26527-25-3Relevant academic research and scientific papers
Influence of Sulfur-Containing Diamino Acid Structure on Covalently Crosslinked Copolypeptide Hydrogels
Raftery, Eric D.,Gharkhanian, Eric G.,Ricapito, Nicole G.,McNamara,Deming, Timothy J.
, p. 3547 - 3553 (2018)
Biologically occurring non-canonical di-α-amino acids were converted into new di-N-carboxyanhydride (di-NCA) monomers in reasonable yields with high purity. Five different di-NCAs were separately copolymerized with tert-butyl-l-glutamate NCA to obtain covalently crosslinked copolypeptides capable of forming hydrogels with varying crosslinker density. Comparison of hydrogel properties with residue structure revealed that different di-α-amino acids were not equivalent in crosslink formation. Notably, l-cystine was found to produce significantly weaker hydrogels compared to l-homocystine, l-cystathionine, and l-lanthionine, suggesting that l-cystine may be a sub-optimal choice of di-α-amino acid for preparation of copolypeptide networks. The di-α-amino acid crosslinkers also provided different chemical stability, where disulfide crosslinks were readily degraded by reduction, and thioether crosslinks were stable against reduction. This difference in response may provide a means to fine tune the reduction sensitivity of polypeptide biomaterial networks.
Triply bridged (1,3,5) cyclophanes from cystine and lanthionine linkers-a comparison
Ranganathan,Venkateshwarlu,Babu,Reddy,Basha,Sarma,Vijay,Sastry
experimental part, p. 3923 - 3929 (2010/07/05)
The condensation of benzene 1,3,5-tricarbonylchloride with cystine-di-Me [H2N-CH(COOMe)-CH2-S-S-CH2-CH(COOMe)-NH 2] yielded triply bridged (1,3,5) cyclophane 1, which was shown by detailed spectral studies and molecular orbital calculations to have a D3 symmetry with conformationally identical linkers and a spherical topology. In sharp contrast, the (1,3,5) cyclophane 2 from the rarely studied lanthionine di-Me [H2N-CH(COOMe)-CH2-S-CH2-CH(COOMe)-NH 2], showed only a equatorial twofold symmetry. This work highlights the special properties of the -S-S- bridge in cystine, which makes it an exceptional synthon in nature and organic synthesis.
