Unfortunately, N-methylpiperidine is a tertiary amine, not a secondary
amine, and, if it cleaved the Fmoc at all, would do so very slowly. I
have heard of people using morpholine to cleave Fmoc, but it is much
slower than piperidine. I believe dimethylamine has also been used, don't
know the kinetics. Piperidine has been favored because it picks up the
dibenzofulvene after the Fmoc comes off, so it doesn't add to sensitive
amino acids, such as Asp, in the growing peptide. I suppose one desperate
measure might be the total hydrogenation of pyridine to get piperidine, but
it's not one I'd recommend.
Angela C. Murphy
On Wed, 13 Dec 2000, David A. Schooley wrote:
> I have wondered about the feasibility of switching to
> N-methylpiperidine, which must be of similar basicity and was used as
> the coupling base in HP protein sequencers. However, I didn't think
> we should switch because with extra trouble we can order piperidine.
>
> David
> --
> David A. Schooley
> Dept. of Biochemistry/330
> Univ. of Nevada
> Reno, NV 89557
> schooley@unr.edu
> tel: (775) 784-4136; fax (775) 784-1419
> NOTE NEW AREA CODE: Mandatory after 5/15/99
>
*******************************************
Angela C. Murphy, Chemist
Lab. of Cell Biology, NHLBI, NIH
3 Center Drive, MSC 0301, Rm. B1-22
9000 Rockville Pike
Bethesda, MD 20892-0301 USA
tel.: (301) 496-2324
fax: (301) 402-1519
email: acmurphy@helix.nih.gov
*******************************************
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