One thing I do know is that Cy5 and Cy5.5 can be treated under the conditions of
Fmoc removal by 20% piperidine in DMF, and also conditions for side-chain
deprotection and cleavage of the peptide from the resin after Fmoc solid phase
peptide synthesis. The conditions for deprotection and cleavage involve
treatment at room temperature with 90% TFA, 5% water, 2.5% thioanisole and 2.5%
ethanedithiol for 0.5 to 2 hours. I would be concerned about treatments
involving strong basic conditions.
Hope this helps in some way and good luck.... Let us all know how it turns out.
Regards, Dick
Richard Noble
PE Biosystems
850 lincoln Centre Drive
Foster City, CA 94404
USA
Tel: 650-638-5450
Fax: 650-638-6311
email: noblern@pebio.com
"Alain LAURENT" <a.laurent@eurosequence.com> on 11/24/99 09:25:41 AM
To: Recipients of ABRF List <abrf@aecom.yu.edu>
cc: (bcc: Richard Noble/FOS/PEC)
Subject: DNA SYN: CY3 and CY5 labelling
Dear ABRF's users
Has anyone has experience with CY3 or CY5 labelling ? Pharmacia recommends
to use very mild condition for deprotection. I understand perfectly that PAC
chemistry would be the best but I cannot use it at the moment Do you think
I can use normal protecting groups (like CBz, Abz and Gibu) anyway.? Does
24h at RT or 16h 37C should be better than 6h 55C ?
What about the amidite concentration used ? Is 100 mM not too high ? What
about the coupling time and the coupling yield ?
On the Cy3 and Cy5 there is a MMT protecting on the primary alcool . From
my experience the MMT protecting group is normaly less labile than DMT on
the MMT-NH-linker for example and a special procedure for deprotection is
necessary in this case . Should I use a special procedure for the last
de-MMTrytilation on CY3 and Cy5 ?
Thank you very much for any ideas
Best regards
Alain
**************************************
Alain LAURENT Ph. D
Oligonucleotide Chemistry
ESGS Groupe CYBERGENE
11, rue Claude Bernard
35 400 Saint MAL0
FRANCE
Tel: +33 (0)2 99 21 90 40
Fax: +33 (0)2 99 21 90 41
e-mail: a.laurent@eurosequence.com
http://www.eurosequence.com
**************************************