Synthesis of porcine brain natriuretic peptide-32 using silver tetrafluoroborate as a new deprotecting reagent of the S-trimethylacetamidomethyl group.

Silver tetrafluoroborate (AgBF4) in trifluoroacetic acid (TFA) has been found to cleave the S-trimethylacetamidomethyl (Tacm) group or the S-acetamidomethyl (Acm) group without affecting other functional groups in the peptide chain. Newly isolated porcine brain natriuretic peptide-32 (pBNP-32) was synthesized using AgBF4 and Cys(Tacm) derivatives. The synthetic pBNP-32 had the highest chick rectum relaxant activity among the ANP-BNP families.