title: Site-specific fluorescein labeling of human insulin.
abstract: Three fluorescein derivatives of human insulin (HI, 1) labeled at positions N(αA1) , N(αB1) and N(εB29) respectively, were synthesized using an N-trifluoroacetyl-based protecting group scheme. The Tfa protecting group introduced by reaction with ethyl trifluoroacetate was found to be stable in aqueous and organic media and efficiently removed under mild basic conditions.
authors.affiliation: Lilly Research Laboratories, Indianapolis, IN 46285, USA.
authors.forename: Fa
authors.initials: F
authors.lastname: Liu
authors.forename: Wayne D
authors.initials: WD
authors.lastname: Kohn
authors.forename: John P
authors.initials: JP
authors.lastname: Mayer
mesh_terms: D019793:Fluorescein / Q000737:chemistry*; D006801:Humans; D007328:Insulin / Q000737:chemistry*; D014269:Trifluoroacetic Acid / Q000737:chemistry
chemical_list: D007328:Insulin; D014269:Trifluoroacetic Acid; D019793:Fluorescein