EROS Best Reagent Award 2013

Huw Davis, Emory University, USA, has received the the Best Reagent Award for his widely used carbenoid precursor
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Jumping Crystals

Scientists from the United Arab Emirates and Russia examined light-induced jumping crystals by kinematic analysis
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Boron vapour trail leads to heterofullerenes

The simple route to borafullerenes could open up an interesting new avenue of heterofullerene research © Wiley-VCH

http://www.rsc.org/chemistryworld/2012/12/boron-fullerene-heterofullerene-atom-exchange

A team of scientists has developed a simple way to synthesise heterofullerenes – fullerenes with atoms other than carbon in their structure – by exposing fullerenes to boron vapour during their growth. They found that atom exchange with a carbon takes place to form a derivative known as borafullerene. The team believes the process can be easily scaled up and applied to other all-carbon analogues including nanotubes or graphene.

read all at

http://www.rsc.org/chemistryworld/2012/12/boron-fullerene-heterofullerene-atom-exchange

Brevetoxin synthesis

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Anthony crasto brevetoxin synthesis from ANTHONY MELVIN CRASTO Ph.D

The first total synthesis of fuscain

First total synthesis of fuscain

Fuscain is a new furanolactam isolated from the sponge Phacellis fusca from the South China Sea. Furan analogues isolated from marine organisms have valuable medicinal properties. The first total synthesis of fuscain is reported in Journal of Chemical Research December issue. The key step in the synthesis is the formation of seven-membered lactam by acylation of a furan ring using the mild Lewis acid CuSO₄•5H₂O.

Fuscain, a new furanolactam which was originally isolated from the sponge Phacellis fusca collected in South China Sea, showed a moderate cytotoxicity toward P388 and L1210 cell lines. The same sponge yielded three pyrrololactam alkaloids: saldisin, 2-bromoaldisin and debromohymenialdisin.2 Recently, furan analogues isolated from marine organisms have shown anticancer,3–5 antibacterial,6 anticoagulant, antifungal, antimalarial,  antiplatelet, antituberculosis and antiviral activities11. Aldisin-based derivatives can be easily synthesised. However, it is still a challenge to synthesise fuscain. Hence the biological effects of fuscain and its derivatives on cell cycle progression and antitumour activities have rarely been reported. The synthetic route to fuscain is shown below.

The key step is an intramolecular Friedel–Crafts cyclisation to form the seven-membered ring. Various Lewis acids (polyphosphoric acid, POCl3, polyphosphoric acid–acetic acid, POCl3–P2O5, TFA or MSA) have been reported for Friedel– Crafts cyclisation.13,14. Initially, we selected PPA and P2O5 as catalysts but no product was obtained. Because of the structural difference between Alidisin and fuscain, the aromaticity of furan ring is less than a pyrrole ring, and a furan ring usually polymerised under acidic conditions, we selected a relatively mild Lewis acid CuSO4•5H2O to complete the intramolecular cyclisation to form fuscain.

Source: Journal of Chemical Research, Volume 36, Number 12, December 2012 , pp. 736-737(2)

doi: 10.3184/174751912X13528167435099

Yuan-wei Liang, Xiao-jian Liao, Chang-jun Wang, Jin-zhi Guo, Shuo Li and Shi-hai Xu*
Department of Chemistry, Jinan University, Guangzhou 510632, P. R. China

http://stl.publisher.ingentaconnect.com/content/stl/jcr/2012/00000036/00000012/art00016

Click here to find out more about Journal of Chemical Research.

 

Building nanographene by organic synthesis

Direct C-H coupling of pyrene makes nanographenes with defined shape and edge structures

Japanese scientists are making tiny fragments of graphene using direct
cross-coupling of C-H bonds to determine what effect size and edge geometry
have on the properties of carbon materials. By bolting together aromatic hydrocarbons, they can
build nanographene fragments with defined shapes in an attempt to relate geometry to performance.

