Improvements in automated PNA synthesis using Boc/Z monomers.
An optimized automated PNA synthesis protocol is reported. Under optimal conditions the product yield of a test 17-mer PNA is approximately 90%. The average coupling yield is 99.4%. The synthesis strategy is Boc/Z and the deprotected amine is neutralized in situ. The monomers are added in molar excess to HATU and pre-activated for 60 s before delivery to the resin. The concentration of the activated monomers is 0.08 M during the couplings. Heteroselective solvation provides the highest coupling yields. Acetic anhydride is used as capping reagent followed by a piperidine wash. The protocol has been developed in a 5 mumol scale but is easily scaled up to 10-50 mumol scale syntheses on the automated synthesizer (ABI 433A).
Koch
T
T
PNA Diagnostics A/S, Copenhagen, Denmark.
Hansen
H F
HF
Andersen
P
P
Larsen
T
T
Batz
H G
HG
Otteson
K
K
Orum
H
H
D001704:Biopolymers; D002851:Chromatography, High Pressure Liquid; D005998:Glycine / Q000031:analogs & derivatives / Q000737:chemistry; D009696:Nucleic Acids / Q000138:chemical synthesis*; D010455:Peptides / Q000138:chemical synthesis*; D010880:Piperidines / Q000737:chemistry; D011687:Purines / Q000737:chemistry; D011744:Pyrimidinones / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D001704:Biopolymers; D009696:Nucleic Acids; D010455:Peptides; D010880:Piperidines; D011687:Purines; D011744:Pyrimidinones; C032727:piperidine; D005998:Glycine