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Rose bengal

Rose bengal
Rosebengalskeletal.png
Names
IUPAC name
4,5,6,7-Tetrachloro-3',6'-dihydroxy-2',4',5',7'-tetraiodo-3H- spiro[isobenzofuran-1,9'-xanthen]-3-one
Other names
C.I. 45440
Identifiers
11121-48-5 YesY
3D model (Jmol) Interactive image
ChEMBL ChEMBL1160160 N
ECHA InfoCard 100.115.989
Properties
C20H4Cl4I4O5
Molar mass 973.67 g/mol
1,017.65 g/mol (sodium salt)
Pharmacology
S01JA02 (WHO)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YesYN ?)
Infobox references

Rose bengal (4,5,6,7-tetrachloro-2',4',5',7'-tetraiodofluorescein) is a stain. Its sodium salt is commonly used in eye drops to stain damaged conjunctival and corneal cells and thereby identify damage to the eye. The stain is also used in the preparation of Foraminifera for microscopic analysis, allowing the distinction between forms that were alive or dead at the time of collection.

A form of rose bengal is also being studied as a treatment for certain cancers and skin conditions. The cancer formulation of the drug, known as PV-10, is currently undergoing clinical trials for melanoma and breast cancer. The company also has formulated a drug based on rose bengal for the treatment of eczema and psoriasis; this drug, PH-10, is currently in clinical trials as well.

Rose bengal was originally prepared in 1882 by Ghnem, as an analogue of fluorescein. Its name derives from rose (flower) and Bengal (region); it is printed as rose bengal or Rose Bengal in the scientific literature.

Rose bengal is also used in synthetic chemistry to generate singlet oxygen from triplet oxygen. The singlet oxygen can then undergo a variety of useful reactions, particularly [2 + 2] cycloadditions with alkenes and similar systems.

Rose bengal can be used to form many derivatives that have important medical functions. One such derivative was created so to be sonosensitive but photoinsensitive, so that with a high intensity focused ultrasound, it could be used in the treatment of cancer. The derivative was formed by amidation of rose bengal, which turned off the fluorescent and photosensitive properties of rose bengal, leading to a usable compound, named in the study as RB2.

Salts of rose bengal include C20H4Cl4I4O5·2Na (CAS 632-69-9). This sodium salt is a dye, which has its own unique properties and uses.


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Wikipedia

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