Compound 1l Research Articles

Orally active trifluoromethyl ketone inhibitors of human leukocyte elastase.

This paper describes the development a series of peptidyl trifluoromethyl ketone inhibitors of human leukocyte elastase which are found to have excellent pharmacological profiles. Methods have been developed that allow for the synthesis of these inhibitors in stereochemically pure form. Two of these compounds, 1k and 1l, have high levels of oral bioavailability in several species. Compound 1l has entered development as ZD8321 and is presently undergoing clinical evaluation. These compounds demonstrate that peptidyl trifluoromethyl ketone inhibitors can achieve high levels of oral activity and bioavailability, and therefore they may prove useful as therapeutic agents in the treatment of diseases in which elastase is implicated.

Cyclic peptides.

cyclo(-L-Pro-L-Val-L-Pro-L-Val-) (1L) and cyclo(-L-Pro-D-Val-L-Pro-D-Val-) (1D) were synthesized by the conventional method for peptide synthesis. Conformations of 1L and 1D in solution were studied. Compound 1L has a cis-trans-cis-trans backbone conformation with C2 symmetry in CDCl3. This conformation is slightly different from that in crystalline state and in DMSO-d6 solution. Compound 1D has a cis-trans-cis-trans conformation in DMSO-d6 and an all-trans conformation in trifluoroethanol-d3. Compound 1L retarded stem-growth of rice seedlings and, in contrast, compound 1D promoted root-growth of rice seedlings.

ChemInform Abstract: INTRAMOLECULAR CYCLIZATION OF ALKYLHYDROXYLAMINES IN ACIDS

AbstractDie O‐Acyl‐3‐hydroxylaminobutylbenzole (I) cyclisieren in Trifluoressigsäure (II) oder in Gegenwart von Lewissäuren zu den Tetrahydrochinaldinen (III).

Intramolecular cyclization of alkylhydroxylamines in acids.

Alkylhydroxylamines having a benzene ring in the molecule were subjected to intramolecular cyclization in trifluoroacetic acid or in the presence of Lewis acids, and benzenefused six-membered heterocycles were obtained in moderate yields from the cyclization reaction of O-acylhydroxylamines. The effect of a methoxyl group on the benzene ring was also investigated. The m-methoxy compound (1j) cyclized to give 6-methoxy-2-methyl-1, 2, 3, 4-tetrahydroquinoline (2e), while the p-methoxy compound (1k or 1l) cyclized to give the same product (2e). These unusual results could be explained in terms of a spiro-intermediate (3a).