right so today I want to talk about a
molecule which really did change a huge
amount of lives in fact we saved many
many lives over the years since its
introducing about it I think it's late
1967 something like that
in 1965 the age range of 15 to 44 three
people in every hundred thousand died
from asthma died from asthma if we go to
ten years later in 1975 that was down to
just under one person and now it's less
than 0.4 I think people per hundred
thousand is dying because of asthma so
what happened in that interim what
caused this great success and that
molecule is part of this here
it's called salbutamol and it's the
first it was the first inhaled asthma
drug and it it works by just dilating
all the bronchial your lungs so you can
get more air in you can use that air
much better here's the technical bit so
this is adrenaline we've all heard of
adrenaline let's look at it that way
it's always looks better there that so
we've got a nitrogen here here we've got
an oxygen and over here we've got two
oxygens and a this is a benzene ring so
the important part about adrenaline is
obviously part of the nervous system is
a neurotransmitter and there are various
different receptors around your body
that accept adrenaline or Noor
adrenaline and noradrenaline is just the
one with a methyl on the nitrogen as
well so they're both natural compounds
and these will either speed up your
heart they all constrict your blood
vessels
they'll constrict or relax the bronchial
your lungs because if you're being if
being chased by a line your heart need
heart needs to speed up your blood
vessels constrict to help blood pressure
to get to your muscles your
bronchodilators you're gonna need a lot
of oxygen getting away from that line we
can use these to help dilate that the
lungs essentially so allowing more air
air flow but because they're natural
compounds there there are mechanisms for
the removal of these from the receptor
sites and those mechanisms are very
quick so it wouldn't be a very
long-lasting drug at all and the key to
the removal of adrenaline or
noradrenaline from the receptor site is
the methylation of this oxygen atom here
so let's just put a methyl on there that
then is absorbed it's not active and it
gets recycled but that is a phenolic OAH
so what the inventors of salbutamol did
very cleverly was to realize that if
they put in an extra carbon between the
benzene ring and the this particular
oxygen it's still in the same kind of
place it can still act but now this Oh H
bond is much stronger it's not phenolic
anymore
it's benzylic as we're we technically
call it so now the methylation of this
is much much slower so it's in the
receptor longer and it allows the
bronchi to dilate and for you to be able
to breathe again so this really has
saved millions of lives this this
molecule it's done is a kind of aerosol
so it goes straight to the active site
it doesn't get so far into your system
is to act on the heart or the brain or
anything else and then just the PS do
the resistance to help selectivity and
bioavailability they just made the
methyl group on the end here just just
pick that one up into a t-butyl group so
subtly different and that made it more
specific to the beta to Adreno sector
and there are various different types of
Adreno sectors so this now is the
molecule salbutamol this molecule is the
active ingredient of your asthma drug