Lecture 4 Flashcards
Most drugs belonging to the same pharmacologic class have……
certain structural features in common.
for example:
-a basic Nitrogen
-an aromatic ring
-an ester or amide group
-a hydroxyl group (phenolic or alcoholic)
-an aliphatic or alicyclic portion of the molecule
similar structural features of molecules permit what?
these functional groups to be oriented in a similar pattern in space
functional groups are important in _____ interactions.
different arrangements of functional groups allow for…..
functional groups are important in BINDING SITE interactions.
different arrangements allow for HIGHLY SPECIFIC binding
what are the structural requirements for narcotic analgesic activity?
-a basic nitrogen
-an aromatic ring
-a tetrasubstituted carbon
-a 2 carbon chain linking the tetrasubstituted carbon and the basic N
name 3 narcotic analgesics.
when something has “narcotic analgesic activity” that means it affects…..
morphine
methadone
meperidine
not only are similar structures important, but also their…..
ARRANGEMENT (ie: a 2 carbon chain linking the tetrasubstituted carbon to the basic N in narcotic analgesics)
true or false
methadone and meperidine possess the same pharmacological activity as morphine
TRUE – even though they look very different
morphine, methadone, and meperidine all produce their effects by…..
binding to opioid receptors
who is the “father of med chem”
what did he say
Paul Ehrlich
he coined the term “receptors” to explain structural similarities in molecules with similar biological activity
meperidine and methadone are ___ ___
synthetic analgesics
endogenous opioid agonists
endorphins and enkephalins
true or false
the naturally produced opioid agonists (endorphins and enkephalins) produce the same effect as opioids, but through a different mechanism
FALSE – they all produce their effect by binding to opioid receptors
broadly speaking, the term “receptor” refers to…..
a relatively SMALL region of a macromolecule which may be:
-an isolatable enzyme
-a structural and functional component of a cell membrane or
-a specific intracellular substance such as a protein or a nucleic acid
receptors, most of the time, are ____ molecules
PROTEIN
Explain how receptors are visualized and how a biological response is produced when interacting with a drug
specific regions of these macromolecules (receptors) are visualized as being oriented in space in such a way that permits their functional groups to interact with COMPLEMENTARY FUNCTIONAL GROUPS OF THE DRUG
this interaction initiates a CHANGE IN THE STRUCTURE AND FUNCTION OF THE RECEPTOR (macromolecule) THAT ULTIMATELY LEADS TO AN OBSERVABLE BIOLOGICAL RESPONSE
Most drugs produce their effects by a ______ mechanism
receptor mediated
as mentioned, most drugs produce their effects through a receptor mediated mechanism.
are their any exceptions to this?
YES, there are 3 exceptions
- general anesthetics
- osmotic diuretics
- antacids
explain how osmotic diuretics do NOT produce their effects via a receptor mediated mechanism
they simply produce an osmotic gradient in the renal tubules, promoting the elimination of water in the urine
explain how antacids do not produce their effects through a receptor mediated mechanism
through an acid-base neutralization of the hydrochloric acid found in the stomach
do antacids require absorption to produce their effects?
NO
explain how general anesthetics do not produce their effects via a receptor-mediated mechanism
it is a general signal – not through a receptor
true or false
in drug design, the goal is to design drugs that are selective as possible to their receptors
TRUE – this will limit side effects
this is bc there are a variety of receptors with similar structural requirements for their ligands in multiple organs and tissues throughout the body. Receptors for the same ligand are found in multiple tissues
true or false
the role of a medicinal chemist is to design drugs that will bind selectively to the desired receptors with low affinity, so that side effects will be minimal
FALSE – HIGH AFFINITY
Give a specific example that demonstrates the need for high specificity drug-receptor interactions
there is a new class of cancer drugs called protein kinase inhibitors.
protein kinases are everywhere throughout the body, so the drug has to be VERY SPECIFIC to its target in order to receive the desired effects, and not side effects and/or toxicity
