Yasueda, Yuki et al. published their research in Chemistry Letters in 2015 | CAS: 92557-80-7

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 is a core structural unit found in many naturally occurring compounds with multidirectional biological activities. In nature, benzofurans have occupied an important role among the plant phenols & several pharmacologically active compounds.Synthetic Route of C25H15NO9

Biomembrane-embedded catalysts for membrane-associated protein labeling on red blood cells was written by Yasueda, Yuki;Tamura, Tomonori;Kuwara, Keiko;Takaoka, Yousuke;Hamachi, Itaru. And the article was included in Chemistry Letters in 2015.Synthetic Route of C25H15NO9 This article mentions the following:

Membrane proteins play crucial roles in fundamental biol. processes. Here, we propose a new chem. strategy to label and characterize membrane proteins on cell surface. In this study, 4-dimethylaminopyridine (DMAP) is embedded and concentrated on plasma membrane surface (biomembrane-embedded DMAP: BeD), allowing to selectively modify membrane proteins with synthetic probes such as a fluorophore and an affinity tag. We applied this strategy to human red blood cells, which demonstrated that membrane proteins such as PAS-1 and Band-3 were selectively labeled. 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: 92557-80-7Synthetic Route of 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 is a core structural unit found in many naturally occurring compounds with multidirectional biological activities. In nature, benzofurans have occupied an important role among the plant phenols & several pharmacologically active compounds.Synthetic Route of C25H15NO9

Referemce:
Benzofuran – Wikipedia,
Benzofuran | C8H6O – PubChem