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P F Torrence

Publications and source records attributed to P F Torrence.

At least 109 records · Page 6Linked to original sources

Synthesis and antiviral activity of 5-[(cyanomethylene)oxy]-2'-deoxyuridine.

To study the influence of substitution of CN for C identical to CH in the anti-herpes virus nucleoside 5-(propynyloxy)-2'-deoxyuridine (1), 5-[(cyanomethylene)oxy]-2'-deoxyuridine (2) was prepared. When the potassium salt of 5-hydroxy-2'-deoxyuridine was reacted with iodoacetonitrile in dry DMF, the bisalkylated product 3-(cyanomethyl)-5-[(cyanomethylene)oxy]-2'-deoxyuridine (3) was the major product with a lesser amount of 3-(cyanomethyl)-5-hydroxy-2'-deoxyuridine (5) and only a trace amount of the desired product (2). In contrast, when 5-hydroxy-2'-deoxyuridine was alkylated in water in the presence of 1 equiv of KOH, compound 2 was the major product. In cultures of primary rabbit kidney (PRK) cells, compound 2 showed an anti-herpes virus activity that was comparable to that of 1 and ara-A. Compound 2 did not inhibit incorporation of [Me-3H]dThd or [1',2'-3H]dUrd into DNA of PRK cells; however, its anti-herpes virus activity was completely prevented upon the addition of either dThd or dUrd.

Animals↗

5'-O-Monophosphoryladenylyl(2' goes to 5')adenylyl(2' goes to 5')adenosine is an antagonist of the action of 5'-O-triphosphoryladenylyl-(2' goes to 5')adenylyl(2' goes to 5')adenosine and double-stranded RNA.

5'-O-Monophosphoryladenylyl(2' goes to 5')adenylyl-(2' goes to 5')adenosine [(2' goes to 5')(pA)3] antagonizes the protein synthesis inhibitory effects of 5'-O-triphosphoryladenylyl-(2' goes to 5')adenylyl(2' goes to 5')adenosine by preventing activation of the (2' goes to 5')oligo(a)-activated ribonuclease which degrades mRNA. The oligoribonucleotide (2' goes to 5')(pA)3 also antagonizes the translational inhibitory capacity of poly(I).poly(C) in extracts of interferon-treated L cells, suggesting that (2' goes to 5')oligo(A) is the primary mediator of the protein synthesis inhibitory effects of poly(I).poly(C) in this cell-free system.

Adenine Nucleotides↗

Double-stranded RNA inhibits a phosphoprotein phosphatase present in interferon-treated cells.

In accord with previous studies, (I)n . (C)n, a potent inhibitor of the cell-free protein-synthesizing system of interferon-treated L cells, stimulates incorporation of 32P from [gamma-32P]ATP into the 67,000-dalton protein, P1. The double-stranded RNA (I)n . (br5C)n, which is inactive as an inhibitory of protein synthesis, does not stimulate phosphorylation of P1 under conditions approximating those of protein synthesis. However, we have found conditions under which (I)n . (br5C)n is approximately as effective as (I)n . (C)n in stimulating incorporation of label from [gamma-32P]ATP into 67,000-dalton protein. Upon transfer of labeled P1 from these conditions to those compatible with protein synthesis, there is a time-dependent decrease in label in the 67,000-dalton protein. This decrease is more rapid in the presence of (I)n . (br5C)n than in the presence of (I)n . (C)n. This differential decrease is also observed when 32P-labeled extracts are diluted into buffer containing 10 mM ATP, hexokinase and 1 and M glucose, or Escherichia coli alkaline phosphatase. A partial proteolytic digest of P1 labeled in the absence of double-stranded RNA or in the presence of (I)n . (C)n or (I)n . (br5C)n gives rise to similar peptide patterns. These results suggest that dephosphorylation as well as phosphorylation determines the net incorporation of 32P into P1. Moreover, these results suggest the existence of a phosphatase activity that may be inhibited more strongly by (I)n . (C)n than by (I)n . (br5C)n.

