Small peptide purification blues

SIR,

I AM A STUDENT WORKING ON PEPTIDE CHEMISTRY. I HAVE A PROTECTED AMINO ACID “ARGININE” THE REACTION DOES NOT GO TO COMPLETION AND HENCE THERE IS UNREACTED ARGININE ALONG WITH THE PROTECTED ARGININE. I HAVE TRIED SEPARATION BY CONVENTIONAL COLUMN CHROMATOGRAPHIC METHODS (ALUMINA)  BUT RECOVERED A MIXTURE OF PROTEDTED AND UNREACTED ARGININE. SOLVENT SYSTEM USED WAS METHANOL –DCM. THE SPOT OF THE PRODUCT DOES NOT MOVE ON THE TLC EVEN IN AMMONIATED METHANOL. COULD YOU ADVICE ME ON HOW TO PROCEED WITH THIS SEPARATION AND ISOLATION.

MY EMAIL ADDRESS IS [Only registered users see links. ].

THANK YOU


 

Am 25.07.2007, 03:18 Uhr, schrieb samreen shaikh
<[Only registered users see links. ]>:


Please don't shout.

Have you checked the original publication for the synthesis of your
analogue, it should give a detailed description. If not, a
chemistry-related group may be more appropriate for this question.