Midterm Flashcards
What are the electron donating groups (ED)?
CH3, NH2, OH, OCH3, CH2CH3, O-
What are the electron withdrawing groups?
NO2, NH3+, CN, CF3, X
What groups increase water solubility?
Ionizable groups, N and O
What groups decrease water solubility?
Aromatic groups, alkyl chains and rings (t-butyl, benzene, isopropyl)
How does log P (pi) affect water solubility?
pi>0.5 means lipophilic
pi
Where is aliphatic hydroxylation preferred?
Closer to the middle or on the carbon closest to the aromatic ring
What substituent position do ED groups prefer?
ED groups favour para
How do you decide if a 3 membered ring is cis or trans?
Look at if the groups are sticking out or into the paper.
What happens during N-dealkylation?
The alkyl group on the N is taken off and replaced with an H.
Where is aromatic hydroxylation preferred?
On the para group
What form of a drug is better absorbed?
Unionized
What is the minimum bio availability for oral drugs?
20%
What are Lipinski’s Rule of Fives?
To see if a drug can be absorbed orally:
Molecular weight
How do we want bulky groups in a cyclohexane ring system?
Bulky groups should be equatorial
Any wedge group will be “up”, any dash group will be “down”
What are some examples of non-depolarizing neuromuscular blockers?
d-turbocurarine and pancuronium
What are all neuromuscular blockers used for?
Muscle relaxation during surgery.
What are some examples of depolarizing neuromuscular blockers?
Nicotine, succinylcholine and decamethonium
What are the rules for the structure of a muscarinic agonist?
N+ is required for activity
Removing methyl groups reduces potency
No more than 5 large single bonded atoms long
One eth on R group substitution makes fairly potent, any more decreases
R group longer than 3 C’s can’t fit into receptor
What are some examples of muscarinic agonists? What are they used for?
Edrophonium-diagnostic test for myasthenias gravis
Neostigmine-anesthesia
Pyridostigmine-myasthenia gravis (reversibly alkylates)
Physostigmine-crosses BBB (reversibly alkylates)
How do you stop binding by AchE?
Delocalized electrons
Methyl is added one carbon away from the ring as a steric shield
How do competitive antagonists change the graphs?
Shift dose/response graph to the right. ED50 changes but max efficacy stays the same Affinity decreases (increase in KD)
How do non-competitive antagonists change the graphs?
Shift dose/response graph lower
ED50 stays the same but max efficacy lowers
Affinity stays the same (same KD)
What type of receptor is the epidermal growth factor receptor and what is it needed for?
Transmembrane receptor/enzyme
Needed for growth and differentiation of epithelial cells
How does the epidermal growth factor receptor (EGFR) work?
The receptor is the transmembrane portion, tyrosine kinase is the enzyme. Ligands are epidermal growth factor (EGF) or transforming growth factor alpha (TGFalpha).
The binding of ligands cause cause EGFR dimerization and tyrosine kinase activity, causing autophosphorylation of EGFR tyrosine residues. Causes several signal transduction cascades which results in DNA synthesis and cell proliferation.
How does effector protein G alpha s work?
Binds to adenylate cyclase which makes cAMP which binds to and activates protein kinase A (PKA). PKA then phosphorylates many target proteins and opens Ca channels to pump Ca into the endoplasmic reticulum and increase stores which amplifies the signal again to produce responses.
Phosphodiesterases hydrolyzes cAMP, stopping signal.
How does effector protein G alpha i work?
Inhibits adenylate cyclase and opens K channels (hyperpolarization) causing less excitability