De Novo Design, Synthesis, and X-ray Crystal Structures of Pyrrolinone-Based .beta.-Strand Peptidomimetics
摘要:
The de novo design and synthesis of a novel non-peptide scaffolding for beta-strand/sheet mimics are described. The scaffold consists of repeating 3,5,5-trisubstituted pyrrolinone (enaminone) units punctuated with appropriate amino acid side chains. The iterative construction of the pyrrolinones exploits a highly efficient cyclization of metalloimines, the latter derived from C-terminal aldehydes and readily available alpha-substituted alpha-amino ester building blocks. As predicted by interactive computer modeling and confirmed by X-ray crystallography, the polypyrrolinones present the side chains and carbonyl hydrogen-bond accepters in a solid-state conformation which mimics polypeptide beta-sheets. Importantly, the enaminone NH protons form hydrogen bonds both intramolecularly, stabilizing the beta-strand conformation, and intermolecularly, promoting sheet formation. The presence or absence of the nitrogen protecting group controlled antiparallel versus parallel sheet formation.
De Novo Design, Synthesis, and X-ray Crystal Structures of Pyrrolinone-Based .beta.-Strand Peptidomimetics
摘要:
The de novo design and synthesis of a novel non-peptide scaffolding for beta-strand/sheet mimics are described. The scaffold consists of repeating 3,5,5-trisubstituted pyrrolinone (enaminone) units punctuated with appropriate amino acid side chains. The iterative construction of the pyrrolinones exploits a highly efficient cyclization of metalloimines, the latter derived from C-terminal aldehydes and readily available alpha-substituted alpha-amino ester building blocks. As predicted by interactive computer modeling and confirmed by X-ray crystallography, the polypyrrolinones present the side chains and carbonyl hydrogen-bond accepters in a solid-state conformation which mimics polypeptide beta-sheets. Importantly, the enaminone NH protons form hydrogen bonds both intramolecularly, stabilizing the beta-strand conformation, and intermolecularly, promoting sheet formation. The presence or absence of the nitrogen protecting group controlled antiparallel versus parallel sheet formation.
A Second-Generation Synthesis of Polypyrrolinone Nonpeptidomimetics: Prelude to the Synthesis of Polypyrrolinones on Solid Support
作者:Amos B. Smith、Hu Liu、Ralph Hirschmann
DOI:10.1021/ol0059293
日期:2000.7.1
[reaction: see text] A second-generation asymmetric synthesis of polypyrrolinones (3) has been achieved exploiting scalemic alpha-aminolactones (1) as building blocks. Imine formation between an appropriate lactone (1) and aldehyde (2), followed in turn by pyrrolinone ring construction promoted by KHMDS in the presence of 18-crown-6 and modified Swern oxidation furnished pyrrolinone aldehyde 3. This iterative