3-Cresol purple

• CAT Number: I020870
• CAS Number: 2303-01-7
• Molecular Formula: C21H18O5S
• Molecular Weight: 382.43
• Purity: 98%
• Synonyms: 3-Cresol purple
• Solubility: Soluble in DMSO
• Appearance: Solid powder
• Storage: Dry, dark and at 0 - 4 C for short term (days to weeks) or -20 C for long term (months to years).
• IUPAC Name: 4-[3-(4-hydroxy-2-methylphenyl)-1,1-dioxo-2,1lambda6-benzoxathiol-3-yl]-3-methylphenol
• InChI: InChI=1S/C21H18O5S/c1-13-11-15(22)7-9-17(13)21(18-10-8-16(23)12-14(18)2)19-5-3-4-6-20(19)27(24,25)26-21/h3-12,22-23H,1-2H3
• InChIKey: OLQIKGSZDTXODA-UHFFFAOYSA-N
• SMILES: CC1=C(C=CC(=C1)O)C2(C3=CC=CC=C3S(=O)(=O)O2)C4=C(C=C(C=C4)O)C

3-Cresol purple（Cat No.:I020870）is a pH indicator commonly used in scientific research and laboratory applications. It changes color in response to shifts in pH, transitioning from yellow at a pH below 7 to purple at a pH above 8. It is often used in titrations, buffer solutions, and other acid-base reactions to visually monitor pH changes. Due to its sensitivity in the alkaline pH range, 3-cresol purple is particularly useful in experiments involving weak acids and bases. It is also employed in microbiological and environmental studies to monitor changes in pH in cultures or water samples.

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