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A Virtual Chemistry Flashcard App

We love chemistry iPhone apps here at C&EN– and we’ve received word that a new one is arriving soon. So we’re giving you a sneak peek at that app, Chemistry by Design, the brainchild of University of Arizona associate professor Jon T. Njardarson. Continue reading →

Front-line Antibiotics To Fight E. Coli

Guest blogger SeeArrOh comments on the limited chemical weapons available to treat E.coli and its Gram-negative brethren.  SeeArrOh is a Ph.D. chemist working in industry.

Yesterday’s post at In the Pipeline asking what kind of translational research should be done garnered some remarks about the importance of developing antibiotics for Gram-negative bacteria. It’s a timely appeal, because this May an especially virulent strain of the Gram-negative microbe E. coli

, named O104:H4, was discovered in Germany. As reported by the Robert Koch Institute, the German equivalent of the CDC, the outbreak has (to date) killed 35 people and sickened more than 3,200. This deadly strain produces Shiga toxins, which target the kidneys, causing hemolytic-uremic syndrome, a disease characterized by red blood cell death, low platelets, anemia, and  kidney failure.

These outbreaks are not uncommon, as bacteria constantly evolve and adapt. So, when a superbug strikes, why don’t we have anything better to fight it with? Continue reading →

The Medical Metals of Yesterday

SeeArrOh stumbles upon a book that’s something of a chemistry time capsule when it comes to metals and disease. SeeArrOh is a Ph.D. chemist working in industry.

“That which does not kill us makes us stronger” – Nietzsche

“The dose makes the poison” – Paracelsus

When we look back at ancient medicine, we view the treatments once espoused as cures to be near-barbaric: bloodletting, bodily humours, exorcism, even red-hot coins on the skin. Luckily, the advent of the 20th Century brought pharmaceutical companies, sanitation, and well-managed hospital facilities, escapes from the painful and potentially fatal cures of long ago. Modern medicine would never lead us down the path to poison, would it?

Purchasing stamp from The Story of Chemistry, USC-Los Angeles

Maybe we didn’t leave everything from that time behind. While browsing our company bookshelves, I happened across a book entitled The Story of Chemistry with a burlap-brown cover and a thick coat of dust. Published in 1929 by a Mr. Floyd L. Darrow, it pre-dates Chemical Reviews, covering most of the 1920s in medical, agricultural, and synthetic chemistry. To calibrate you to the time period, remember that WWII had not yet occurred, so WWI is referred to as “the Great War”, and the language of science writing waxed a bit poetic, such that the author draws comparisons between “fields of endeavor” and “[the] waters of the Niagara.”

I won’t try to cover all 528 pages, but I was drawn in by Chapter VII, called “Chemistry and Disease.” The author details all of the stunning advances of the late ‘20s, including the isolation of the 4(!) major Vitamins (A-D, with no extra “B-#s”, or E, or K), thyroxine, and steroids, though few chemists knew enough about the structure of these compounds to try rational drug design. (Three of the Vitamins (B1, C, D) would be synthesized in the 1930s. Poor Vitamin A had to wait until 1947.)

Enter Paul Ehrlich, who won the 1908 Nobel Prize in Medicine for his “magic bullet” theory of disease treatment and the first preparation of “specifics,” or chemicals used to kill a single microorganism from among many. Salvarsan, his pioneering treatment for syphilis, was originally called arsphenamine, and contained a diarsenic core. (This was shown in 2005 to be a cyclic analogue of 5 arsenic atoms.) Back then, organoarsenics were not generally recognized as toxic to humans, and scientists would go on to synthesize several other modified versions until more tolerable therapies, such as the sulfa drugs in the 1930s, could be produced. Continue reading →

The Guy With The Namesake Ligand: Brett Fors

Brett Fors (Drahl/C&EN)

To troll the nightly poster sessions at the National Organic Symposium is to combine stargazing with a high school reunion. Nobel laureates rub elbows with undergraduates presenting their work. Graduate school labmates who haven’t seen each other in years catch up. And a spread of food, wine, and beer fuels attendees through the midnight hour.

It was here that I ran into Brett P. Fors, who just obtained his Ph.D. from Stephen Buchwald’s lab at MIT. Fors has already been accorded a privilege that few chemists can claim– he has a ligand named after him. I’ve had a longstanding interest in how chemists name things, so I couldn’t resist asking Fors about that ligand– better known as BrettPhos. Continue reading →

The Guy With The Questions At NOS: Albert S. Matlack

Matlack (Drahl/C&EN)

If you’re attending this year’s National Organic Symposium at Princeton University, you know him as the elderly gentleman who’s stood up to ask multiple seminar speakers about their catalyst loadings during question and answer periods. But there’s much more to Albert S. Matlack besides his inquisitive nature.

