Stereoselective Synthesis of Thiophenedimethyl- and Benzenedimethyl- alpha,alpha'-Bridged Bis(glycines).
作者:Kristin Hammer、Tore Benneche、Håkon Hope、Kjell Undheim、Elemér Fogassy、Charles A. McAuliffe、Stenbjörn Styring、Cecilia Tommos、Kurt Warncke、Bryan R. Wood
DOI:10.3891/acta.chem.scand.51-0392
日期:——
Conformationally constrained cystine analogues have been synthesized which have an all-carbon backbone-chain as a bridge between the alpha,alpha'-positions in two glycine units. An aromatic ring consisting of a 1,2-disubstituted benzene or a 2,3- and 2,5-disubstituted thiophene has been inserted into the bridge. Chiral auxiliaries were used to effect stereoselective syntheses of the (S,S)-bis(amino acids). The latter were further derivatized as Fmoc-derivatives suitable for peptide syntheses. The product 2,3-bis[(2R,5S)-(2,5-dihydro-3,6-dimethoxy- 2-isopropyl-5-pyrazinyl)methyl]-5-methylthiophene has been subjected to X-ray analysis.