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A crash course in organic chemistry

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    I'd like you to ask yourself,
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    what do you feel when you hear
    the words "organic chemistry?"
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    What comes to mind?
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    There is a course offered
    at nearly every university,
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    and it's called Organic Chemistry,
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    and it is a grueling, heavy
    introduction to the subject,
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    a flood of content
    that overwhelms students,
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    and you have to ace it if you want
    to become a doctor or a dentist
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    or a veterinarian.
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    And that is why so many students
    perceive this science like this ...
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    as an obstacle in their path,
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    and they fear it and they hate it
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    and they call it a weed-out course.
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    What a cruel thing for a subject
    to do to young people,
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    weed them out.
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    And this perception spread
    beyond college campuses long ago.
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    There is a universal anxiety
    about these two words.
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    I happen to love this science,
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    and I think this position
    in which we have placed it
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    is inexcusable.
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    It's not good for science
    and it's not good for society,
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    and I don't think it has to be this way.
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    And I don't mean that this class
    should be easier. It shouldn't.
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    But your perception of these two words
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    should not be defined
    by the experiences of premed students
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    who frankly are going through
    a very anxious time of their lives.
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    So I'm here today because I believe
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    that a basic knowledge
    of organic chemistry is valuable,
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    and I think that it can be made
    accessible to everybody,
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    and I'd like to prove that to you today.
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    Would you let me try?
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    Audience: Yeah!
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    Jakob Magolan: All right, let's go for it.
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    (Laughter)
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    Here I have one of these
    overpriced EpiPens.
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    Inside it is a drug called epinephrine.
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    Epinephrine can restart
    the beat of my heart,
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    or it could stop a life-threatening
    allergic reaction.
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    An injection of this
    right here will do it.
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    It would be like turning
    the ignition switch
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    in my body's flight-or-flight machinery.
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    My heart rate, my blood pressure would
    go up so blood could rush to my muscles.
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    My pupils would dilate.
    I would feel a wave of strength.
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    Epinephrine has been the difference
    between life and death for many people.
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    This is like a little miracle
    that you can hold in your fingers.
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    Here is the chemical structure
    of epinephrine.
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    This is what organic chemistry looks like.
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    It looks like lines and letters ...
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    No meaning to most people.
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    I'd like to show you what I see
    when I look at that picture.
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    I see a physical object
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    that has depth and rotating parts,
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    and it's moving.
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    We call this a compound or a molecule,
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    and it is 26 atoms that are stitched
    together by atomic bonds.
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    The unique arrangement of these atoms
    gives epinephrine its identity,
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    but nobody has ever
    actually seen one of these,
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    because they're very small,
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    so we're going to call this
    an artistic impression,
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    and I want to explain to you
    how small this is.
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    In here, I have less than
    half a milligram dissolved in water.
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    It's the mass of a grain of sand.
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    The number of epinephrine
    molecules in here is one quintillion.
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    That's 18 zeroes.
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    That number is hard to visualize.
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    Seven billion of us on this planet?
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    Maybe 400 billion stars in our galaxy?
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    You're not even close.
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    If you wanted to get
    into the right ballpark,
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    you'd have to imagine every grain of sand
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    on every beach,
    under all the oceans and lakes,
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    and then shrink them all
    so they fit in here.
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    Epinephrine is so small
    we will never see it,
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    not through any microscope ever,
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    but we know what it looks like,
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    because it shows itself
    through some sophisticated machines
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    with fancy names
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    like "nuclear magnetic
    resonance spectrometers."
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    So visible or not, we know
    this molecule very well.
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    We know it is made
    of four different types of atoms,
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    hydrogen, carbon, oxygen and nitrogen.
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    These are the colors
    we typically use for them.
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    Everything in our universe
    is made of little spheres
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    that we call atoms.
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    There's about a hundred
    of these basic ingredients,
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    and they're all made
    from three smaller particles:
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    protons, neutrons, electrons.
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    We arrange these atoms
    into this familiar table.
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    We give them each a name and a number.
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    But life as we know it
    doesn't need all of these,
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    just a smaller subset, just these.
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    And there are four atoms in particular
    that stand apart from the rest
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    as the main building blocks of life,
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    and they are the same ones
    that are found in epinephrine:
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    hydrogen, carbon, nitrogen and oxygen.
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    Now what I tell you next
    is the most important part.
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    When these atoms
    connect to form molecules,
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    they follow a set of rules.
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    Hydrogen makes one bond,
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    oxygen always makes two,
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    nitrogen makes three
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    and carbon makes four.
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    That's it.
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    HONC -- one, two, three, four.
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    If you can count to four
    and you can misspell the word "honk,"
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    you're going to remember this
    for the rest of your lives.
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    (Laughter)
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    Now here I have four bowls
    with these ingredients.
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    We can use these to build molecules.
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    Let's start with epinephrine.
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    Now, these bonds between atoms,
    they're made of electrons.
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    Atoms use electrons like arms
    to reach out and hold their neighbors.
