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An experiment was conducted to analyze the working of the bimolecular reaction of meso-tetrakis(2,6-dichlorophenyl)porphinato-oxo-manganeseIV, ((Cl8TPP)MnIV(O)) with different alkenes using kinetics and product identification. The results reveal that the reactivity of trans-Alkenes is more than cis isomers, that the speed of epoxidation is increased by electron donating substituents and that the decreasing stereoselectivity is shown by epoxide products. Polar, oxygen-containing ring-opened product with the trapping probe VI-Z is produced by the reaction. Rate-limiting growth of an alkene-derived pi-radical cation intermediate or carbon intermediate cannot be connected with the epoxidation process.

The pyrrole nitrogen of a tripyrrole peptide minor groove binding agent was used to transport catalytic entities to the phosphates, and the preparation of dienmicrogonotropen-a, -b, -c (5a, 5b and 5c) brought about the major groove of DNA. The DNase I footprint experiments are responsible for the affinity and specificity of binding between the 5'-(32p) 167-bp EcoRI/RsaI restriction fragment of pBR322 and 5a, 5b, 5c. The order 5c is greater than 5b is greater than 5a is greater than distamycin is the order of distortion followed by DNA.

Restrained molecular modeling and 2D HNMR and ID spectroscopy were employed to reveal the 1:1 complex of d(CGCAAATTTGCG)2 and the solution structures of d(CGCAAATTTGCG)2 with dien-microgonotropen-c (5c). The 2D (NOESY) spectra of the 1:1 complex and the ID (DNA imino protons) demonstrate assymetrical binding in the zone that is enriched with A + T and associated with (5'-A6T7T8T9G10). A break in C2v symmetry at the junction of A6T7 of the crystallized DNA is revealed by molecular modeling and NOE measurements of the 5c-bound and free DNA.

Competitive binding experiments conducted at 35 degrees centigrade with Hoechst 33258 (Ht) helped derive equilibrium constants in the case of minor groove binding by DNA oligomers with double-strands. Hoechst 33258 (Ht) is known to floresce when bound in the B-DNA minor groove. The order of affinity for the DNA:Ht2 species (KL1KL2 or KHt1KHt2) or DNA L2 is dien-microgonotropen-a, -b, -c (5a, 5b and 5c) where 5a is similar to 5b is similar to 5c is greater than Ht is greater than distamycin is greater than 2. A methyl group replaces the triamine substituents to yield lexitropsins 2.