Speaking at the RSC’s seventh International Symposium on Advancing the Chemical Sciences in Edinburgh, UK, Kenichiro Itami from Nagoya University explained .............read all at

http://www.rsc.org/chemistryworld/2012/06/building-nanographene-organic-synthesis

A new labdane diterpene from Rauvolfia tetraphylla Linn. (Apocynaceae)

A new labdane diterpene from Rauvolfia tetraphylla Linn. (Apocynaceae)

Rauvolfia tetraphylla Linn. (syn. R. canescens L., family: Apocynaceae) holds an important position in the Indian traditional system of medicine, and has other immense applications. This particular plant is regarded as a rich source of a wide variety of important alkaloid constituents such as reserpine, reserpiline, raujemidine, isoreserpiline, deserpidine, aricine, ajmaline, ajmalicine, yohimbines, serpentine, sarpagine, vellosimine and tetrphylline. However, there is no report on the terpenoid constituent from this plant, and we report the isolation from the air-dried stems and branches of R. tetraphylla and structural elucidation of a new labdane diterpene, 3-hydroxy-labda-8(17),13(14)-dien-12(15)-olide (1; Fig. 1) bearing  an unusual -lactone moiety.

Fig. 1 Structure of labdane diterpene

Goutam Brahmachari*, Lalan Ch. Mandal, Dilip Gorai, Avijit Mondal, Sajal Sarkar and Sasadhar Majhi

Doi: 10.3184/174751911X13220462651507

read all at

http://www.sciencereviews2000.co.uk/blog/view/journal-of-chemical-research/58/a-new-labdane-diterpene-from-rauvolfia-tetraphylla-linn-apocynaceae/552

Novel uses of nanoparticle catalytic systems

Novel uses of nanoparticle catalytic systems

Easily prepared and recoverable nanoparticles with a diameter of 10–40 nm, with a high surface area and stability may provide a catalytic system or the support for a catalyst.

http://www.sciencereviews2000.co.uk/blog/view/journal-of-chemical-research/58/novel-uses-of-nanoparticle-catalytic-systems/676

Computational chemistry draws for the first time the “interactive cartographic map" of enzymes during chemical reactions

Enzyme map

Researchers in Spain have used computational chemistry to plot for the first time a "cartographic map" of enzyme behavior during the catalytic process. Features include the moment when a given enzyme is at the point of maximum energy on the way from taking reactants to final product, which all happens within a femtosecond. The study conducted by researchers at the Universitat Jaume I and the University of Valencia was published in Nature Chemistry. "We can [now] make a quantitative estimate of the flexibility of the protein, how much it deforms itself, how much energy you need to deform that protein to generate the reaction that you want," explains UJI's Vicent Moliner.
Computational chemistry draws for the first time the "interactive cartographic map" of enzymes during chemical reactions
http://www.uji.es/UK/ocit/noticies/detall&id_a=33312503

Enzymes Make the World Go 'Round

We often talk about reactions and the molecules that change in those reactions. Those changes don't happen on their own. If you leave a blob of protein in a Petri dish, will it just break down to the amino acids? No. What will do it? Enzymes! Enzymes are the biological substances (proteins) that act as catalysts and help complex reactions occur everywhere in life.

Assembly Line Robots

You all know about cars and the assembly lines where they are made. There are giant robots helping people do specific tasks. Some lift the whole cars, some lift doors, and some just put bolts on. Enzymes are like those giant robots. They grab one or two pieces, do something to them, and then release them. Once their job is done, they move to the next piece and do the same thing again. They are little protein robots inside your cells.

Enzymes complete very, very specific jobs and do nothing else. The robot that was designed to move a car door can't put brakes on the car. The specialized robot arms just can't do the job. Enzymes are the same. They can only work with specific molecules and only do specific tasks. For example, you might have a protein in a cell. Even with hundreds of amino acids in the chain, the overall shape changes if one amino acid is different. That tiny shape change could stop the enzyme from doing its job. Some herbicides are used to block enzyme activity. Plants have adapted by changing one or two amino acids in the enzymes. They can continue to work with the correct proteins and there is no bonding to the herbicides. In the same way that there are specialized robots for different types of cars, there are enzymes for neural cells, intestinal cells, and your saliva.

There are four steps in the process of an enzyme at work:
1. An enzyme and a substrate are in the same area. The substrate is the biological molecule that the enzyme will work on.
2. The enzyme grabs on to the substrate at a special area called the active site. Enzymes are very, very specific and don't just grab on to any molecule. The active site is a specially shaped area of the enzyme that fits around the substrate. The active site is like the grasping handle of the robot on the assembly line. It can only pick up one part.
3. A process called catalysis happens. Catalysis is when the substrate is changed. It could be broken down or combined with another molecule to make something new.
4. The enzyme lets go. This is a big deal. When the enzyme lets go, it returns to normal, ready to work on another molecule of substrate. The first molecule is no longer the same. It is now called the product.

