Category Archives: Pre-meds need to pass orgo

Why Pre-meds hate Organic Chemistry before they even begin the course

I figure that I had to work somewhere between 8 and 15 hours at the minimum wage to buy my organic chemistry textbook.  The text was English and Cassidy “Principles of Organic Chemistry” 2nd Edition.  The time was the summer of 1958 just before my junior year.  I worked at a cash register checking out groceries in beautiful Acme Markets making the princely sum of $1.00 perhour (the minimum wage then).  Social Security took .03 of the dollar, and there were union dues to pay (I don’t  recall just how much, but it’s unlikely that I’ve have received even that without the union).

I’m not sure what English and Cassidy cost, but I did try to find out by calling McGraw Hill (the publisher) to see if they knew but they didn’t. Being a packrat I still have a few chemistry books from that era, also published by McGraw Hill — Eliel “Stereochemistry of Carbon Compounds” bought in ’62 price $15.00 and “Molecular Vibrations” by E. B. Wilson (of Pauling and Wilson) for $10.00. So the more mass market English and Cassidy probably cost less — I’m guessing $8.00.

I always like to see what books profs think are best for their students, and one elite woman’s college in the area is using “Organic Chemistry” by John McMurray. Students are asked to buy it along with a study guide for a total of $238 (at the college bookstore).  Wow !  Currently the minimum wage is $7.25/hour with a social security and medicare cut out of 7.65% bringing the net down to 6.70.  That’s about 36 hours of work.

It gets worse.  There is a new edition of the work (the $238 book came out in ’07), which Amazon will sell you (along with study guide) for a mere $337.51 or just 50 hours work. This appeared 4 years after the $238 work.  Has that much changed?  Is it just another way to gouge the student?

Now to be fair,  English and Cassidy had 442 pages of text and answers to about 25% of the exercises in another 12.  The $238 version of McMurray is much larger so it has more information per page.  In addition it has far more pages, 1376 in the text and 912 in the study guide.  Pagewise that’s a ratio of (1376 + 912)/455 — about 5.  This is about the ratio of the 36 hours of work required today to the 8 required in ’58.

More importantly, the graphics in English and Cassidy were essentially nonexistent, while those in today’s books are excellent, multiple and certainly make thinking about organic chemistry easier. My wife says that graphics are difficult to print, but it seems to me that they are now so universal, that there must be some economy of scale in producing them.  Does anyone know?

A college football coach said that his job was to win just enough to make the alumni sullen but not mutinous.  This may explain a lot of the hostility going both ways between the grad students acting as teaching assistants and lab instructors, and their impoverished charges.

Some facts and principles to know cold while learning organic chemistry

 

Somehow this blog got mentioned in a list of the 25 best sites for college chemistry majors (http://www.onlinedegrees.org/25-best-chemistry-blogs-for-college-students/).  Classes are just starting up, so I want to get this out quickly.  It isn’t graven in stone, and additions will be put in from time to time, along with date they were put in, so you don’t have to read through the whole thing to find the new stuff.
It is impossible to learn organic chemistry by memorizing it.  First,  there is just too much of it.  Second, it isn’t hard to make (and be tested on) an organic molecule that has never been made before.  So it is crucial to be able to apply principles to new situations (which is one reason why I think anyone thinking of becoming an MD should be able to do it). 
Nonetheless, a certain number of facts and principles simply must be learned (memorized if you will) and become second nature.   Get them down cold and you’ll be surprised how much easier organic chemistry becomes.  
 I’m presently rereading the first 1000 pages of Clayden, Greeves, Warren and Wothers “Organic Chemistry” Oxford University Press 2001, so this post will be a work in progress. Additions will be surrounded by the date they’re added.   Clayden et. al. is  a great book and full of principles and explanations for them (as far as they can be given).  One of  the few shortcomings of  Clayden’s book  is that it never supplies these  princples about the transition metals, so you are just given an arbitrary collection of facts about them that you must know.  If you don’t like this, be warned — you’ll find a lot of this sort of thing in medical school — because such principles aren’t available even to the most knowledgeable doc.
Another site to look at is  http://masterorganicchemistry.wordpress.com/  — it didn’t make the list of 25, but I think it’s quite good. 
Here goes:
The more electronegative an atom is the lower in energy its atomic orbitals are.  Why? Across a row electronegativity correlates with charge of the nucleus, so more highly charged nuclei (to the right) are more electronegative.  The more electronegative an atom is, the closer the electron orbital is to the nucleus, this is of lower energy because there is less separation of positive and negative charges.  

