Calculate Physicochemical Properties

• Gain insights into structure-property relationships
• Understand and modify the pharmacokinetic profile of lead compounds
  • Good/bad indicators for Lipinksi’s rule of 5 and lead-likeness
• Identify structural fragments responsible for toxicity
• Modify sets of structures with the interactive optimization tool
  • Generate libraries of analogs with substituent modifications based on an optimal property profile
  • Sort, filter, and prioritize hundreds of structural analogs according to your desired property profile
  • Create and use custom fragment libraries
  • Target synthetically accessible fragments with the built-in retrosynthesis tool

• Calculate quantitative solubility in pure (unbuffered) water at 25°C
• Predict qualitative solubility at pH 7.4—compounds categorized from highly soluble to insoluble
  • GALAS (Global, Adjusted Locally According to Similarity) algorithm
  • Display of 5 most similar structures from the training set with experimental values
• Estimate intrinsic solubility—logS₀
  • Predictions based on a training set of >6800 compounds and a GALAS algorithm
  • Reliability value and up to 5 most similar structures from the training set provided with experimental data
• Predict pH-dependent aqueous solubility—logS
  • Solubility at physiological pH values of interest (pH 1.7, 4.6, 6.5, 7.4, 8.0)
  • Plot of predicted pH versus solubility
• Train the model with experimental values

• Estimate the boiling point of organic compounds as a function of pressure
• Predict the vapor pressure as a function of temperature
• Estimate the enthalpy of vaporization at the boiling point
• Estimate flash point at the temperature unit of your choice
• View results in a table or graphical plot

• Predict logP—choose from three prediction algorithms:
  • Classic
  • GALAS (Global, Adjusted Locally According to Similarity)
  • Consensus logP based on the other two models.
• Detailed calculation protocol lists all contributing functional groups, carbon atoms, and interactions through aliphatic, aromatic, and vinylic systems (Classic)
  • Click protocol entry to highlight the corresponding entity on the structure
• Color highlighting of the molecule to highlight hydrophilic/lipophilic substructures (GALAS)
• Train the model with experimental values to improve predictions for proprietary chemical space
  • Create and select different training libraries for calculations, or switch to the built-in algorithm

Learn more about ACD/LogP

LogD predictions are based on the logP and pK_a models of PhysChem Suite

• Select from a variety of logP and pK_a algorithms (default: logP Consensus, pK_a Classic)
• View logD calculation results by pH
  • Physiologically relevant values (1.7 , 4.6 , 6.5, 7.4 , 8.0 )
  • Click and drag across the plot (logD vs pH) for logD at a pH value of interest
  • Add/remove predictions at a specific pH value
• Train the model with experimental values of logP and pK_a to improve predictions for proprietary chemical space
  • Create and select different training libraries for calculations, or switch to the built-in algorithm

Learn more about ACD/LogD

• Calculate the acid dissociation constant (pK_a) under standard conditions (25°C, zero ionic strength) in aqueous solution for every ionizable group
• Choose from two different algorithms: ACD/pKa Classic (default calculator) and GALAS
• Information about each ionization process (dissociation reaction) for all stages of ionization
• Color-coding of ionizable groups: red = acidic, blue = basic, purple = amphoteric ionization centers; color intensity indicates acid/base strength.
• Calculation of the strongest acid and base dissociation constants
• Reliability range (in ±log units) for calculated pKa values
• Detailed calculation protocol for each predicted ionization (referred to as dissociation stage)
  • Hover on a dissociation stage to see the related ionizable center highlighted on the structure
  • Click structure fragment to see it highlighted on the structure
• Train the algorithm with experimental data

Learn more about ACD/pK_a

• Display of the percentage contribution of individual ionization microstages to the final pK_a
• View calculated pK_a values as a function of pH in interactive plots (pH 0-14) and tables (select pH values including the physiologically relevant values 1.7, 4.6 , 6.5, 7.4)
  • Net charge vs. pH
  • Click and drag slider on the plot to see the ionic forms present at the pH of interest
  • See the fraction of all ionic forms present at a pH of interest
  • Protonation state vs. pH
  • Click on the protonation state label to display/hide its curve on the plot
  • Ionogenic group state vs. pH

• Calculate substituent-specific parameters for selected fragments of the molecule in aqueous solution, at zero ionic strength and 25°C
  • Electronic substituent constant (Hammett)
  • Steric constants (molar volume, molar refractivity)
  • Hydrophobic constant (Hansch Pi)
• High accuracy—typical calculation accuracy of ±0.05
• Internal database contains >850 substituents and >3000 carefully derived experimental electronic constants

• Density
• Freely Rotatable Bonds
• H-Bond Donors and Acceptors
• Index of Refraction
• Molar Refractivity
• Molar Volume
• Molecular Weight
• Parachor
• Polar Surface Area
• Polarizability
• Rule-of-5
• Surface Tension