Enzymes

At any given moment, all of the work being done inside any cell is being done by enzymes. If you understand enzymes, you understand cells. A bacterium like E. coli has about 1,000 different types of enzymes floating around in the cytoplasm at any given time.
Enzymes have extremely interesting properties that make them little chemical-reaction machines. The purpose of an enzyme in a cell is to allow the cell to carry out chemical reactions very quickly. These reactions allow the cell to build things or take things apart as needed. This is how a cell grows and reproduces. At the most basic level, a cell is really a little bag full of chemical reactions that are made possible by enzymes!
Enzymes are made from amino acids, and they are proteins. When an enzyme is formed, it is made by stringing together between 100 and 1,000 amino acids in a very specific and unique order. The chain of amino acids then folds into a unique shape. That shape allows the enzyme to carry out specific chemical reactions -- an enzyme acts as a very efficient catalyst for a specific chemical reaction. The enzyme speeds that reaction up tremendously.
For example, the sugar maltose is made from two glucose molecules bonded together. The enzyme maltase is shaped in such a way that it can break the bond and free the two glucose pieces. The only thing maltase can do is break maltose molecules, but it can do that very rapidly and efficiently. Other types of enzymes can put atoms and molecules together. Breaking molecules apart and putting molecules together is what enzymes do, and there is a specific enzyme for each chemical reaction needed to make the cell work properly.

Maltose is made of two glucose molecules bonded together (1). The maltase enzyme is a protein that is perfectly shaped to accept a maltose molecule and break the bond (2). The two glucose molecules are released (3). A single maltase enzyme can break in excess of 1,000 maltose bonds per second, and will only accept maltose molecules.

You can see in the diagram above the basic action of an enzyme. A maltose molecule floats near and is captured at a specific site on the maltase enzyme. The active site on the enzyme breaks the bond, and then the two glucose molecules float away.
You may have heard of people who are lactose intolerant, or you may suffer from this problem yourself. The problem arises because the sugar in milk -- lactose -- does not get broken into its glucose components. Therefore, it cannot be digested. The intestinal cells of lactose-intolerant people do not produce lactase, the enzyme needed to break down lactose. This problem shows how the lack of just one enzyme in the human body can lead to problems. A person who is lactose intolerant can swallow a drop of lactase prior to drinking milk and the problem is solved. Many enzyme deficiencies are not nearly so easy to fix.
Inside a bacterium there are about 1,000 types of enzymes (lactase being one of them). All of the enzymes float freely in the cytoplasm waiting for the chemical they recognize to float by. There are hundreds or millions of copies of each different type of enzyme, depending on how important a reaction is to a cell and how often the reaction is needed. These enzymes do everything from breaking glucose down for energy to building cell walls, constructing new enzymes and allowing the cell to reproduce. Enzymes do all of the work inside cells.

Chiral Column? Here’s One I (Vikki Cantrill) Made Earlier

Continuous-flow Diels–Alder reactions with a homemade HPLC column give good selectivity for >150 h
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http://www.chemistryviews.org/details/news/4972561/Chiral_Column_Heres_One_I_Made_Earlier.html


Continuous-Flow Stereoselective Organocatalyzed Diels–Alder Reactions in a Chiral Catalytic "Homemade" HPLC Column
Valerio Chiroli, Maurizio Benaglia, Franco Cozzi, Alessandra Puglisi, Rita Annunziata, Giuseppe Celentano
Org. Letters 2013.
DOI: 10.1021/ol401390z

carboxylic acids

Organic Chemistry Chapter 21 Klein from Sarah Greening

A molecular database for developing organic solar cells

A molecular database for developing organic solar cell

Harvard researchers have released a massive database of more than 2 million molecules that might be useful in the construction of solar cells that rely on organic compounds for construction of organic solar cells for the production of renewable energy. Developed as part of the Materials Genome Initiative launched by the White House’s Office of … more…

http://www.kurzweilai.net/a-molecular-database-for-developing-organic-solar-cells?utm_source=KurzweilAI+Daily+Newsletter&utm_campaign=4fc1bf53a4-UA-946742-1&utm_medium=email&utm_term=0_6de721fb33-4fc1bf53a4-282116853

Lab Reproduction of Marine Compound with Antibiotic Properties

 

Baringolin is a marine product with antibiotic properties. Image: IRB Barcelona
 

Barcelona, Spain (Scicasts) – Bacterial resistance to drugs leads pharmaceutical labs to be in constant search for new antibiotics to treat the same diseases. For the last thirty years, the sea bottom has yielded a wealth of substances with properties of interest to the pharmaceutical industry.
 