(4 Sep ’10) Memorizing numbers is hard, but the following is easy.  The first row of the periodic table will soon become your friend  Li Be B C N O F Ne.  The electronegativities start at Li 1.0 and pretty go up by .5 as you go across the row.  C is 2.5 which explains why the bonds it forms with the other elements are covalent — they’re just not that far apart in electronegativity.  Recall the numbers, and you’ll be able to assign the relative polarity {which atom is relatively positive and which atom is relatively negative in each bond} and how covalent the bond is to any other element down farther in the table, once you look up its electronegativty.  Try it with Silicon, Magnesium  etc. etc.  (4 Sep ’10)

S orbitals get closer to the nucleus than p orbitals (which actually have a node at the nucleus), so they are of lower energy.  So sp hybridized orbitals are lower in energy than sp2 than sp3.

Carbanions are more stable the more s character the orbital the two electrons are in (makes sense electrostatically, and negative electrons are on average closer to the nucleus in an s orbital than a p orbital).  Clayden p. 214.

Since alkyl groups are electron donating (I’m not sure why) primary carbanions are more stable than secondary carbanions, and secondary carbanions are more stable than tertiary carbanions.   Just the reverse holds for carbocations.

So the pKa’s are   
methane is 48
benzene is 43
acetylene is 25 (because the anion on an sp hybridized carbon is more stable)

(26 Sep ’10 )Substituted double bonds are more stable Clayden p. 489.  You don’t have to know the reason, but it is interesting nonetheless.  It’s something we used to call hyperconjugation. Clayden has a nice discussion here (although in different terms) — interaction of an antibonding pi* orbital with filled orbitals of parallel C-H and C-C bonds 

(28 Sep ’10) More substituted double bonds are also more nucleophilic than less substituted ones  Clayden 507. This is because the energy level of the  highest HOMO is increased by the electron donating effects of the attached alkyl groups.  I’m not sure why this makes them more stable, in fact I’d think raising an energy level would make a molecule less stable.

Nonbonding electrons in molecules (say NH3) are ALWAYS higher in energy than bonding electrons Clayden p.118
Electrophiles have either (1) an empty atomic orbital (2) a low-energy antibonding orbital.  This is why Br2 is an electrophile despite those 8 electrons around each atom — there is a low lying antibonding orbital.  Why is the antibonding orbital in Br2 of such low energy?  Because the Br-Br sigma bond is weak.   The C-C bond is strong so its antibonding orbital is of higher energy.   Why? Because molecular orbital theory tells us that the antibonding molecular orbital must go up in energy by at least as much as the bonding molecular orbital goes down in energy (all this is relative to the energy of the two unbonded atomic orbitals).    This is only true if we’re speaking of identical atoms, because here the atomic orbitals are of the same energy.  

Clayden p. 119 The most important antibonding orbital is the pi* orbital — is doesn’t have anything in it — rather Zenlike don’t you think?  As Clayden notes, a step on a staircase is still there whether or not anyone is stepping on it. Cute !

Hard nucleophile — these have high charge density because they are low in the periodic table where orbitals are small and close to the nucleus and not screened by other electrons.  Hard nucleophiles tend to go where the positive charge is greatest.  Examples are anions like F-, OH-, RO-, SO4–, Cl- , NH3, RMgBr, RLi  Clayden 237, 411.

Soft nucleophile — these have low charge density.  They react by putting their electrons into low level antibonding orbitals.  Examples are I-, RS-, C=C bonds.  Given the choice between a dipolar bond (like the carbonyl group) and a double bond — they choose the double bond.  

