The use of mass spectrometry in peptide chemistry

A review with 16 refs. Methods are detailed for derivatizing peptides (mg quantities) in order to provide sufficient volatility for mass spectrometry (at least 10-5 mm vapor pressure at 300 Deg is required). Three steps are used in producing the desired derivs.: (a) arginine side chains are converted to dimethylpyrimidyl ornithine by reaction with acetylacetone; (b) free amino groups are acetylated by reaction with Ac2O in order to avoid quaternization during permethylation; and (c) N, O, S permethylation is used to replace all H atoms not bound to C with a Me group by reacting the peptide with methylsulfinylmethide carbanion (DMSO-) to produce a peptide polyanion and then by adding MeI for methylation. With each mass spectrum obtained, the amino acid sequence is derived via a computer program similar to that of K. Biemann, et al. (1966). [on SciFinder (R)