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    Two electrons in each bond,
    like a handshake,
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    and like a handshake,
    they are not permanent.
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    They can let go of one atom
    and grab another.
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    That's what we call a chemical reaction,
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    when atoms exchange partners
    and make new molecules.
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    The backbone of epinephrine
    is made mostly of carbon atoms,
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    and that's common.
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    Carbon is life's favorite
    structural building material,
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    because it makes
    a good number of handshakes
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    with just the right grip strength.
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    That's why we define organic chemistry
    as the study of carbon molecules.
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    Now, if we build the smallest molecules
    we can think of that follow our rules,
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    they highlight our rules,
    and they have familiar names:
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    water, ammonia, and methane,
    H20 and NH3 and CH4.
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    The words "hydrogen,"
    "oxygen" and "nitrogen" --
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    we use the same words
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    to name these three molecules
    that have two atoms each.
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    They still follow the rules,
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    because they have one, two
    and three bonds between them.
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    That's why oxygen gets called O2.
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    I can show you combustion.
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    Here's carbon dioxide, CO2.
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    Above it, let's place water and oxygen,
    and beside it, some flammable fuels.
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    These fuels are made
    of just hydrogen and carbon.
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    That's why we call them hydrocarbons.
    We're very creative.
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    (Laughter)
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    So when these crash
    into molecules of oxygen,
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    as they do in your engine
    or in your barbecues,
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    they release energy and they reassemble,
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    and every carbon atom
    ends up at the center of a CO2 molecule,
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    holding on to two oxygens,
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    and all the hydrogens end up
    as parts of waters,
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    and everybody follows the rules.
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    They are not optional,
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    and they're not optional
    for bigger molecules either,
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    like these three.
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    This is our favorite vitamin
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    sitting next to our favorite drug,
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    (Laughter)
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    and morphine is one of the most
    important stories in medical history.
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    It marks medicine's first
    real triumph over physical pain,
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    and every molecule has a story,
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    and they are all published.
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    They're written by scientists,
    and they're read by other scientists,
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    so we have handy representations
    to do this quickly on paper,
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    and I need to teach you how to do that.
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    So we lay epinephrine flat on a page,
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    and then we replace all the spheres
    with simple letters,
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    and then the bonds
    that lie in the plane of the page,
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    they just become regular lines,
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    and the bonds that point
    forwards and backwards,
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    they become little triangles,
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    either solid or dashed to indicate depth.
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    We don't actually draw these carbons.
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    We save time by just hiding them.
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    They're represented
    by corners between the bonds,
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    and we also hide every hydrogen
    that's bonded to a carbon.
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    We know they're there
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    whenever a carbon is showing us
    any fewer than four bonds.
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    The last thing that's done
    is the bonds between OH and NH.
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    We just get rid of those
    to make it cleaner,
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    and that's all there is to it.
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    This is the professional way
    to draw molecules.
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    This is what you see on Wikipedia pages.
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    It takes a little bit of practice,
    but I think everyone here could do it,
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    but for today, this is epinephrine.
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    This is also called adrenaline.
    They're one and the same.
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    It's made by your adrenal glands.
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    You have this molecule mixed
    into your body right now.
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    It's a natural molecule.
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    This EpiPen would just give you
    a quick quintillion more of them.
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    (Laughter)
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    We can extract epinephrine
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    from the adrenal glands
    of sheep or cattle,
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    but that's not
    where this stuff comes from.
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    We make this epinephrine in a factory
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    by stitching together smaller molecules
    that come mostly from petroleum.
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    And this is 100% synthetic.
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    And that word, "synthetic,"
    makes some of us uncomfortable.
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    It's not like the word "natural,"
    which makes us feel safe.
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    But these two molecules,
    they cannot be distinguished.
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    We're not talking about two cars
    that are coming off an assembly line here.
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    A car can have a scratch on it,
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    and you can't scratch an atom.
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    These two are identical in a surreal,
    almost mathematical sense.
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    At this atomic scale,
    math practically touches reality.
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    And a molecule of epinephrine ...
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    it has no memory of its origin.
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    It just is what it is,
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    and once you have it,
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    the words "natural" and "synthetic,"
    they don't matter,
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    and nature synthesizes
    this molecule just like we do,
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    except nature is much better
    at this than we are.
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    Before there was life on Earth,
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    all the molecules were small, simple:
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    carbon dioxide, water, nitrogen,
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    just simple things.
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    The emergence of life changed that.
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    Life brought biosynthetic factories
    that are powered by sunlight,
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    and inside these factories,
    small molecules crash into each other
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    and become large ones:
    carbohydrates, proteins, nucleic acids,
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    multitudes of spectacular creations.
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    Nature is the original organic chemist,
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    and her construction also fills our sky
    with the oxygen gas we breathe,
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    this high-energy oxygen.
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    All of these molecules are infused
    with the energy of the Sun.
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    They store it like batteries.
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    So nature is made of chemicals.
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    Maybe you guys can help me
    to reclaim this word, "chemical,"
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    because it has been stolen from us.