Electrophiles can be categorized the same way — H+ is as hard as they come, Br2 is soft .  The carbon of a C=0 group is hard Clayden 238

Hard nucleophiles tend to react with hard electrophiles, soft with soft (I’m not clear why this is true, but it is).  This is why H20 reacts with C=O in alpha beta unsaturated compounds, while Br2 reacts with the double bond.  Clayden 238

25 Sep ’10 Mnemonics: Med students love them, and the more scatological the better — Never Lower Tillie’s Pants, Mother Might Come Home — for the 8 bones of the wrist.  I’ll put in a few that I’ve found helpful.    The neurologist in me compels me to tell you that scatological stuff is easier to remember because it has an emotional kick.  Where were you and what were you doing when you first heard about 9/11?
I never could keep enantiomer and diastereomer straight.  Enantiomers are mirror images of each other, diastereomers are not.  English speakers will find it far easier to pronounce MIrrorEnantiomer than MirrorDiastereomer.  The rest of you are on your own.
R and S in the Cahn Ingold Prelog system:   The numbers 1, 2 and 3 are in a circle, with 1 on top.  The configuration is R if 2 appears to the Right of the 1 in a circle.

Some basic pharmacology for the college student

I have no idea who reads Chemiotics II, or what their backgrounds are.  I do know that the people who comment are quite sophisticated in molecular biology, protein chemistry etc. etc. For some reason, Chemiotics II recently made the following list:  http://www.onlinedegrees.org/25-best-chemistry-blogs-for-college-students/  I don’t want to leave anyone behind, and I certainly didn’t know any of this stuff in college (’56 – ’60), much of it bering unknown, hence the reason for this post. 

Most of the drugs docs use work by binding to proteins (which I assume you know a reasonable amount about) altering their structure and function in some way.  Here are a few examples of interest to premeds (and hopefully the rest of you).

Curare is the generic term for poisons used by tribes of neuropharmacologists in South America on their arrows to kill prey.  D-tubocurarine (D-Tc) is one such curare.  It has a beautiful structure which the budding organic chemists among you should look up.  D-Tc works by binding to the protein receptor for acetyl choline in muscle and preventing its action (which is to conduct sodium ions into the muscle cell so it can contract).  Prey can’t move (or breathe).  D-tc is a classic example of an antagonist drug.  It blocks the normal effect of the normal ligand of the protein.    One true story about curare is just too good to pass up. 

Interns don’t get much sleep.  On my 3 month surgery rotation back in ’67 it was 36 hours on and 12 off, but to get a weekend off, call was bunched so that in one 7 day stretch it was 5 nights on 2 nights off making 24/168 hours off call.  Most nights we got 3 – 4 hours of crummy sleep. My wife, knowing conversation was hopeless, took the kids to her parents that week.   According to legend, Mary Walker was one such intern, who in 1934 fell asleep during a lecture on myasthenia gravis (a disease characterized by muscle weakness, which can affect the ability to breathe, hence the gravis) for which there was no known treatment.  She woke up after the lecture, walked up to the great man and asked how to treat myasthenia.  The great man, irritated, said — “It’s just like curare poisoning”, so she went off to the library, looked up curare poisoning, found the treatment for it (physostigmine), administered it to a myasthenic, and became famous.  

40 years ago, L-DOPA was released in the USA for the treatment of Parkinsonism (the subject of a future post). At the brain capillary, an enzyme (L-DOPA decarboxylase) removes the carboxyl group, forming dopamine inside the brain, which binds to (at least 5 different) protein receptors for it, causing a variety of effects in the neurons carrying them (which we’re still trying to figure out in detail). Dopamine is a classic example of an agonist, something which binds to a receptor causing an appropriate physiologic effect.  

So drugs antagonizing dopamine should produce a state resembling Parkinson’s disease. They do. Such drugs should never be used, right?  Wrong !  The first drugs useful against schizophrenia and other psychoses (the phenothiazines, haloperidol) did exactly that. We’re still trying to figure out how they work (and better ways to treat these diseases).

