25dhb.gifJMOL view

Compound Name: 2,5-dihydroxybenzoic acid
Common Names: gentisic acid, DHB
IUPAC Name: 2,5-dihydroxybenzoic acid

CAS RN: 490-79-9
SMILES: O=C(O)c1cc(O)ccc1O

ChemSpider Permalink:

Molecular Formula: C7H6O4
Molecular Weight (average): 154.1201
Molecular Weight (monisotopic): 154.02661
Melting point: ~206°C (dec)
LogP (ACD v5.0 logD calculated [3]): 1.56 +/-0.26
pKa (ACD v5.0 pKa calculated): 3.01 +/-0.10
Proton Affinity [2]: 204.4 +/-0.17 kcal/mol
Vapor pressure (ACD calculated): 2.38E-07 mmHg at 25°C

Spectral Information:
IR spectrum ATR 1cm-1 resolution
UV spectrum 1 nm resolution in methanol
UV spectrum 1 nm resolution in acetonitrile
SS-UV spectrum 1 nm resolution solid state diffuse reflectance measurements
337nm MALDI-TOF spectrum Positive ion spectrum from Bruker Reflex III
355nm MALDI-TOF spectrum Positive ion spectrum from Bruker Ultraflex TOF/TOF
355nm MALDI-TOF spectrum Negative ion spectrum from Bruker Ultraflex TOF/TOF
Optical images of DHB.pdf Edmund Scientific Resolution target with 100 lines/mm

Sample Info:
Aldrich 98% PN: 14935-7 (lot #: 11008DU)

Purification Information:
Procedure to recrystallize DHB from water.

A reference detailing the use of DHB as a MALDI matrix [1].

[1] Strupat, K.; Karas, M.; Hillenkamp, F., 2,5-Dihydroxybenzoic acid: a new matrix for laser desorption-ionization mass spectrometry, International Journal of Mass Spectrometry and Ion Processes, 111, 89-102, (1991).
[2] Mirza, S.P.; Raju, N.P.; Vairamani, M., Estimation of the Proton Affinity Values of Fifteen MALDI Matrices under Electrospray Ionization Conditions using the Kinetic Method, J. Amer. Soc. Mass Spectrom., 2004, 15, 431-5, DOI: http://dx.doi.org/10.1016/j.jasms.2003.12.001
[3] A.A. Petrauskas and E.A. Kolovanov, ACD/Log P method description, Perspectives in Drug Discovery and Design, 19, 99–116, 2000.