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Andrew J Hampshire

Publications and source records attributed to Andrew J Hampshire.

2 recordsLinked to original sources

DNA sequence recognition by an imidazole-containing isopropyl-substituted thiazole polyamide (thiazotropsin B).

We have used DNA footprinting and fluorescence melting experiments to study the sequence specific binding of an imidazole-containing isopropyl-substituted thiazole polyamide (thiazotropsin B) to DNA. While the parent compound (thiazotropsin A) binds to the hexanucleotide sequence ACTAGT, changing one of the N-methylpyrrole groups to N-methylimidazole changes the preferred binding sequence to (A/T)CGCG(T/A). Experiments with DNA fragments that contain variants of this sequence suggest that the ligand can also bind, with lower affinity, to sequences which differ from this by 1bp in any position.

Base Sequence↗

Efficient solid-phase-based total synthesis of the bisintercalator TANDEM.

[reaction: see text] In this article, the first solid-phase-based total synthesis of TANDEM, a synthetic analogue of triostin A, is described. In initial studies, the synthesis incorporated depsipeptide formation, introduction of chromophores, and disulfide bond formation on the solid phase, prior to a final solution-phase macrolactamization, to give the target molecule. Although pure TANDEM was obtained in an overall yield comparable to those for all syntheses to date, the yield of the final cyclization was low (11%). A more efficient approach involved removal from the solid phase prior to disulfide bond formation. The resulting linear peptide underwent macrolactamization under mild conditions and high dilution. Final disulfide bond formation was essentially quantitative and gave the target molecule, TANDEM, in an overall yield of 18%. The final compound was assessed for its ability to bind to 5'-TpA sequences on DNA by DNase I footprinting. This efficient synthesis sets the stage for a study of the structure-activity relationship of TANDEM and the natural product triostin A, with analogues containing "point mutations" at every site within the cyclic compounds.

Anti-Bacterial Agents↗