Not all drugs are agonists or antagonists.  The benzodiazepines (xanax, librium, valium, etc. etc.) and the barbiturates bind to a protein receptor for gamma amino butyric acid (the GABA[A] receptor).  Unlike D-Tc which binds to the place acetyl choline wants to bind on its receptor and is thus a competitive antagonist, these drugs bind to a second site on the GABA[A] receptor, causing a conformational change, which makes the receptor more responsive to its natural ligand (gamma amino butyric acid).   This conformational change is called an allosteric effect and the place on the protein where these drugs bind is called an allosteric site.  Allosteric effects can be either positive, as in the example above, or negative.  

The classic negative allosteric drug is strychnine.  It binds to yet another receptor in the brain and spinal cord (this time for glycine, a neurotransmitter like acetylcholine and dopamine).  Glycine is an inhibitory neurotransmitter, meaning it calms down neurons and makes them less likely to fire.  Strychnine poisoning is characterized by painful muscle spasms which can be mistaken for seizures. Strychnine binds to a site on the glycine receptor distinct from that bound by glycine and causes a change in receptor conformation making glycine ineffective as an inhibitor, so this is a negative allosteric effect.  Since the binding site is different, strychnine is a noncompetitive antagonist of glycine.

I saw a case of strychnine poisoning as an intern.  It wasn’t from a suicidal ingestion, but in an addict.  Most nitrogen containing drugs from plants (called alkaloids because they are alkaline) have a bitter taste.  Morphine is one such alkaloid, and narcotic addicts sometimes taste what they are sold, because dealers ‘cut’ the amount of drug in what they say they are selling to make more money. Dealers sometimes would add strychnine (another alkaloid) to what they were selling to give it the bitter taste (and fake out the addict). Dealers have several ways of getting rid of troublesome customers.  One is to give them pure morphine (or whatever they’ve been taking) which gives the addict a much higher dose than they were used to, causing respiratory depression and death.  Another (the present case) is to give them strychnine. The muscle spasms in this patient were spectacular, but not seizures, because the patient was conscious throughout.  They were coming from spinal cord glycine receptors gone wild.

The body uses allosteric effects all the time.  One final example.  2, 3 diphosphoglyceric acid is produced by glycolysis (a way to break down glucose without using oxygen).  The amount of energy released from glucose using oxygen is much (more than 10 times) higher. So 2, 3 diphosphoglyceric acid is a signal that the tissue producing it isn’t getting enough oxygen.  It binds to hemoglobin causing an allosteric change in structure so that the hemoglobin more readily gives up its remaining oxygen.  

Slick isn’t it? Isn’t medicine fascinating? You don’t have a prayer of really understanding this stuff without a solid background in organic chemistry (which is reason #532 why I think premeds should take and pass organic).  

Unfortunately, we’re lightyears from understanding medicine as well as we understand chemistry.  This is where you come in. 

Son of “A responsibility you didn’t know you had”

This is not a new post, but those of you who will be teaching organic chemistry this academic year should read and think about it, as the course will be under way shortly.

The following occured 48 years ago but its implications grew progressively more disturbing the more I saw as I practiced medicine (neurology).  Just before leaving grad school and entering med school I made some money as a TA in a 6 or 8 week summer course in organic chemistry cramming a year’s worth into that tiny space (and into fairly tiny brains given what was taking the course). Some of them had previously flunked organic, others needed to pass it to get into medical school.  Probably this sort of course is still being given and some of you may be making some money the way I did this summer. If so, listen up, you have an important function to perform. 
One loathsome twerp had actually been accepted and was to matriculate in the fall (like me) but only if he passed the course. You know the type, every point taken off was fought over, etc. etc. I was also pretty sure he was also cheating in the lab. The denouement came with the benzoin condensation. We were shooting for a 70% yield, and sure enough starting with 5 grams of benzaldehyde he got 7.5 grams of benzoin.
I wanted him thrown out of the course. He was not. God only knows what damage he caused as an M. D. (assuming he made it through med school).
As an older and wiser Doc once said to me — medicine is a license to steal — the only protection the public has is a doctor who is a little too busy, so that all he does is what he should do, not what he can do.
A few examples of what I’ve seen  #1  A drug addicted urologist who passed his urine tests (for a while) after he was caught, by catheterizing his patients, obtaining their urine, then catheterizing himself and instilling their (presumably) drugfree urine into his bladder.  #2 — The Plaintiff’s friend — a neurologist who didn’t have an examining table in his office and who examined people in their attorney’s office.  #3 The crooked neurologist, who, to make money, diagnosed hapless neurotics as having multiple sclerosis, plunked them in the hospital and gave them unnecessary treatment with high dose corticosteroids.  One of them developed bilateral aseptic necrosis of the hips as a result.  Multiple (billable) expensive tests (EEGs, Evoked responses, EMGs, NCVs) were performed on them — it’s called acute remunerative neurology.
  
