9-(2-carboxyethyl)-N-ethyl-6-(ethylamino)-2,7-dimethyl-3H-xanthen-3-iminium perchlorate

• ChemBase ID: 155868
• Molecular Formular: C22H27ClN2O7
• Molecular Mass: 466.91198
• Monoisotopic Mass: 466.15067889
• SMILES: CCNc1cc2c(cc1C)c(c1cc(/c(=[NH+]\CC)/cc1o2)C)CCC(=O)O.[O-][Cl](=O)(=O)=O
• Canonical SMILES: [O-][Cl](=O)(=O)=O.CCNc1cc2oc3c/c(=[NH+]/CC)/c(cc3c(c2cc1C)CCC(=O)O)C
• InChI: InChI=1S/C22H26N2O3.ClHO4/c1-5-23-18-11-20-16(9-13(18)3)15(7-8-22(25)26)17-10-14(4)19(24-6-2)12-21(17)27-20;2-1(3,4)5/h9-12,23H,5-8H2,1-4H3,(H,25,26);(H,2,3,4,5)
• InChIKey: YWLGQYDVSLBBTP-UHFFFAOYSA-N

NAMES AND DATABASE IDS

Names

• IUPAC name: 9-(2-carboxyethyl)-N-ethyl-6-(ethylamino)-2,7-dimethyl-3H-xanthen-3-iminium perchlorate
• IUPAC Traditional name: 9-(2-carboxyethyl)-N-ethyl-6-(ethylamino)-2,7-dimethylxanthen-3-iminium perchlorate
• Synonyms: Atto 520

Database IDs

• MDL Number: MFCD03456128
• PubChem SID: 24886114; 162250006
• PubChem CID: 16211363

CALCULATED PROPERTIES

• Acid pKa: 4.2782507
• H Acceptors: 4
• H Donor: 3
• LogD (pH = 5.5): 1.2212507
• LogD (pH = 7.4): 0.4466035
• Log P: 1.1980234
• Molar Refractivity: 123.0302 cm^3
• Polarizability: 40.942284 Å^3
• Polar Surface Area: 72.53 Å^2
• Rotatable Bonds: 6
• Lipinski's Rule of Five: true

PROPERTIES

Physical Property

• Fluorescence: λex 520 nm; λem 540 nm in 0.1 M phosphate pH 7.0

Safety Information

• German water hazard class: 3
• Personal Protective Equipment: Eyeshields, Gloves, type N95 (US), type P1 (EN143) respirator filter
• Storage Temperature: 2-8°C

Product Information

• Purity: ≥90.0% (HPCE/HPLC)
• Suitability: suitable for fluorescence
• Product Line: BioReagent
• Empirical Formula (Hill Notation): C22H27ClN2O7

DETAILS

Sigma Aldrich - 70706

Application
Atto fluorescent labels are designed for high sensitivity applications, including single-molecule detection. Atto labels have rigid structures that do not show any cis-trans isomerization. Thus these labels display exceptional intensity with minimal spectral shift on conjugation.Atto 520 shows a molar extinction of 110,000 and QY of 90% in water (95% in ethanol). Decay time is 3.6 ns.
Other Notes
Employed in confocal fluorescence microscopy to confirm formation of polymer nanoshells;1 using combined imaging and scanning fluorescence correlation spectroscopy to characterize microsecond emission fluctuation.2