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Title: Abc Amino Acids: Design, Synthesis, and Properties of New Photoelastic Amino Acids

Abstract

Photoisomerizable amino acids provide a direct avenue to the experimental manipulation of bioactive polypeptides, potentially allowing real-time, remote control of biological systems and enabling useful applications in nanobiotechnology. Herein, we report a new class of photoisomerizable amino acids intended to cause pronounced expansion and contraction in the polypeptide backbone, i.e., to be photoelastic. These compounds, termed Abc amino acids, employ a photoisomerizable azobiphenyl chromophore to control the relative disposition of aminomethyl and carboxyl substituents. Molecular modeling of nine Abc isomers led to the identification of one with particularly attractive properties, including the ability to induce contractions up to 13A in the backbone upon transa?cis photoisomerization. This isomer, designated mpAbc, has substituents at meta and para positions on the inner (azo-linked) and outer rings, respectively. An efficient synthesis of Fmoc-protected mpAbc was executed in which the biaryl components were formed via Suzuki couplings and the azo linkage was formed via amine/nitroso condensation; protected forms of three other Abc isomers were prepared similarly. A decapeptide incorporating mpAbc was synthesized by conventional solid-phase methods and displayed characteristic azobenzene photochemical behavior with optimal conversion to the cis isomer at 360 nm and a thermal cisa?trans half life of 100 min. at 80 AoC.

Authors:
 [1];  [2]
  1. ORNL
  2. Seoul National University
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Laboratory Directed Research and Development (LDRD) Program
OSTI Identifier:
930739
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Organic Chemistry; Journal Volume: 71; Journal Issue: 21
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; AMINO ACIDS; CONTRACTION; DESIGN; ISOMERS; POLYPEPTIDES; REMOTE CONTROL; SIMULATION; SYNTHESIS; azobenzene; unnatural amino acids; photoresponsive molecules; molecular modeling; Suzuki coupling

Citation Formats

Standaert, Robert F, and Park, Dr Seung Bum. Abc Amino Acids: Design, Synthesis, and Properties of New Photoelastic Amino Acids. United States: N. p., 2006. Web. doi:10.1021/jo060763q.
Standaert, Robert F, & Park, Dr Seung Bum. Abc Amino Acids: Design, Synthesis, and Properties of New Photoelastic Amino Acids. United States. doi:10.1021/jo060763q.
Standaert, Robert F, and Park, Dr Seung Bum. Sun . "Abc Amino Acids: Design, Synthesis, and Properties of New Photoelastic Amino Acids". United States. doi:10.1021/jo060763q.
@article{osti_930739,
title = {Abc Amino Acids: Design, Synthesis, and Properties of New Photoelastic Amino Acids},
author = {Standaert, Robert F and Park, Dr Seung Bum},
abstractNote = {Photoisomerizable amino acids provide a direct avenue to the experimental manipulation of bioactive polypeptides, potentially allowing real-time, remote control of biological systems and enabling useful applications in nanobiotechnology. Herein, we report a new class of photoisomerizable amino acids intended to cause pronounced expansion and contraction in the polypeptide backbone, i.e., to be photoelastic. These compounds, termed Abc amino acids, employ a photoisomerizable azobiphenyl chromophore to control the relative disposition of aminomethyl and carboxyl substituents. Molecular modeling of nine Abc isomers led to the identification of one with particularly attractive properties, including the ability to induce contractions up to 13A in the backbone upon transa?cis photoisomerization. This isomer, designated mpAbc, has substituents at meta and para positions on the inner (azo-linked) and outer rings, respectively. An efficient synthesis of Fmoc-protected mpAbc was executed in which the biaryl components were formed via Suzuki couplings and the azo linkage was formed via amine/nitroso condensation; protected forms of three other Abc isomers were prepared similarly. A decapeptide incorporating mpAbc was synthesized by conventional solid-phase methods and displayed characteristic azobenzene photochemical behavior with optimal conversion to the cis isomer at 360 nm and a thermal cisa?trans half life of 100 min. at 80 AoC.},
doi = {10.1021/jo060763q},
journal = {Journal of Organic Chemistry},
number = 21,
volume = 71,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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