Fortunately he has now lost his license to practice medicine — for incompetence. Most of us thought it was fraud rather than incompetence, but he was very smart (crooked docs usually are), and we could never catch him out. 
Where do you come in?  If you find such an individual throw them out of the course.  Would you want them taking care of your mother in a few years?  And if someone says “If I don’t pass organic, I won’t get into medical school”  – think to yourself — “If you can’t pass organic, you don’t BELONG in medical school” and act accordingly (e.g. flunk them).  It may not be easy, and I have no idea what the academic/legal environment is these days, but you’ll be doing society a favor. 

A responsibility you didn’t know you had

 

The following occured 48 years ago but its implications grew progressively more disturbing the more I saw as I practiced medicine (neurology).  Just before leaving grad school and entering med school I made some money as a TA in a 6 or 8 week summer course in organic chemistry cramming a year’s worth into that tiny space (and into fairly tiny brains given what was taking the course). Some of them had previously flunked organic, others needed to pass it to get into medical school.  Probably this sort of course is still being given and some of you may be making some money the way I did this summer. If so, listen up, you have an important function to perform. 

One loathsome twerp had actually been accepted and was to matriculate in the fall (like me) but only if he passed the course. You know the type, every point taken off was fought over, etc. etc. I was also pretty sure he was also cheating in the lab. The denouement came with the benzoin condensation. We were shooting for a 70% yield, and sure enough starting with 5 grams of benzaldehyde he got 7.5 grams of benzoin.

I wanted him thrown out of the course. He was not. God only knows what damage he caused as an M. D. (assuming he made it through med school).

As an older and wiser Doc once said to me — medicine is a license to steal — the only protection the public has is a doctor who is a little too busy, so that all he does is what he should do, not what he can do.

A few examples of what I’ve seen  #1  A drug addicted urologist who passed his urine tests (for a while) after he was caught, by catheterizing his patients, obtaining their urine, then catheterizing himself and instilling their (presumably) drugfree urine into his bladder.  #2 — The Plaintiff’s friend — a neurologist who didn’t have an examining table in his office and who examined people in their attorney’s office.  #3 The crooked neurologist, who, to make money, diagnosed hapless neurotics as having multiple sclerosis, plunked them in the hospital and gave them unnecessary treatment with high dose corticosteroids.  One of them developed bilateral aseptic necrosis of the hips as a result.  Multiple (billable) expensive tests (EEGs, Evoked responses, EMGs, NCVs) were performed on them — it’s called acute remunerative neurology.
  
Fortunately he has now lost his license to practice medicine — for incompetence. Most of us thought it was fraud rather than incompetence, but he was very smart (crooked docs usually are), and we could never catch him out. 

Where do you come in?  If you find such an individual throw them out of the course.  Would you want them taking care of your mother in a few years?  And if someone says “If I don’t pass organic, I won’t get into medical school”  — think to yourself — “If you can’t pass organic, you don’t BELONG in medical school” and act accordingly (e.g. flunk them).  It may not be easy, and I have no idea what the academic/legal environment is these days, but you’ll be doing society a favor. 

Why Organic Chemistry should always be taken (and passed) by pre-meds — part II

Chapter 25 of Clayden is all about synthesis, and as an old Woodward grad student, I loved it.  Ingenuity and elegance on display many times.  Everything in the previous 24 chapters was brought to bear on each problem at hand.  

