selenolanthionine

The synthesis method of L-Selenolanthionine[1]: Bis(dicyclohexylammonium)bis(N-carbobenzoxy)-L-seleno-lanthionate (0.310 g) was dissolved by shaking with a mixture of 2 N H2SO4 (40 ml) and EtOAc (40 ml). The organic phase was separated, washed repeatedly with a few milliliters of dilute H2SO4 and H2O, dried over anhydrous Na2SO4, and evaporated. The resulting residue was dissolved in glacial AcOH (1 ml) and treated with 4 N HBr in glacial AcOH (1 ml). After 1 hr at 26°, Et2O (20 ml) was added and the resulting solid material was washed several times by decantation with Et2O. The hydrobromide salt was taken up in H2O (0.5 ml) and the pH of the resulting solution was adjusted to 5 with 2 N NH4OH. The precipitated product was washed with H2O (0.7 ml).

[1] J. Roy. Optically active selenium-containing amino acids. Synthesis of L-selenocystine and L-selenolanthionine. Journal of Organic Chemistry 35 2 (1970): 510–513.