Well, this blog is slightly overdue, since the ACS meeting has been over for nearly a week. But, I think I’m still adjusting back to East Coast time, so clearly I couldn’t be expected to muse on all the interesting talks I saw until now?! Also I’ve been at a loss without my phone, although I have to say, a phone is easier to recover than your heart (but thanks, Tony, for the title suggestion), especially when you just leave it at a friend’s house…

Anyway, as a final wrap-up from me on the meeting: I went to the “Biocatalysis in polymer science; New materials” session for the afternoon on Thursday, and I have to say that I was impressed both by the quality of talks and the number of people listening to them, as Thursday at an ACS meeting does have the reputation of being a bit of a ghost town.

Three talks that particularly interested me:

Atanu Biswas (of the USDA), who is studying soybean oil as a source of polymer starting materials and biodegradable synthons. These oils, which contain multiple double bonds, have proven difficult to substitute in the past, as all kinds of polymers and crosslinked species are generated. He and his colleagues previously tackled the problem of creating monomeric, functionalized oils by first creating the epoxidized molecule, and then reacting it with amines. In this talk, he reported the use of DEAD to generate hydrazine-substituted molecules. They then utilized these compounds in further reactions to generate Diels-Alder products and some polymers.

Sabine Wallner (a postdoc in Richard Gross’ lab) is studying the metathesis of sophorolipids, natural surfactants consisting of two sugars and a lipid chain that sometimes cyclize spontaneously to form a 26-atom ring. Successful polymerization of these compounds, which are excreted by cells, would result in a biodegradable polymer with many potential uses. What was especially interesting about this talk is that ROMP is normally facilitated by ring strain in the monomeric material. Yet the cyclic sophorolipid is unlikely to be strained because of the very large ring size. In any case, they’ve gotten polymers of up to 100 kD, indicating that there is a lot to learn about this system.

Finally, HN Cheng (from Hercules Incorporated, also one of the chairs of the session) gave a great talk on the application of lipases to create polyamides. Their rationale for the project was to create nylon with an additional amine in the backbone so that it would be water soluble. This isn’t possible with regular polymerization conditions, as the secondary amine would react to form a branch point. He told us that his team had been busy trying to make proteases do this reaction, since it’s just the reverse of their normal function, but with no success. When they tried lipases, though, they got nice polymers both because the formation of amide bonds is not so different from ester bonds, and because the cleavage of these bonds is not possible for the lipase. By careful choice of starting materials, they were able to create multiple polymers that just wouldn’t be accessible with standard synthetic techniques.

In addition to the good talks of the session, I was impressed with the discussions that ensued – clearly everyone was paying attention and there were some helpful suggestions for the authors. Congrats to the POLY section for an exciting meeting.

Catherine Goodman (Assistant Editor at Nature Chemical Biology)

Well, yet another ACS has come and gone. I leave you with a rainbow of chemistry talks.

“The formation of chromium rich particles by the dissolution of ”https://oasys2.confex.com/acs/232nm/techprogram/P981913.HTM">red clays in groundwater monitoring wells." Mysterious chromium in Oklahoma wells found out.

“Identification and characterization of off-flavor aroma impact compounds in canned ”https://oasys2.confex.com/acs/232nm/techprogram/P995694.HTM “>orange juice”

Canned orange juice’s flavor attributes are “tropical fruit, grapefruit, cooked/caramel and medicine.” Yum.

“Research on environmental fate of phenanthrene in Lanzhou Reach of ”https://oasys2.confex.com/acs/232nm/techprogram/P984478.HTM">Yellow River." Math says the pollutants will be stable in the river sediment in 70,000 hours.

“The Pennsylvania ”https://oasys2.confex.com/acs/232nm/techprogram/P960209.HTM">Green fluorophore: A hybrid of Oregon Green and Tokyo Green for the construction of hydrophobic and pH-insensitive molecular probes." The search for the next fluorescent marker. Amazingly, there doesn’t seem to be a band called “Tokyo Green.”

“Highly efficient fluorene-based UV-blue light-emitting polymers with controlled effective conjugation length." Ah, making things that glow.

“”https://oasys2.confex.com/acs/232nm/techprogram/P1012093.HTM">Purple: The dye of dyes" A history lesson with recent archeological findings thrown in. I wish I had seen it.

Polymers and biology, together in perfect harmony. This meeting has intrigued me with a number of sessions about bio-related polymers. Timothy Long’s group had two: one about determining which physical properties of polymers make the best vectors for gene therapy, and one about using DNA base pairs to make a polymer with two sets of properties. Heat it to disassociate the base pairs, and you get a flowy substance, cool to clamp them together again, and you’ve got something strong enough to do something with. Plus, there’s bio-inspired dental polymers from Temple University, enzymes in polymers for sensors from Hawaii Natural Energy Institute, and polymers derived from soybean oil, feathers, and rice. Finally, there was a presentation on making better cigarette filters from Salmon sperm, from the Ogata Research Laboratory, Ltd.