Just like medicine.

You start in medical school with anatomy and biochemistry, then move on to pathology and pharmacology, then to endocrinology which uses much of the above, then physical diagnosis.  All this in the 2 years before you really get involved with patients.  The handbook for entering med students at Duke is reported to have started with:   “Like to read?  Good, you’ve come to the right place.”

Having spent 2 years reading about the diseases flesh is heir to, at the start of the third year, you are then plunked down in front of a patient to take a history, do a physical exam, come to some sort of understanding about what’s wrong and propose a course of action.  All this to a cynical intern over which stands a even more cynical resident, and above that an attending physician.  

The first few patients take several hours each.  They don’t come with labels saying I’ve got a liver problem, any more than a target molecule says why don’t you try the aldol condensation. Almost invariably, the patients have multiple problems, and you have to be careful that your therapy for one doesn’t adversely affect another — does this remind you of protecting groups?  It should.  

The fact that you have to bring everything you know and have ever studied to bear on an unfamiliar situation is typical of synthesis and medicine.  Even if you’re a specialist, the problems you see don’t necessarily have origins in what you specialize in.  Organic chemistry teaches you to think this way, and if you can’t, you don’t belong in medicine.  For an earlier rumination on this topic see the link at the end.

One example, for any docs reading this.  As a neurologist you get called on to see people who pass out.  One young woman I saw had passed out several times on a hot summer day.  She was thin, but otherwise appeared healthy.   On physical examination (she’d been hospitalized), she had a gorgeous tan.  Moreover, it was all over her body, including the breasts and pelvis.   This was Montana in the 70’s (which was like the US in the 50’s) and there was very little nude sunbathing going on.  That gave the diagnosis away. See the next paragraph for the denouement. I’ve put in some white space so you can think about it before scrolling down.

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She had Addison’s disease and was in adrenal crisis.  Even though it was late evening, I called in an endocrinologist (stat) who drew tons of blood and started treatment immediately.  He told me I’d saved her life.  He said she was on her way out and would have been gone by morning.   She was fainting because she couldn’t maintain her blood pressure when erect.  No intellectual achievement ever gave me satisfaction like this (not even the Woodward seminars). 

For the non MDs:  The total body tan gave things away for the following reason.  To a first approximation, the pituitary gland controls most of the other endocrine glands (adrenal, thyroid, ovaries, testis, but not the pancreas).  It samples the blood to make sure the glands are secreting what they should.  When they aren’t, it pumps out the appropriate hormone (ACTH, TSH, FSH, LH) which tells them to secrete more.  ACTH stands for AdrenoCorticoTrophic Hormone which drives the adrenal cortex to secrete.  However, ACTH is but a part of a larger protein (pro-opiomelanocortin) which contains at least 10 biologically active peptides in its 265 amino acids (ACTH accounts for only 39).  One group is the endorphins, but the clue to the diagnosis is that another peptide contained by both pro-opiomelanocortin and ACTH  is alpha melanocyte stimulating hormone, which makes the pigment cells in your skin (the melanocytes) produce more pigment, darkening the skin (and giving the young woman her great tan).  It doesn’t seem terribly efficient to pump out 10 biologically active peptides when you really want just one, but that’s the way we’re built. 

The link to the earlier rumination

 https://luysii.wordpress.com/2009/09/01/why-organic-chemistry-should-always-be-taken-and-passed-by-pre-meds/

Why premeds should be required to take (and pass) organic chemistry

This post is to be mentioned in the 2 Nov C&EN. I’m reposting it so people can find it. The original came out 1 Sep.

Back when I was posting on “The Skeptical Chymist”, the editor (Stuart Cantrill), told me that noises were being made about dropping organic chemistry from the pre-med curriculum and asked me to comment. I didn’t because the idea seemed so ridiculous. There is no possibility of really understanding anything about cellular biology, drug action, molecular biology etc. etc. without a firm grounding in organic chemistry. You simply must have some idea what vitamins, proteins, DNA and RNA and the drugs you’ll be using look like and how they chemically interact — which is what organic chemistry gives you the background for. Not that you can stop there — but all medical schools teach biochemistry — which starts at organic chemistry and takes off from there. Organic certainly helped me follow molecular biology as it exploded starting in the 60s.

