Methyl 2-amino-5-iso­propyl-1,3-thia­zole-4-carboxyl­ate

The title compound, C8H12N2O2S, forms a supramolecular network based on N-HN hydrogen-bonded centrosymmetric dimers that are linked in turn by N-HO contacts

A modified synthesis of 4-chromanones

Problems in the synthesis of 4-chromanones by condensation of 2-hydroxyacetophenones with formaldehyde can be avoided by the isolation of the Mannich base hydrochlorides and cyclization by titration with potassium hydroxide

3-Nitro-1-(triisopropylsilyl)-1H-pyrrole

The nitration of 1-(triisopropylsilyl)-1H-pyrrole leads to a mixt. of products following partial acid cleavage of the triisopropylsilyl protecting group. Structural detn. showed the isolated products to be 3-nitro-1-(triisopropylsilyl)-1H-pyrrole, C13H24N2O2Si (I), and 2,4-dinitropyrrole. In the solid state, I exists as discrete mols. with only weak C-H...nitro H bonds between them. Crystallog. data are given

DNA sequence recognition by an isopropyl substituted thiazole polyamide

We have used DNA footprinting and fluorescence melting experiments to study the sequence-specific binding of a novel minor groove binding ligand (thiazotropsin A), containing an isopropyl substituted thiazole polyamide, to DNA. In one fragment, which contains every tetranucleotide sequence, sub-micromolar concentrations of the ligand generate a single footprint at the sequence ACTAGT. This sequence preference is confirmed in melting experiments with fluorescently labelled oligonucleotides. Experiments with DNA fragments that contain variants of this sequence suggest that the ligand also binds, with slightly lower affinity, to sequences of the type XCYRGZ, where X is any base except C, and Z is any base except G

DNA sequence recognition by an isopropyl substituted thiazole polyamide

We have used DNA footprinting and fluorescence melting experiments to study the sequence-specific binding of a novel minor groove binding ligand (thiazotropsin A), containing an isopropyl substituted thiazole polyamide, to DNA. In one fragment, which contains every tetranucleotide sequence, sub-micromolar concentrations of the ligand generate a single footprint at the sequence ACTAGT. This sequence preference is confirmed in melting experiments with fluorescently labelled oligonucleotides. Experiments with DNA fragments that contain variants of this sequence suggest that the ligand also binds, with slightly lower affinity, to sequences of the type XCYRGZ, where X is any base except C, and Z is any base except G

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 I bp in any position

Methyl 2-amino-4-(methoxymethyl)thiazole-5-carboxylate

The synthesis and structure of 2-amino-4-(methoxymethyl)-thiazole-5-carboxylic acid Me ester (C7H10N2O3S) are reported. Crystallog. data and at. coordinates are given. The two crystallog. independent conformations found differ only by the rotational positions adopted by their methoxymethyl substituents. Intermol. contacts are dominated by H bonding involving the amine H atoms

Synthesis of novel DNA binding agents: indole-containing analogs of bis-netropsin

Mol. modeling studies showed that indole dicarboxylic acids are potential linkers for the synthesis of bisnetropsin analogs with a good fit to the minor groove of DNA. To test this hypothesis, 2-carboxyindole-6-acetic acid, indole-2,6-dicarboxylic acid, 6-(2-carboxyethyl)indole-2-carboxylic acid, and 6-(2-carboxy-1-ethenyl)indole-2-carboxylic acid were prepd. and coupled to 3-[1-methyl-4-(1-methyl-4-aminopyrrole-2-carboxamido)pyrrole-2-carboxamido]dimethylaminopropane. Similarly, indole-2,5-dicarboxylic acid was prepd. and coupled to 3-[1-methyl-4-(1-methyl-4-aminopyrrole-2-carboxamido)pyrrole-2-carboxamido]propionamidine hydrochloride. Some derivs. showed esp. strong binding at AT rich regions as shown by footprinting studies