo fap reformed (non)symmetric phosphoramidite and an ucleoside diphosphate followed by oxidation.…”

“…[13,28,29] The phosphoramidite route includest he couplingo fap reformed (non)symmetric phosphoramidite and an ucleoside diphosphate followed by oxidation. [28] Here, we chose the H-phosphonate route, in which the phenylg roups of diphenyl H-phosphonatew ere displaced by 4-(hydroxymethyl)phenyldodecanoate 15 [28,42] to form the H-phosphonate diester 16 in ay ield of 57 %( Scheme 4). [28] Here, we chose the H-phosphonate route, in which the phenylg roups of diphenyl H-phosphonatew ere displaced by 4-(hydroxymethyl)phenyldodecanoate 15 [28,42] to form the H-phosphonate diester 16 in ay ield of 57 %( Scheme 4).…”

“…[29] An alternative route to prepare TriPPPro compounds includes the use of H-phosphonate chemistry to form ad imasked pyrophosphate unit first, which is next treatedw ith nucleoside monophosphates after activation. [28] The TriPPPro synthesis (Scheme 5) started with the activation of pyrophosphate 17 with trifluoroacetic anhydride (TFAA) followed by the addition of 1-methylimidazole. Next, diester 16 was activated with N-chlorosuccinimide to yield the phosphorochloridate followed by treatment with tetrabutylammonium phosphate.…”

“…In most cases,a bsence of the 3'-hydroxy group is responsible for immediate chain termination, whereas modified pentose scaffolds and nucleobases induce delayed chain termination. [13,28,29] With this in hand we wanted to examinet he antiviral activity of TriPPPro compounds of ABC, CBV,a nd their 1',2'-cis-carbocyclic counterparts. This nucleosidea nalogue comprises acarbocyclic dideoxydidehydrocore and a6-cyclopropylaminopurine nucleobase, which overcomes some disadvantages of its guanine derivative (carbovir,C BV) 2.Aseries of these 'carbovirs' was developed by Vince et al,w ho first discovered Herein we describe the synthesis of lipophilic triphosphate prodrugs of abacavir,c arbovir,a nd their 1',2'-cis-substituted carbocyclic analogues.…”

Synthesis of a Bioreversibly Masked Lipophilic Adenosine Diphosphate Ribose Derivative

“…Also in both cases,l ipophilic and enzymatically cleavable acyloxybenzyl moieties were used as masks for the modification of the terminal phosphate group in the nucleoside diphosphates and triphosphates, respectively. [7][8][9][10] Through the masking only of the terminal phosphate unit, the compoundss till featured negative charge(s). However,t his did not prohibit their cell uptake.…”