Cynics might say that docs don’t synthesize things or crystallize the drugs they use. Knowing what’s going on under the hood is just esthetic filigree. Just tell them what ‘best practice’ is, and let them follow it like robots. Who cares if they know the underlying science. People drive cars without really understanding what a carburator or a manifold does (myself included).

It wasn’t until I got about 400 pages into the magnificent textbook of Organic Chemistry by Clayden, Greeves, Warren and Wothers (only 1100 action packed pages to go !) that the real answer became apparent. The stuff is impossible to memorize. Only assimilating principles and applying them to novel situations will get you through — exactly like the practice of medicine.

Let us suppose you have an eidetic memory, and know the best treatment for every condition. You wouldn’t have to know any science at all, would you?

What’s wrong with this picture? First of all, there isn’t a best treatment known for every condition. Second, every doc will see conditions and problems that simply aren’t in the books. When I first started out, I was amazed at how much of this there was. I asked an excellent internist who’d been in practice for 30 years if he’d seen it all. He thought he saw something completely new each week. Third, conditions occur in combinations, and many patients (and nearly all the elderly) have many more than one problem. The conditions and treatments interact in a highly nonlinear fashion. The treatment for one problem might make another much worse (see below).

Here is a concrete example using a familiar person (Sonia Sotomayor) and a disorder which should be known to all (the new Swine Flu which swept America and the world this spring). Let’s say that you’re that lucky soul with the perfect memory who knows all the best treatments (well those that exist anyway) and as such you’ve been given the responsibility of taking care of her.

It is public knowledge (e.g. Wikipedia) that Justice Sotomayor has had diabetes since age 8, requiring insulin since that time. Pictures show, that like many diabetics, she is overweight — depending on how tall she is I’d guess by 25 – 45 pounds. Influenza is usually a disease of the fall and winter, and the new Swine Flu is now down in South America, but it’s likely to sweep back up here this fall. We know it’s extremely infectious, but so far fortunately rather benign. There is no guarantee that it will stay that way. Suppose that while down in S. A. it mutated and has become more virulent (a possibility that the CDC takes extremely seriously).

What if she gets the new Swine flu next month? At this point there is no ‘best treatment’ known. Diabetics don’t do well with infections — they get more of them, and have more complications when they do. Her diabetes is certainly going to get worse. What if some think the ‘best treatment’ is corticosteroids (which is often used for severe lung infections) — which will really raise hell with her diabetes? Should you give it? Recall that corticosteroid use during the Asian SARS epidemic (another serious lung infection) seemed to hurt rather than help (Journal of Infection, Volume 51, Issue 2, Pages 98-102). There is no data to help you here and you and your patient don’t have the luxury of waiting for it. Don’t forget that her father died at 42 of heart disease. That could be relevant to what you do. Suppose, like many overweight diabetics she has high blood pressure and elevated lipids as well. How will that affect her management?

Your perfect eidetic memory of medicine will not be enough to help you with her management — you are going to have to think, and think hard and apply every principle of medicine you know to a new and unfamiliar situation with very little data to help you.

Sounds like Organic Chemistry doesn’t it? Anyone without the particular type of mind that is able absorb and apply multiple and (often) conflicting principles doesn’t belong in medicine. A hardnosed mathematician I audited a course from a few years ago, said that people would come up to him saying that if they couldn’t pass Calculus, they wouldn’t get into medical school. He felt that if they couldn’t, he didn’t want them in medical school (I’m not sure he told them this — probably he did). The same thing holds in spades for Organic Chemistry.

