COMPARATIVE-EVALUATION OF DIFFERENT METHODS FOR DISULFIDE BOND FORMATION IN SYNTHESIS OF THE HIV-2 ANTIGENIC DETERMINANT

The peptide H-Asn-Ser-Trp-Gly-Cys-Ala-Phe-Arg-Gln-Val-Cys-NHEt corresp onding to the 593-603 sequence of gp41 protein of the HIV-2 was used t o evaluate different methods for the removal of Acm-protection and sub sequent disulfide bond formation. The studied methods involved the tre atment by salts of heavy metals (silver and mercury) and subsequent cy clization by oxygen, potassium ferricyanide or hydrogen peroxide. The direct oxidative conversion of Acm-peptide to the corresponding cyclic disulfide by iodine under acidic and neutral conditions was investiga ted, and the structure of bt-products was also studied. The best resul ts were obtained using mercuric acetate followed by oxidation with hyd rogen peroxide. (C) Munksgaard 1997.