Matlack is an adjunct professor of chemistry at the University of Delaware, but he didn’t start his chemistry career there. Before his time in academe he held a research position at the Hercules Powder Company, where he worked right across the hall from none other than 2010 chemistry Nobel laureate Richard Heck. Though Matlack survived the round of layoffs that affected Heck, he remembers those days well.

“After World War II, it was a boom time for chemists,” he recalls. “People believed you could solve all sorts of problems through chemistry.”

But by the 1970′s and 80′s, with the U.S. economy in the doldrums, layoffs seemed to be the solution to financial troubles to companies including Hercules, he says.

In his later days at Hercules, Matlack’s main project involved polymerization of dicyclopentadiene to give a polymer with the tradename Metton. But eventually, “the company cut off Metton and they didn’t know what to do with me,” he says. He left Hercules in 1994, after securing a teaching gig at Delaware with the help of chemistry professor John L. Burmeister.

“The first course I taught was industrial chemistry,” Matlack says. But an article in C&EN (Matlack is an avid reader and a 63-year ACS member) convinced him to try something else– to combine his passions for chemistry and environmentalism and develop a course in green chemistry. He’s been teaching that course ever since. By the late 1990s he decided to write a textbook, but had a hard time finding a publisher for a green chemistry text. “Publishers didn’t think the field was going anywhere,” he says. Today “Introduction to Green Chemistry” is in its second edition.

Even though Matlack has a few other things keeping him busy besides green chemistry– his presidency of the Society of Natural History of Delaware and his two grandchildren– chemistry education is still very important to him. “Many people get turned off from chemistry in their first year learning about it,” he says. “But there are still many problems for chemists to solve, and chemistry can be fun.”

More Matlack:A Delaware News Journal Article about Matlack’s environmentalism efforts

Lazy Cakes And Melatonin: The Sleepy Snack

Brownie packaging, front and back

SeeArrOh has the straight dope on a controversial snack product. SeeArrOh is a Ph.D. chemist working in industry.

(An homage to Terra Sigillata; it might normally be covered on his beat.)

Astute readers of the New York Times may have noticed a front-page article from a few weeks back, highlighting a new late-night snack: Lazy Cakes.  Taking a cue, perhaps, from the substance-laced brownies popular in the late ‘60s, these brownies pack a decidedly sleepy secret: each contains a “proprietary calming blend” of ingredients, chief among which is melatonin. 

Melatonin is a hormone usually secreted by the pineal gland (a pinecone-shaped gland located just above the cerebellum) in humans and other mammals, in response to dark surroundings.  (Note: Although they sound similar, melatonin should not be confused for melanin, the skin pigment formed by sunlight exposure) In mammals, melatonin induces the circadian rhythms associated with sleep, affects the onset of puberty and may help regulate DNA transcription.1,2 Biologically derived from tryptophan, the amino acid and purported suspect of the Thanksgiving “turkey coma”, melatonin has been shown clinically to have benefits for memory loss, in addition to antioxidant potential.  Melatonin capsules have been sold over-the-counter for insomnia and jet lag since the 1980s. 

Technically speaking, the product is labeled a dietary supplement, and as such skirts regulation by the FDA.  One valid concern are possible interactions that melatonin, like other supplements, could have with prescription drugs, a topic addressed both by Terra Sig and C&E News.  More controversy over the soporific snacks springs from their colored packaging and wide availability.  This intrepid blogger ventured out into the wild to recover a sample for analysis.  The packaging, upfront, has a distinctly comic-book appeal: purple and green swirls, a trippy logo evoking That ‘70s Show, and a cartoon brownie mascot leaned back for a snooze.  The brownie itself is compact, and has quite a bit of heft for your average baked good.  The back of the wrapper evokes language usually associated with cigarette labeling: multiple tiny lines of serious text stating Recommended for Adults Only, and Do Not Drive or Operate Heavy Machinery.     

The “calming blend” also includes valerian root, which is commonly found in teas and herbal supplements.  Containing sugar-decorated polycyclic lactones called iridoids, as well as valerenic acid3 derivatives, the extracts have been shown clinically to reduce anxiety and relieve insomnia.4 Passion flower extract brings a dose of alkaloids into the bedtime mix; well-known sleep inducers opium and morphine are part of this general molecular family.  The other ingredients, however, seem to just be along for the ride: current “superfruits” goji berry and açai, with the old Vitamin C standby of rose hips.

For my part, I don’t believe that a baked good packing a pharmaceutical punch should be sold in colorful wrappers, next to the candy bars.  However, having experienced my share of late-night grad school anxiety, I can’t blame someone for wanting a good solid nap, any way they can.