Why Organic Chemistry should always be taken (and passed) by pre-meds

Back when I was posting on “The Skeptical Chymist”, the editor (Stuart Cantrill), told me that noises were being made about dropping organic chemistry from the pre-med curriculum and asked me to comment. I didn’t because the idea seemed so ridiculous. There is no possibility of really understanding anything about cellular biology, drug action, molecular biology etc. etc. without a firm grounding in organic chemistry. You simply must have some idea what vitamins, proteins, DNA and RNA and the drugs you’ll be using look like and how they chemically interact — which is what organic chemistry gives you the background for. Not that you can stop there — but all medical schools teach biochemistry — which starts at organic chemistry and takes off from there. Organic certainly helped me follow molecular biology as it exploded starting in the 60s.

Cynics might say that docs don’t synthesize things or crystallize the drugs they use. Knowing what’s going on under the hood is just esthetic filigree. Just tell them what ‘best practice’ is, and let them follow it like robots. Who cares if they know the underlying science. People drive cars without really understanding what a carburator or a manifold does (myself included).

It wasn’t until I got about 400 pages into the magnificent textbook of Organic Chemistry by Clayden, Greeves, Warren and Wothers (only 1100 action packed pages to go !) that the real answer became apparent. The stuff is impossible to memorize. Only assimilating principles and applying them to novel situations will get you through — exactly like the practice of medicine.

Let us suppose you have an eidetic memory, and know the best treatment for every condition. You wouldn’t have to know any science at all, would you?

What’s wrong with this picture? First of all, there isn’t a best treatment known for every condition. Second, every doc will see conditions and problems that simply aren’t in the books. When I first started out, I was amazed at how much of this there was. I asked an excellent internist who’d been in practice for 30 years if he’d seen it all. He thought he saw something completely new each week. Third, conditions occur in combinations, and many patients (and nearly all the elderly) have many more than one problem. The conditions and treatments interact in a highly nonlinear fashion. The treatment for one problem might make another much worse (see below).

Here is a concrete example using a familiar person (Sonia Sotomayor) and a disorder which should be known to all (the new Swine Flu which swept America and the world this spring). Let’s say that you’re that lucky soul with the perfect memory who knows all the best treatments (well those that exist anyway) and as such you’ve been given the responsibility of taking care of her.

It is public knowledge (e.g. Wikipedia) that Justice Sotomayor has had diabetes since age 8, requiring insulin since that time. Pictures show, that like many diabetics, she is overweight — depending on how tall she is I’d guess by 25 – 45 pounds. Influenza is usually a disease of the fall and winter, and the new Swine Flu is now down in South America, but it’s likely to sweep back up here this fall. We know it’s extremely infectious, but so far fortunately rather benign. There is no guarantee that it will stay that way. Suppose that while down in S. A. it mutated and has become more virulent (a possibility that the CDC takes extremely seriously).

What if she gets the new Swine flu next month? At this point there is no ‘best treatment’ known. Diabetics don’t do well with infections — they get more of them, and have more complications when they do. Her diabetes is certainly going to get worse. What if some think the ‘best treatment’ is corticosteroids (which is often used for severe lung infections) — which will really raise hell with her diabetes? Should you give it? Recall that corticosteroid use during the Asian SARS epidemic (another serious lung infection) seemed to hurt rather than help (Journal of Infection, Volume 51, Issue 2, Pages 98-102). There is no data to help you here and you and your patient don’t have the luxury of waiting for it. Don’t forget that her father died at 42 of heart disease. That could be relevant to what you do. Suppose, like many overweight diabetics she has high blood pressure and elevated lipids as well. How will that affect her management?

Your perfect eidetic memory of medicine will not be enough to help you with her management — you are going to have to think, and think hard and apply every principle of medicine you know to a new and unfamiliar situation with very little data to help you.

Sounds like Organic Chemistry doesn’t it? Anyone without the particular type of mind that is able absorb and apply multiple and (often) conflicting principles doesn’t belong in medicine. A hardnosed mathematician I audited a course from a few years ago, said that people would come up to him saying that if they couldn’t pass Calculus, they wouldn’t get into medical school. He felt that if they couldn’t, he didn’t want them in medical school (I’m not sure he told them this — probably he did). The same thing holds in spades for Organic Chemistry.