Reactivity of intein thioesters: appending a functional group to a protein was written by Kalia, Jeet;Raines, Ronald T.. And the article was included in ChemBioChem in 2006.Formula: C25H15NO9 This article mentions the following:
The success of genome sequencing has heightened the demand for new means to manipulate proteins. An especially desirable goal is the ability to modify a target protein at a specific site with a functional group of orthogonal reactivity. Here, we achieve that goal by exploiting the intrinsic electrophilicity of the thioester intermediate formed during intein-mediated protein splicing. Detailed kinetic analyses of the reaction of nitrogen nucleophiles with a chromogenic small-mol. thioester revealed that the α-hydrazino acetyl group was the optimal nucleophile for attacking a thioester at neutral pH to form a stable linkage. A bifunctional reagent bearing an α-hydrazino acetamido and azido group was synthesized in high overall yield. This reagent was used to attack the thioester linkage between a target protein and intein, and thereby append an azido group to the target protein in a single step. The azido protein retained full biol. activity. Furthermore, its azido group was available for chem. modification by Huisgen 1,3-dipolar azide-alkyne cycloaddition Thus, the mechanism of intein-mediated protein splicing provides the means to install a useful functional group at a specific site-the C terminus-of virtually any protein. In the experiment, the researchers used many compounds, for example, 2,5-Dioxopyrrolidin-1-yl 3′,6′-dihydroxy-3-oxo-3H-spiro[isobenzofuran-1,9′-xanthene]-5-carboxylate (cas: 92557-80-7Formula: C25H15NO9).
2,5-Dioxopyrrolidin-1-yl 3′,6′-dihydroxy-3-oxo-3H-spiro[isobenzofuran-1,9′-xanthene]-5-carboxylate (cas: 92557-80-7) belongs to benzofurans derivatives. Benzofuran derivatives have shown many biological activities, including antifungal and antimicrobial properties, and acting as antagonists of H3 receptors and angiotensin II. In nature, benzofurans have occupied an important role among the plant phenols & several pharmacologically active compounds.Formula: C25H15NO9
Referemce:
Benzofuran – Wikipedia,
Benzofuran | C8H6O – PubChem