The Alchemist Newsletter: February 13, 2008

A multitude of awards from the National Academy of Sciences for diverse chemical discoveries caught the eye of The Alchemist this week. In the realm of physical chemistry, or chemical physics, the behavior of water glass may have been unraveled by low-temperature studies of watery phase changes. A new approach to engineering goat's to produce medicinal milk has been devised in Pennsylvania, which could be good news for people with diabetes, while an anticancer compound marketed as antiparasitic could also turn out to be an effective antiviral against HIV. In the legendary world of organic synthesis a wartime effort to synthesize quinine may have been vindicated while Canadian chemists have constructed nanoscopic gas cylinders from barium organotrisulfonate that come with temperature-controlled valves for trapping hydrogen and carbon dioxide.

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Chemical winners

The National Academy of Sciences has bestowed awards on five researchers working in chemistry in honor of their extraordinary contributions. MIT's JoAnne Stubbe receives the $15,000 NAS Award in Chemical Sciences for pioneering work on ribonucleotide reductases. Monsanto's Robert Fraley will receive the $25,000 NAS Award for the Industrial Application of Science for work on transgenic crops. Thomas Eisner a chemical ecologist at Cornell University will receive the $25,000 John J. Carty Award for the Advancement of Science. Stanley Hart of Woods Hole Oceanographic Institution will receive the $20,000 Arthur L. Day Prize & Lectureship for his groundbreaking work in chemical geodynamics. Angelika Amon also of MIT who works on chromosome segregation will receive the $25,000 NAS Award in Molecular Biology.

Chemistry Wins Big

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Water glass

Water is an odd material, with its powerful solvation properties, its anomalous thermodynamic behavior, and the existence of its glassy states. Now, Austen Angell of Arizona State University has found an important clue as to what happens when water makes the transition from the crystalline ice phase to its glassy state. In so doing, he and his colleagues have also gained some useful insights into the behavior of liquid water. Writing in the February 1 issue of Science, Angell and his colleagues looked at both supercooled water and "nanoconfined" glassy ice to pinpoint the exact temperature at which the glass transition takes place. They found that water does not behave like other materials in forming a glassy phase. Instead of a characteristic heat-capacity jump, water's hydrogen-bond network makes water behave as if it were crystalline and it undergoes a order-disorder transition only its heat capacity has fallen to almost zero at 220 K.

New clue in the mystery of glassy water

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Milky medicine

Researchers at the University of Pennsylvania have used gene therapy to cut significantly the time it takes to breed goats that can make therapeutic proteins, such as insulin and anticancer compounds, in their milk. Team member Ina Dobrinski explains the potential, "Having an easier way to harness nature's power to produce large quantities of specific proteins in milk could increase the availability of drugs for people who could otherwise not afford these treatments," she says. The researchers engineered goat sperm using a modified adeno-associated virus to insert a gene for a specific protein and then used these modified sperm in a breeding program to produce female offspring that make the protein in their milk.

Medicine From Milk

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Pharmaceutical multitasking

A drug used to treat parasitic infections, once thought to have anticancer activity, could turn out to be a powerful weapon in the fight against HIV/AIDS, according to Baek Kim and colleagues at the University of Rochester Medical Center. HIV can apparently "hide" itself from the immune system, which means virus numbers can grow without detection over a period of time before symptoms of the disease appear. The new research into the antiparasitic drug miltefosine (Impavido) suggests that it can reveal HIV's hiding places, exposing it to the immune system and so preventing the infection building to life-threatening levels. "Miltefosine puts an end to the long lives of HIV-infected macrophages," Kim explains, "The fact that it is already used in humans could accelerate the process of seeking government approval."

Anti-parasite drug may provide new way to attack HIV

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Chemical mythology

The bitter-tasting alkaloids derived from cinchona bark have been known for the various curative properties for centuries. Quinine is perhaps the best known, In 1945, Robert Burns Woodward and William von Eggers Doering of Harvard University described the synthesis of quinine. Their total synthesis purportedly ended with a three-step reaction originally described by Paul Rabe and Karl Kindler in 1918. This final sequence has courted controversy ever since because although Woodward and Doering published the total sequence there was no evidence that they had actually carried it out before publication and the synthesis has since been dismissed as a chemical myth. Now, Aaron Smith and Robert Williams at Colorado State University have successfully reproduced the Rabe-Kindler protocol. Their success at least demonstrates that Woodward and Doering's total synthesis was theoretically possible. Whether or not they actually carried it out, we may never know.

They Were Right After All

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Molecular gas cylinders

Supramolecular compounds and porous materials that can trap gases within have been around for years, but a team of University of Calgary researchers have come up with what they say might be a viable approach to capturing, storing and transporting gases more safely and efficiently than ever before. "This is a proof of concept that represents an entirely new way of storing gas, not just improving on a method that already exists," explains George Shimizu, "We have come up with a material that mechanically traps gas at high densities without having to use high pressures, which require special storage tanks and generate safety concerns." The material is based on barium organotrisulfonate containing open channels that can be closed off quickly by heating to seal any trapped gas within. These materials might be used to store hydrogen safely for powering fuel cells or in carbon dioxide sequestration efforts aimed at curbing climate change.

Rounding up gases, nano-style

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-- David Bradley, Science Journalist