Divergent and concise total syntheses of two lycopodium alkaloids, lyconadins A and C have been developed. The synthesis of lyconadin A, having potent neurotrophic activity, features an efficient one-pot ketal removal and formal aza-[4+2] cyclization to form the cagelike core structure. A tandem ketal removal/Mannich reaction was developed to build the tricyclic structure of lyconadin C. Both lyconadins A and C were synthesized from a pivotal intermediate.
Like-a-podium: Divergent total syntheses of the two Lycopodium alkaloids lyconadins A and C were developed from the intermediate 1. The synthesis of lyconadin A features a highly efficient ketal removal/formal aza-[4+2] cyclization to form the core structure. A ketal removal/Mannich reaction was used to construct the core structure of lyconadin C. The concise and flexible synthetic route offers a platform for the development of anti-neurodegenerative agents.
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Architect and freelance illustrator Maja Wrońska (previously) continues to amaze with her beautifully executed watercolor paintings of iconic cityscapes from around the world. From London and Paris to Prague and even Disney Land, the Polish artist brings a colorful, dreamlike perspective to everything she paints. Wrońska has been extremely active since we first covered her work here back in 2012, see much more on Behance, and pickup prints and other things on Society6.
Based on reviews from BeerAdvocate, Beer Viz, a visualization class project, asks you to choose a general style of beer and a beer that you like. Then it shows you beers that are similar, based on appearance, taste, aroma, and overall score. It's like a visual version of the beer recommendation system we saw last year.
We’ve had some trouble with obnoxious pop-ups displaying on the site. Problem has been resolved. More on that here.
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Self Doubt (Macaque) (detail) 2010 Carved plywood plinth, Bell jar 13 x 13 x 58 inches
We've mentioned this before, but one of the coolest candidates for Material of the Future is silk. It's insanely tough, and in the human body, doesn't put the same strain on tissue that metal does. It can also harmlessly degrade in the body over time, which it makes it handy for use in medical devices.
In a study run by Tufts University researchers, a team harvested silk from silkworm cocoons and used it to make plates and screws. They recently tested the materials in six rats and, after four to eight weeks, the silk had dissolved. Next up: the silk screws and plates could be used to mend broken bones in humans, then allow the silk to melt away, rather than requiring another surgery for removal. The researchers want to use the technique to treat face injuries at first, then expand to other broken bones.
They aren't the first to toy with this idea; other researchers have suggested implants like this could come to humans by 2030. So just don't break anything until then, and you're good.
The structural organization of three different families of semicrystalline π-conjugated polymers is reported (poly(3-hexylthiophene) (P3HT), poly[2,6-(4,4-bis-alkyl-4H-cyclopenta-[2,1-b;3,4-b0]-dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)](cyclopentadithiophene-benzothiadiazole) (CDT-BTZ) and poly(N,N"-bis-2-octyldodecylnaphtalene-1,4,5,8-bis-dicarboximide-2,6-diyl-alt-5,5–2,2-bithiophene (P(NDI2OD-T2))). These have triggered significant interest for their remarkable charge-transport properties. By performing molecular mechanics/dynamics simulations with carefully re-parameterized force fields, it is illustrated in particular how the supramolecular organization of these conjugated polymers is driven by an interplay between the length and nature of the conjugated monomer unit and the packing of their alkyl side chains, and to what extent it impacts the charge-carrier mobility, as monitored by quantum-chemical calculations of the intermolecular hopping transfer integrals. This Progress Report is concluded by providing generic guidelines for the design of materials with enhanced degrees of supramolecular organization.
By means of combined computational tools based on molecular mechanics/dynamics and quantum-chemistry, the relationships between the chemical structure and the supramolecular organization of p- and n-type p-conjugated polymers are highlighted and the implications for charge transport are discussed. Specifically, the crucial role of the alkyl side chains in driving a structural organization that favors high hole and/or electron mobility is emphasized.
Eu achava que esse dia nunca ia chegar e chegou… ! veja só vcs, o Galvão simplesmente não viu o gol do Oscar, contra a Africa do Sul, e não gritou GOOOOOLLLLLLLLLLL! Será que o véio tá com catarata, Brasil? Ou é ressaca de carnaval?