Animals↗

Comparative efficacy of antiherpes drugs against different strains of herpes simplex virus.

A large variety of antiherpes compounds was compared for their inhibitory activity against laboratory strains and clinical isolates of herpes simplex virus (HSV) type 1 and type 2. From studies performed in primary rabbit kidney cell cultures, six, E-5-(2-bromovinyl)-2'-deoxyuridine, E-5-(2-iodovinyl)-2'-deoxyuridine, 5-vinyl-2'-deoxyuridine, 2'-fluoro-5-iodoaracytosine, acycloguanosine, and 5-iodo-2'-deoxycytidine, emerged as the most potent and selective antiherpes agents. For HSV type 1, the 50% inhibitory doses (ID50) were 0.008, 0.012, 0.018, 0.017, 0.04, and 0.06 micrograms/ml, respectively; those for HSV type 2 were 1, 2, 0.1, 0.05, 0.04, and 0.3 microgram/ml, respectively. These compounds did not inhibit host-cell metabolism or replication of vaccinia virus except at concentrations 100--10,000 times greater than the ID50 for any HSV. All were significantly less inhibitory for a thymidine kinase (TK)-deficient mutant of HSV type 1 than for normal strains, suggesting that phosphorylation by virus-induced TK was required to produce specific inhibition of HSV replication.

Antiviral Agents↗

Interferon induction by mismatched analogues of polyinosinic acid . polycytidylic acid [(Ix,U)n.(C)n].

Interruption of the (I)n strand of (I)n.(C)n by unpaired bases [(U)] yielded mismatched analogues, (Ix,U)n.(C)n which were still effective as inducers of interferon, provided the I:U ratio (x) was equal or greater than 10. In highly sensitive interferon-induction systems such as primary rabbit kidney cells and human skin fibroblasts superinduced with cycloheximide and actinomycin D, (I10,U)n.(C)n and (I50,U)n.(C)n proved nearly as active as (I)n.(C)n. By virtue of their increased susceptibility to degradation by nucleases, (Ix,U)n.(C)n complexes with 10 less than or equal to x less than or equal to 50 may be expected not to persist as long in biological fluids as (I)n.(C)n, hence to induce fewer side effects.

Animals↗

Relative potencies of different anti-herpes agents in the topical treatment of cutaneous herpes simplex virus infection of athymic nude mice.

Thirteen established anti-herpes compounds have been directly compared in a single assay system for their effects on the development of herpetic skin lesions, and mortality associated therewith, in athymic nude (nu/nu) mice inoculated intracutaneously with herpes simplex virus type 1 (KOS). When applied topically (at 1% in a water-soluble ointment), phosphonoacetic acid, E-5-(2-bromovinyl)-2'-deoxyuridine, acycloguanosine, and trisodium phosphonoformate emerged as the most active agents.

Animals↗

5-O-Alkylated derivatives of 5-hydroxy-2'-deoxyuridine as potential antiviral agents. Anti-herpes activity of 5-propynyloxy-2'-deoxyuridine.

Alkylation of 5-hydroxyuridine or 5-hydroxy-2'-deoxyuridine with various activated alkylating agents in the presence of 1 equiv of NaOH gave a series of new nucleoside analogues which were evaluated for antiviral activity against vaccinia virus, herpes simplex-1 virus, and vesicular stomatitis virus in both primary rabbit kidney cells and human skin fibroblasts. One of these analogues, 5-propynyloxy-2'-deoxyuridine, was a potent inhibitor of herpes simplex virus. Structure-activity considerations suggest that the anti-herpes activity is dependent on the integrity of the acetylene group since substitution of phenyl, p-nitrophenyl, vinyl, carboxamido, or carboxyl for the triple bond led to diminished antiviral activity.

Antiviral Agents↗