Intermolecular hydrogen bonds in hetero-complexes of biologically active aromatic molecules probed by the methods of vibrational spectroscopy.
By the methods of vibrational spectroscopy (Infrared and Raman) the investigation of the hetero-association of biologically active aromatic compounds: flavin-mononucleotide (FMN), ethidium bromide (EB) and proflavine (PRF) was performed in aqueous solutions. It was shown that between the functional groups (CO and NH(2)) the intermolecular hydrogen bonds are formed in the hetero-complexes FMN-EB and FMN-PRF, additionally stabilizing these structures. An estimation of the enthalpy of Н-bonding obtained from experimental shifts of carbonyl vibrational frequencies has shown that the H-bonds do not dominate in the magnitude of experimentally measured total enthalpy of the hetero-association reactions. The main stabilization is likely due to intermolecular interactions of the molecules in these complexes and their interaction with water environment.
A.Ya. Usikov Institute of Radiophysics and Electronics, National Academy of Sciences of the Ukraine, 12 Acad. Proscura Str., Kharkiv 61085, Ukraine. max_evstigneev@mail.ru
M A
MA
Semenov
Iu N
IuN
Blyzniuk
T V
TV
Bolbukh
A V
AV
Shestopalova
M P
MP
Evstigneev
V Ya
VY
Maleev
D004996:Ethidium / Q000737:chemistry*; D005486:Flavin Mononucleotide / Q000737:chemistry*; D006841:Hydrocarbons, Aromatic / Q000737:chemistry*; D006860:Hydrogen Bonding; D008968:Molecular Conformation; D011370:Proflavine / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013816:Thermodynamics; D014732:Vibration
D006841:Hydrocarbons, Aromatic; D005486:Flavin Mononucleotide; D011370:Proflavine; D004996:Ethidium