Sulfonamides as a subject to study molecular interactions in crystals and solutions: sublimation, solubility, solvation, distribution and crystal structure

Int J Pharm. 2008 Feb 12;349(1-2):300-13. doi: 10.1016/j.ijpharm.2007.07.034. Epub 2007 Aug 2.

Abstract

Crystal structures of 4-amino-N-(4-chlorophenyl)-benzene-sulfonamide (IV), 4-amino-N-(2,3-dichlorophenyl)-benzene-sulfonamide (V), 4-amino-N-(3,4-dichlorophenyl)-benzene-sulfonamide (VI) and 4-amino-N-(2,5-dichlorophenyl)-benzene-sulfonamide (VII) were solved by X-ray diffraction method. Temperature dependencies of saturated vapour pressure and thermodynamic functions of sublimation process were calculated (IV: delta Gsub298=74.0 kJ mol(-1), delta Hsub298=134.1+/-1.2 kJ mol(-1), delta Ssub298=202+/-3 J mol(-1)K(-1); V: delta Gsub298=61.7 kJ mol(-1), delta Hsub298=141.1+/-0.7 kJ mol(-1), delta Ssub298=266+/-2 J mol(-1)K(-1); VI: delta Gsub298=85.8 kJ mol(-1), delta Hsub298=167.5+/-3.6 kJ mol(-1), delta Ssub298=274+/-8 J mol(-1)K(-1); VII: delta Gsub298=75.7 kJ mol(-1), delta Hsub298=155.4+/-1.6 kJ mol(-1), delta Ssub298=268+/-4 J mol(-1)K(-1)). Thermochemical parameters of fusion and evaporation processes for the compounds were obtained. Temperature dependencies of the solubility in water, n-octanol were measured. The thermodynamic functions of solubility and solvation processes were deduced. The transfer processes of the molecules from water to n-octanol were analysed by diagram method and main driven forces were established.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Algorithms
  • Calorimetry, Differential Scanning
  • Crystallization
  • Hydrogen Bonding
  • Models, Molecular
  • Molecular Conformation
  • Pharmaceutical Solutions
  • Solubility
  • Solvents
  • Sulfonamides / chemistry*
  • Temperature
  • Thermodynamics
  • X-Ray Diffraction

Substances

  • Pharmaceutical Solutions
  • Solvents
  • Sulfonamides