There is an alternative method that uses B-mercaptoethanol, I think the
reference is: ERITJA_R, et al TETRAHEDRON, 1987, Vol.43, No.12,
pp.2675-2680. I haven't used this method myself so cannot comment on its
efficiency.
Kevin
At 18:27 14/07/99 -0700, you wrote:
>
> A question for the peptide synthesis experts. We have a peptide with
>two cysteine residues, whose side chains are protected with an SBut group.
>The structure of the side chain therefore is CH2-S-S-But. So far we have
>been unsuccessful to selectively remove the SBut groups using two
>procedures that we found in the literature. One uses nBu3P in NMP/water
>(9:1) and the other uses nBu3P in 0.1M ammonium acetate, pH
>7.8/iso-propanol (1:1).
> Can anybody recommend a procedure that will deprotect the cysteines
>without affecting the other protecting groups in the peptide, which was
>synthesized using the Fmoc chemistry? Our ultimate goal is to modify the
>cysteine residues with palmitic acid moieties before we do the Tfa
>deprotection and peptide cleavage from the resin.
>
>Thanks,
>
>Chris (turck@itsa.ucsf.edu)
>
>
_______________________________________
Kevin Howland
Protein Science Facility Manager
Research School of Biosciences
University of Kent
Canterbury CT2 7NJ
Tel: +44-1227-764000 ext 7987
Fax: +44-1227-763912
email: k.howland@ukc.ac.uk