References
1. Fox, Stuart Ira.  Human Physiology, Sixth Ed. Boston: WCB / McGraw Hill, 1999.  pp. 289, 315. 
2. Merck & Co., Inc.  The Merck Index, 13th Ed. New Jersey, 2001. p. 5841
3. Ramharter, J.; Mulzer, J. Org. Lett. 2009, 11, 1151-1153.
4. NIH Dietary Supplement Fact Sheet: Valerian.  2008.  Downloaded from http://ods.od.nih.gov

Delaware’s Day For Richard Heck

Heck (right) and Theopold during the Q&A. Drahl/C&EN

These days, it’s hard to pull Richard Heck away from his orchids, from his life in a rented bungalow in the Philippines. But when you’re a Nobel Laureate, folks tend to want to meet you, to glean some wisdom from your experiences, and to shower you with still more honors.
 
And so it was that Heck, who shared the 2010 Nobel Prize in Chemistry for his work in organometallic chemistry, came back to the States with his wife Socorro to attend a symposium held in his honor. Over five hundred chemists from 20 states and from countries as far away as Japan packed a conference center at the event, held at the University of Delaware, Heck’s academic home from 1971 to 1989. Luminaries in catalysis, including Heck’s fellow laureate, Purdue University’s Ei-ichi Negishi, gave presentations. Via a letter, Delaware’s governor Jack Markell declared May 26, 2011 Richard Heck Day. The day truly belonged to Heck, a self-described introvert who at times seemed humbled by all the fuss.

From what little I’d interacted with Heck, this came as no surprise. In May of last year I interviewed him for a story on named reactions, where his namesake chemistry, the Heck reaction (or Mizoroki-Heck reaction, depending on who you ask) was prominently featured. He was funny and self-deprecating in our brief interview, and he seemed settled enough in that flat in Quezon City that I figured I’d never meet him in person, even after his Nobel Prize was announced. When Delaware chemist Joseph Fox told me about the Heck symposium, I jumped at the chance to attend. Continue reading →

Remedium Technologies Gets A Grip On Severe Bleeding

Maryland is serious about nurturing startups. Drahl/C&EN

In the last year we’ve covered many up-and-coming drugs for controlling the delicate balance between clotting and bleeding. But what happens when something—an injury or a major surgical procedure—overwhelms that system?

Controlling big bleeds is big business, from the battlefield to the operating room. This Monday, at the American Chemical Society’s Middle Atlantic Regional Meeting (MARM) in College Park, Maryland, I heard from Matthew Dowling, CEO of a startup looking to make its mark in that space. The company is called Remedium Technologies, and it’s developing chemically modified versions of a natural biopolymer to make improved materials for stanching blood flow.

Remedium is one of several companies getting on its feet with help from technology incubation programs the University of Maryland. Representatives from several of those companies, including Dowling, gave talks at a MARM symposium on the science of startups. Look here for the MARM session’s program- it includes other companies in the drug and vaccine space, including Azevan Pharmaceuticals (which C&EN wrote about in 2001 when it was called Serenix), Leukosight, and SD Nanosciences.

The biochemical pathway that regulates clotting can’t support severe injuries that lead to profuse bleeding, Dowling said Monday. While several treatments exist for this kind of severe injury, where sutures might not work to close a wound, they have drawbacks that Dowling thinks Remedium’s technology can address.

The company’s material of choice is chitosan, a biopolymer that can be scavenged from waste shells of shrimp or crabs. Chitosan wound dressings are already on the market, but they become saturated with blood and quit sticking to tissue after about 30 minutes, which can lead to more bleeding. As a bioengineering graduate student at Maryland, Dowling developed an alternative chitosan modified with hydrophobic groups that help it stick to tissues longer. This modified biomolecule is the basis of Remedium’s technology. The company likens the material to Velcro because it is the sum total of weak interactions between hydrophobic groups and tissue that help the material stick around, Dowling explains. Once the wound has had time to heal, the material can be gently peeled away.  The chemical structure of Remedium’s hydrophobic groups is proprietary; Dowling used benzene n-octadecyl tails in graduate school.

The company has two products in development- a modified chitosan “sponge” and a spray-on blood clotting foam. Neither of those products is yet available for purchase. In College Park, Dowling showed a video demonstrating how the modified chitosan makes blood congeal quickly, and how the effect can be reversed by applying alpha-cyclodextrin. In a second video, the sponge is tested on a bleeding pig that’s had a major blood vessel cut open. This presentation is similar to what Dowling gave Monday.

Dowling has been running Remedium full-time since he obtained his doctorate from Maryland in 2010—the company was founded while he was still in graduate school, and several classmates are also in the company’s management. The company has an exclusive license for the chitosan technology from the university, and has four patents pending. It has also won several business competitions, including Oak Ridge National Laboratory’s (ORNL) 2010 Global Venture Challenge. Dowling says the university’s technology incubation resources are what made it possible for him to start a company while still in grad school, from providing office space in a building just off campus, to regular meetings with staffers knowledgeable about navigating the regulatory and funding process.