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    It doesn't mean toxic
    and it doesn't mean harmful
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    and it doesn't mean man-made or unnatural.
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    It just means "stuff," OK?
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    (Laughter)
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    You can't have
    chemical-free lump charcoal.
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    That is ridiculous.
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    (Laughter)
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    And I'd like to do one more word.
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    The word "natural" doesn't mean "safe,"
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    and you all know that.
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    Plenty of nature's
    chemicals are quite toxic,
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    and others are delicious,
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    and some are both ...
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    (Laughter)
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    toxic and delicious.
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    The only way to tell
    whether something is harmful
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    is to test it,
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    and I don't mean you guys.
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    Professional toxicologists:
    we have these people.
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    They're well-trained,
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    and you should trust them like I do.
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    So nature's molecules are everywhere,
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    including the ones that have decomposed
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    into these black mixtures
    that we call petroleum.
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    We refine these molecules.
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    There's nothing unnatural about them.
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    We purify them.
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    Now, our dependence on them for energy --
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    that means that every one of those carbons
    gets converted into a molecule of CO2.
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    That's a greenhouse gas
    that is messing up our climate.
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    Maybe knowing this chemistry
    will make that reality easier to accept
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    for some people, I don't know,
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    but these molecules
    are not just fossil fuels.
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    They're also the cheapest
    available raw materials
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    for doing something
    that we call synthesis.
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    We're using them like pieces of LEGO.
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    We have learned how to connect them
    or break them apart with great control.
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    I have done a lot of this myself,
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    and I still think it's amazing
    it's even possible.
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    What we do is kind of like assembling LEGO
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    by dumping boxes of it
    into washing machines,
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    but it works.
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    We can make molecules that are
    exact copies of nature, like epinephrine,
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    or we can make creations of our own
    from scratch, like these two.
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    One of these eases the symptoms
    of multiple sclerosis;
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    the other one cures a type of blood cancer
    that we call T-cell lymphoma.
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    A molecule with the right size and shape,
    it's like a key in a lock,
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    and when it fits, it interferes
    with the chemistry of a disease.
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    That's how drugs work.
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    Natural or synthetic,
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    they're all just molecules that happen
    to fit snugly somewhere important.
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    But nature is much better
    at making them than we are,
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    so hers look more impressive than ours,
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    like this one.
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    This is called vancomycin.
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    She gave this majestic beast
    two chlorine atoms
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    to wear like a pair of earrings.
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    We found vancomycin in a puddle of mud
    in a jungle in Borneo in 1953.
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    It's made by a bacteria.
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    We can't synthesize this
    cost-efficiently in a lab.
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    It's too complicated for us, but we
    can harvest it from its natural source,
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    and we do, because this is
    one of our most powerful antibiotics,
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    and new molecules are reported
    in our literature every day.
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    We make them or we find them
    in every corner of this planet.
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    And that's where drugs come from,
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    and that's why your doctors
    have amazing powers
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    (Laughter)
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    to cure deadly infections
    and everything else.
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    Being a physician today
    is like being a knight in shining armor.
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    They fight battles
    with courage and composure,
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    but also with good equipment.
  • 14:07 - 14:11
    So let's not forget the role
    of the blacksmith in this picture,
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    because without the blacksmith,
    things would look a little different ...
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    (Laughter)
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    But this science is bigger than medicine.
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    It is oils and solvents and flavors,
    fabrics, all plastics,
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    the cushions that
    you're sitting on right now --
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    they're all manufactured,
    and they're mostly carbon,
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    so that makes all of it organic chemistry.
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    This is a rich science.
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    I left out a lot today:
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    phosphorus and sulfur and the other atoms,
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    and why they all bond the way they do,
  • 14:42 - 14:43
    and symmetry
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    and non-bonding electrons,
  • 14:45 - 14:47
    and atoms that are charged,
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    and reactions and their mechanisms,
    and it goes on and on and on,
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    and synthesis takes a long time to learn.
  • 14:52 - 14:55
    But I didn't come here to teach
    you guys organic chemistry --
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    I just wanted to show it to you,
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    and I had a lot of help with that today
    from a young man named Weston Durland,
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    and you've already seen him.
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    He's an undergraduate
    student in chemistry,
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    and he also happens to be
    pretty good with computer graphics.
  • 15:10 - 15:12
    (Laughter)
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    So Weston designed
    all the moving molecules
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    that you saw today.
  • 15:17 - 15:20
    He and I wanted to demonstrate
    through the use of graphics like these
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    to help someone talk
    about this intricate science.
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    But our main goal was just to show you
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    that organic chemistry
    is not something to be afraid of.
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    It is, at its core, a window
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    through which the beauty
    of the natural world looks richer.
  • 15:36 - 15:38
    Thank you.
  • 15:38 - 15:41
    (Applause)
Title:
A crash course in organic chemistry
Speaker:
Jakob Magolan
Description:

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Video Language:
English
Team:
closed TED
Project:
TEDTalks
Duration:
15:53

English subtitles

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