| Popis: |
The morphinan peptides N-(4,5α-epoxy-3,6-dihydroxy-17-methyl-6α,14α-ethenoisomorphinan-7α-carbonyl)-L-phenylalanine ethyl ester (4), N-(4,5α-epoxy-3,6-dihydroxy-17-methyl-6α,14α-ethenoisomorphinan-7α-carbonyl)-D-phenylalanine ethyl ester (5) and N-[N-(4.5α-epoxy-3.6-dihydroxy-17-methyl-6α,14α-ethenoisomorphinan-7α-carbonyl)glycinyl]-L-phenylalanine ethyl ester (6) have been prepared from 4,5α-epoxy-3,6-dimethoxy-17-methyl-6α,14α-ethenoisomorphinan-7α-carboxylic acid (7) and the protected amino acids. The morphinan moiety was coupled to the peptide residue via the acid chloride of 7, after which the morphinan peptides were O-demethylated with the aid of hydrogen bromide in glacial acetic acid. The dipeptide N-glycinyl-L-phenylalanine ethyl ester was synthesized via the Excess Mixed Anhydride method (EMA). The new morphinan peptides have been characterized by 1H and 13C NMR spectroscopy. For conformational analysis, the relative stabilities of two possible hydrogen bonds around the C7-C20 bond have been calculated on a model compound 11, using molecular mechanics. |
