7-Acid and bases

bronsted lowry acis

proton donors

bronsted lowry bases

proton acceptor

What kind of acids and bases are drugs

weak acids/ bases

Ka

[H+][A-]/[HA]

pka=

-logKa

henderson hasselbach

pH=pKa+log [conjugate base]/acid

when pH=pkA

[conjugate base]=[acid]

When are acids ionized

when pH is above the pKA

when are bases ionized

when the pH is below the pKa

pka+2 what is percent ionized acid

99

ph=pka+1 what is percent ionized acid

90

ph= pka-1 what is percent ionized acid

10% ionized

ph= pka-2 what is percent ionized acid

1

base ph= pka+2 what percent ionizing

1

base ph= pka+1 what percent ionized

10

base ph=pka-1 what percent ionizied

90

base pH= pka-2 what percent ionized

100

how are most drugs abosrbed

by passive diffusion

what from of drug is preferentially absorbed

un-ionized for

what can impact cellular penetration and accumulation

cell permiability

why is cellular penetration importanti

intracellular drug targets and compartments with differing pH

roles of intermolecular forces

physical properties like mp, solubility

biological system interactions like targets and metabolising enzymes

examples of IMF

ionic, ion dipole, cation-pi

are ionized or unionized forms more water soluble

ionized

what AA can have cation pi

arginine and lysine because of + charge

Alkyl Carboxylic acid pka

5

aryl carboxylic acid pka

5

phenol pka

10

sulfonamide pka

10

common acidic functional group

sulfonamide

phenol

carboxylic acid

why is resonance an impact on acid stregth?

has resonance, delocalization lowers the pkA

what do factors that stabilize base through spreading negative charge do

increase the strength of the acid and lower the pka

how do electronegative groups impact pka

lower the pka

what do electron donating groups do to pka

increase

arylamine pka / aniline

5

pka of aromatic amine/ pyridine

5p

pka of alkylamine

10

pka of cyclic alkylamine

10

fatcors increasing base strength

increased electron density around a basic atom

spread out positive charge in conjugate acid

stronger bases have what kind of pka

higher

what does charge delocalization do to pka

increases it, more basic

what do electronegative groups do to bases

lower pka, less basic

how does hybridization impact bases

higher s contribution increases attraction to nucleus

neutral functional grousp

amides, alkyl alcohols, ketones, ethers, esters, aldehydes

what could amides act as

either acids or bases

why isn’t amide nitrogen basic

lone e- pair delocalizes into carbonyl pi system and are not accessible from protnation