2 The Role of Carbon in Drug Molecules Flashcards
Hydrocarbons - what is the trend in boiling point for increasing molecular weight?
Boiling point increases as molecular weight increases.
What are the two conformations of saturated hydrocarbons?
Eclipsed and Staggered
Which conformation of saturated hydrocarbons is favoured?
Staggered - H atoms are far enough away from each other
What bond type causes torsional strain?
Eclipsed bonds
What causes Van der Waals strain (steric strain?
Atoms being too close together
What causes angle strain?
Distortion of bond angles from typical values
What does a positive substituent hydrophobicity constant show?
Substituents are more hydrophobic than H
What does a negative substituent hydrophobicity constant show?
Substituents are less hydrophobic than H
How can we calculate C-C bong angles, assuming rings are flat?
C-C bond angle = (180(n-2))/n
when n=number of C-C bonds in the constituent
What does the substituent hydrophibicity constant measure?
The hydrophibicity (hydrophobic-ness) compared to hydrogen
What is the formula for substituent hyrophibicity constant?
pi x=logPx-logPH
pi=constant
PH=partition coefficent unsubed compound
How can we find the hydrophobicity constant of benzene from chlorobenzene?
Subtract teh hydrophibicity constant of Cl atom from chlorobenzene
What are the two forms of the inductive effect?
Negative Inductive effect (-I)
Posittive inductive effect (+I)
Electron withdrawing nature - ____ Inductive Effect
Negative inductive effect
Electron donating nature - ____ Inductive Effect
Positive Inductive Effect