The general crush on bio-related polymers seems to stem from their ability to acquire reactive, “smart” properties from their biological components, as well as from the environmental advantages of making stuff from things that aren’t petroleum. Now, can they produce the self-drying jacket from Back to the Future II?

After the morning session, I jumped in a cab and went to UCSF’s Mission Bay campus – it’s a 43-acre campus that was acquired at no cost to the university and contains a number of laboratories, centers, and research institutes. It’s quite large and is getting bigger: “”https://pub.ucsf.edu/missionbay/faq/“>[a]bout 1,700 faculty, students, scholars and staff already work in the new UCSF Mission Bay campus community. At full build-out, 9,100 people are expected to work and study at the new campus.”

I had a meeting with a professor in Genentech Hall, a 434,000 square foot building where many of the chemical biologists work (there are also a number of structural, molecular, and developmental biologists in the building).

It truly is a beautiful building, and the entire campus looks like it’d be a great place to work – none of the grey/dirty walls and strange odors found in older chemistry/biochemistry bulidings… I’d highly recommend checking out the campus next time you’re in San Francisco – but security is pretty tight, so you might want to sign up for the tour. In the meantime, click here for the virtual tour…

Joshua

Joshua Finkelstein (Associate Editor, Nature)

J.J. La Clair, the controversial chemist (for background, see https://www.nature.com/news/2006/060731/full/442492c.html) in the mutton chop sideburns, gave a talk today to a packed room. It was hot, stuffy, and young in there, as he talked us, mic-less, through what he called “an approach used in a number of labs that I’ve developed, optimized and made easier to use.” As far as I could tell as a layman, the approach had to do with designing synthesis of natural products with florescent labeling and biological tests in mind. I’ll leave an evaluation of the technical content to others more synthesis (or biology)-savvy than I. I’ll just mention that his first slide talked about his Xenobe Research Institute (which is pronounced “zen-OH-bee”). His slide said that the company was working on 80 studies with academe, industry and government. He must be a pretty busy man.

He acknowledged the contretemps over his claimed synthesis of hexacyclinol—and even included on his acknowledgement page a shot of the T-shirt being sold which memorializes the controversy, saying that he salutes creativity in all forms. And yes, that was my headline on the shirt, but I didn’t write it. Reporters very rarely write our own headlines—but we do get to write our own blog post titles. So I decree that the title of this post shall be: “butternut squash soup”, since that is what I am eating right now.

-Our gung-ho enthusiasm for antidepressants mean that there is a certain amount of Prozac in the water these days. Freshwater mussels are less than pleased, though, since Prozac is making them release their larvae before they are viable. Freshwater mussels are sensitive creatures, and 70 percent of the species native to North America are extinct.

-In an irresistible item, a peculiar bird called the Black-Bone Silky Fowl has been found to be packed with carnosine, which has a rep for anti-aging and other positive health effects. The bird is a staple of Chinese medicine, and has soft white feathers over black flesh and bones.

-Check out the brand new Chemical Structure Lookup Service, hosted at NIH,. https://cactus.nci.nih.gov/cgi-bin/lookup/search

-Fucoxanthin, from brown seaweed, is taken up by the fat. It seems to both reduce adipose tissue and turn the fat a bright orange. Anti-obesity clinical trials are in the works.

-Adrienne Kozlowski, retired chemist, and her husband, have taken up hot air ballooning as a hobby. They say it is a perfect diversion for chemists, because manipulating the balloon is all a matter of mastering the laminar flow of the air.

–Peter Murray Rust, of Cambridge, on the future of Chemical information: “We are going to start mashing, and it is going to amaze the world.”

I went to a talk on by UCSB’s Robert Vestberg, on “Synthesis of hydrogels with well defined network structure using Click chemistry”, because I have been hearing this buzzword floating around – “click chemistry”—and I wanted to figure out what it was.

But first, hydrogels. Hydrogels are polymers all cross-linked together and stuffed with water. They can be useful in medicine, for example, as soft contact lenses. They are biocompatible, key molecules can diffuse through them, and they are tough. Often the crosslinks are induced by a blast of radiation—like UV light, for example.

Vestberg and his colleagues are using “click chemistry” to do their linking. The click concept was described quickly as a reaction catalyzed by copper (I) that seems to be a one-size-fits-all room temp process that organizes your molecules into a regular structure. Functional groups can be knitted right in.

At least that was the impression I got. The meeting room in the Marriot was next to some sort of noisy kitchen or workroom, and it was hard to concentrate. It sounded like they were banging the lumps out of large cookie sheets on the other side of the wall. The “backing up” beep of some kind of vehicle was also intermittently heard.

Anyway, the hydrogels are made in little Teflon molds. You can make them with other fluids besides water, too. “We’ve done it in crappy Australian wine that I got from my boss,” says Vestberg, who is pleased with his gels, which can be stretched to 1500% their original length before they break, much more than UV crosslinked hydrogels.

After the talk, I did some reading on click chemistry, which was invented by Barry Sharpless. It seems like a kind of Lego chemistry to me. You may be interested to know that searching the program of abstracts for this meeting with the term “click” yields 42 hits.