Dr Andrew L. Lawrence…..Excellent chemistry at work

Lawrence group reaction mechanism

 

http://www.chem.ed.ac.uk/staff/academic-staff/dr-andrew-l-lawrence

organic chemistry research group based at the School of Chemistry at the University of Edinburgh in Scotland.

Dr Andrew L. Lawrence

Dr Andrew L. Lawrence
Lecturer in Organic Chemistry
Room 217

University of Edinburgh
Joseph Black Building
David Brewster Road
Edinburgh
EH9 3FJ

0131 650 4831

Research Interests:
Total Synthesis of Natural Products, Biomimetic Chemistry, Domino Reactions

Our group does research in the area of natural product synthesis and the development of synthetic methodology. The aim of our research is to use nature as a source of inspiration and direction to improve and develop synthetic organic chemistry. Evolution has resulted in the highly efficient biosynthetic chemical pathways observed within living organisms. In our research we aim to harness the power of evolution by mimicking these chemical pathways.

This biomimetic approach to organic synthesis leads to a deeper understanding of how nature operates and illuminates the potential of new chemical reactions. Our biomimetic approach towards organic chemistry is primarily focused upon the synthesis of complex and biologically important natural products. When choosing our target natural products we are drawn to compounds that have extraordinary biosynthetic origins, complex molecular architectures and potent or novel biological/medicinal profiles.

Lawrence group reaction mechanism

We proposed that the unique and complex structure of the kingianin family of natural products was formed in nature through a spectacular radical cation formal Diels-Alder dimerization. We have recently completed a total synthesis of kingianins A, D and F in just ten steps following a strategy inspired by this biosynthetic speculation.

Lawrence research image

Certain phenylethanoid dimers and pseudo-dimers are assembled in nature through elegant sequences of nucleophilic addition reactions (Michael, aldol, Mannich reactions, etc.). We recently accomplished a total synthesis of incarvilleatone via a key biomimetic oxa-Michael/Michael/aldol reaction sequence.

Publications:

Total Synthesis and Structural Revision of the Alkaloid Incargranine B. Brown, P. D.; Willis, A. C.; Sherburn, M. S.; Lawrence, A. L.* Angew. Chem. Int. Ed. 201352, 13273-13275.

Total Synthesis of Kingianins A, D and F. Drew, S. L.; Sherburn, M. S.; Lawrence, A. L. Angew. Chem. Int. Ed. 2013, 52, 4221-4224.

Total Synthesis of Incarviditone and Incarvilleatone. Brown, P. D.; Willis, A. C.; Sherburn, M. S.; Lawrence, A. L.* Org. Lett. 2012, 14, 4537-4539.

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Efficient synthesis of supported proline catalysts for asymmetric aldol reactions

Graphical abstract: Efficient synthesis of supported proline catalysts for asymmetric aldol reactions

Proline has been grafted onto silica supports in a single step by reacting trans-4-hydroxy-L-proline with chloropropyl tethers, without the use of protecting groups for the proline amine and carboxylic acid functional groups. The resulting catalysts have been characterised to show that grafting is through reaction with the 4-hydroxy group. The catalysts have been tested in an asymmetric aldol reaction, and shown to be both more active and more enantioselective than equivalent catalysts prepared using a protection/deprotection route for the proline grafting step.

http://pubs.rsc.org/en/Content/ArticleLanding/2014/CY/C4CY00970C?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2Fcy+%28RSC+-+Catalysis+Science+%26+Technology+latest+articles%29#!divAbstract

Efficient synthesis of supported proline catalysts for asymmetric aldol reactions
A. A. Elmekawy,a J. B. Sweeneya and D. R. Brown*a

*Corresponding authors
aDepartment of Chemical Sciences, University of Huddersfield, Huddersfield HD1 3DH, UK
E-mail: d.r.brown@hud.ac.uk;
Fax: +44 (0)1484 472182 ;
Tel: +44 (0)1484 47339
Catal. Sci. Technol., 2014, Advance Article
DOI: 10.1039/C4CY00970C

Azaheterocycles Made Easy

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Azaheterocycles Made Easy
Flexible route makes azaheterocycles easier to access

 

Azaheterocycles are a highly important class of compounds due to their biological activities and pharmaceutical applications. In particular, dihydroazepines, dihydropyrroles, and pyrroles are constituents of a valuable privileged structure in organic chemistry.

Read more

 

http://www.chemistryviews.org/details/ezine/6508611/Azaheterocycles_Made_Easy.html

Going for Gold in Chiral Amine Synthesis

thumbnail image: Going for Gold in Chiral Amine Synthesis

Going for Gold in Chiral Amine Synthesis
A diphosphine binuclear gold(I) chloride complex catalyzes the asymmetric hydroamination of alkenes

Amines are synthesized most effectively by hydroamination of unactivated alkenes, the enantioselective version of which is best achieved by metal catalysis. Binuclear gold(I) complexes can catalyze the hydroamination of alkenes, however, the harsh and stringent reactions conditions required have prevented full development of this metal for synthesis of chiral amines. In addition, the exact catalytic species involved and whether the activating silver salt participates haChiral Amine Synthesis remained a mystery.

Read more

http://www.chemistryviews.org/details/ezine/6518601/Going_for_Gold_in_Chiral_Amine_Synthesis.html

Directing Venom To Fight Cancer ACS Meeting News: Encapsulated venom peptide can skip healthy cells

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Scorpion toxins may one day be useful as anticancer drugs.
Credit: Courtesy of Dipanjan Pan

Venom from scorpions or honeybees sounds like it wouldn’t do a person much good. But by directing a modified component just to tumors, researchers might leverage it into a drug.

Peptides in some venoms bind to cancer cells and block tumor growth and spread. But they have not yet been developed successfully as anticancer agents because they attack healthy cells too.

Bioengineer Dipanjan Pan and coworkers at the University of Illinois, Urbana-Champaign, are now using polymeric nanoparticles to deliver venom toxin directly to cancer cells.

read at

http://cen.acs.org/articles/92/i33/Directing-Venom-Fight-Cancer.html

 

 

 

 

 

Seeds Sprout Select Nanotubes Nanotechnology: Chemists create just one type of single-walled carbon nanotube from polycyclic precursor

09232-notw1-nanotubesbluecxd

A polycyclic aromatic hydrocarbon seed folds up into a cap when heated on a platinum surface. This cap dictates the chirality of the nanotube, approximately 2 nm in diameter, that grows from it.
Credit: Juan Ramon Sanchez-Valencia

Seeds Sprout Select Nanotubes

Nanotechnology: Chemists create just one type of single-walled carbon nanotube from polycyclic precursor
Using a 96-carbon polycyclic aromatic molecule as a seed, chemists have managed to make single-walled carbon nanotubes (SWNTs) of just one type—a long-sought goal in nanotechnology. Being able to make nanotubes of a specific type should help scientists better exploit their promising electronic properties.  read at……………………..

Creating Cucurbiturils Synthetic route to prepare cucurbiturils substituted at the bridge position has been developed

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Creating Cucurbiturils
Synthetic route to prepare cucurbiturils substituted at the bridge position has been developed
Read more

http://www.chemistryviews.org/details/news/6104831/Creating_Cucurbiturils.html