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. 1982 Apr 1;203(1):331–334. doi: 10.1042/bj2030331

Reductive methylation of proteins with sodium cyanoborohydride. Identification, suppression and possible uses of N-cyanomethyl by-products.

M J Gidley, J K Sanders
PMCID: PMC1158228  PMID: 7103947

Abstract

Reductive methylation of protein amino groups with formaldehyde and sodium cyanoborohydride is shown to give up to 25% yield of N-cyanomethyl (-CH2CN) product; on work up of the reaction this is hydrolysed back to starting amine, lowering the methylation yield. Addition of metal ions such as Ni2+, which complex with free cyanide ion, improve reductive methylation yields by suppressing by-product formation. The N-cyanomethyl group itself, produced in good yield when cyanide ion replaces cyanoborohydride, may have some value as a reversible modifier of amino groups in proteins.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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