Isolated from a marine microorganism off the coast of Alicante by the company BioMar, baringolin shows promising antibiotic activity at a very low concentration. The Combinatorial Lab headed by Fernando Albericio at the Institute for Research in Biomedicine (IRB Barcelona), which collaborates with BioMar, has now synthesized this molecule and revealed its structure. Today's results open up the possibility to better understand how this substance works and to design derivatives to turn into a viable drug in the next 10 years. These findings are published in todays' online edition of the journal Angewandte Chemie.

read all at

http://scicasts.com/bioit/1858-drug-development/6186-lab-reproduction-of-marine-compound-with-antibiotic-properties

From left to right, this image shows researchers Mercedes Alvárez, Xavier Just-Baringo and Fernando Albericio from the IRB Barcelona.
(Photo Credit: IRB Barcelona)

Xavier Just, PhD student at IRB Barcelona, has reproduced the natural structure in the lab

 Reference article:
Total Synthesis and Stereochemical Assignment of Baringolin
Xavier Just-Baringo, Paolo Bruno, Lars K. Ottesen, Librada M. Cañedo, Fernando Albericio and Mercedes Álvarez.
Angewandte Chemie (2013) http://dx.doi.org/10.1002/ange.201302372 (German Edition) http://dx.doi.org/10.1002/anie.201302372 (International Edition)

Natural Products from St. John's Wort

Natural Products from St. John's Wort

Enatiomers (−)-hyperione A and (−)-hyperione B can be synthesised from a common precursor in ten steps
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http://www.chemistryviews.org/details/ezine/1238795/Natural_Products_from_St__Johns_Wort.html

Cheap nickel catalysis offers alternative to expensive enzymatic resolution, Switching chirality in amino acids

Amino acids are converted to their opposite enantiomers by complexation with a nickel(II) salt and a chiral ligand Switching chirality in amino acids
	Cheap nickel catalysis offers alternative to expensive enzymatic resolution http://www.rsc.org/chemistryworld/2013/06/switching-chirality-amino-acids-nickel-catalysis

Improved R&D Efficiency Through Speedier Method Development (1)

Improved R&D Efficiency Through Speedier Method Development (1)

Various approaches are available for improving the efficiency of analytical...

http://www.pharmaceutical-business-review.com/suppliers/shimadzu-analytical-instrumentation/whitepapers/improved-rd-efficiency-through-speedier-method-development-1

Strategic Approaches to Process Optimization and Scale-up

 
http://drug-scaleup-and-manufacturing.webnode.com/news/strategic-approaches-to-process-optimization-and-scale-up/

Bruce Roth Awarded 2013 Perkin Medal

Roth

Credit: Genentech

Bruce Roth Awarded 2013 Perkin Medal

Honors: Chemist was the first to synthesize the cholesterol-lowering drug atorvastatin, also known as Lipitor
The Society of Chemical Industry (SCI) has selected Bruce D. Roth, vice president of discovery chemistry at Genentech, as the winner of the 2013 Perkin Medal. The annual award is recognized as the highest honor given for outstanding work in applied chemistry in the U.S.
http://cen.acs.org/articles/91/web/2013/06/Bruce-Roth-Awarded-2013-Perkin.html

A Molecule Of Many Colors-With rigid wings and a flexible core, a new compound can switch between two shapes and glow one of three colors.

 

Flexible And Fluorescent

A molecule combining rigid anthraceneimide wings and a flexible cyclooctatetraene core switches between a flat and a bent V shape. The R groups are either hydrogens or n-butyl groups.

Credit: J. Am. Chem. Soc.

A Molecule Of Many Colors

Organic Chemistry: With rigid wings and a flexible core, a new compound can switch between two shapes and glow one of three colors.

A new, flexible, multi-ring organic compound fluoresces red, green, or blue depending on its environment (J. Am. Chem. Soc. 2013, DOI: 10.1021/ja404198h). The molecule’s combination of rigid wings and a flexible center could serve as a general design strategy for molecular sensors, the researchers say.

The molecule, developed by a team of researchers, including Shohei Saito, Stephan Irle, and Shigehiro Yamaguchi of Nagoya University in Japan, has two rigid anthraceneimide wings on opposite sides of a floppy cyclooctatetraene core

read all at
http://cen.acs.org/articles/91/web/2013/06/Molecule-Colors.html

DRUG SYNTHESIS PORTALS ON NET-A COLLECTION

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http://newdrugapprovals.wordpress.com/drug-synthesis/
DRUG SYNTHESIS PORTALS ON NET-A COLLECTION