December 2008 Technical Newsletter
December 2008 Fluorous Technical Newsletter
CEOverture…
Dear Reader,
Welcome to what has become a popular holiday season gift from Fluorous Technologies–our annual Fluorous Year-In-Review Technical Newsletter. In addition to highlighting our own product developments in 2008 we’ve canvassed the fluorous literature and selected key technology developments from a wide range of applications. As you will read below, it has been an exciting year chock full of progress on both technology and business fronts. 2009 should be even better, so stay tuned.
I’d like to take this opportunity to thank all of you once more for your interest and wish everyone the happiest of holiday seasons.
Cheers,
Phil
Small Molecule and Library Synthesis
Fluorous techniques were initially applied to small molecule synthesis, an area that remains active today. The past year has seen the development of new reagents and methodologies, continued application in library synthesis, and use in drug discovery efforts.
New Reagents
New reagents that have been described in 2008 include new fluorous-tagged TEMPO derivatives for oxidations,1 improved fluorous-tagged Mukaiyama salts for amide bond formation,2 along with various ligands for catalytic transformations, including ones for asymmetric cyclopropanations3 and olefin metathesis.4 Each of these can be removed post-reaction using either fluorous solid phase extraction (FSPE) or fluorous liquid-liquid extraction (FLLE).
New Methodologies
New methodologies for library synthesis have been developed in 2008. For example, Prof. David Procter described using fluorous tags and samarium iodide in the synthesis of various heterocycles.5 One of the more interesting papers came from the University of Valencia where Prof. Santos Fustero’s group conducted a direct comparison of solution phase, solid phase, and fluorous phase synthesis of cyclic amino acids.6 They found that fluorous assisted synthesis was preferred, since it provided more consistent results with simpler workflows than either traditional solution phase or solid phase approaches.
Diversity Oriented Synthesis
Two groups employed fluorous tags in diversity-oriented synthesis (DOS) with great success. First, researchers led by Prof. Adam Nelson used a fluorous approach with cascade olefin metathesis to produce a 96 member library containing 84 different core heterocycles, a remarkable level of chemical diversity for a library of that size.7 Being able to use one general purification technique, FSPE, is highly desirable when working with a dense DOS library as it provides a simplified purification of intermediates and products.
The second group of researchers, at the University of Cambridge, recently reported their efforts toward discovery of new antibacterial agents.8 In this case, the most active compounds were identified by following-up on hits found from a DOS library synthesized using fluorous tags–an excellent example of how fluorous methods may be integrated into a drug discovery program.
Peptide,Carbohydrate, and Oligonucleotides
The preparation of biomolecules has been found to benefit from fluorous synthesis and purification techniques. Oligosaccharide synthesis, in particular, has made great advances in 2008.
Carbohydrate Synthesis
New tags and fluorous mixture synthesis(FMS) techniques for solution phase synthesis of carbohydrate libraries were reported by Prof. Mizuno, who also published methods where FLLE was used as the primary separation method.9 In FMS, multiple reactions can be conducted at one time in a single reaction vessel. The resultant mixture of products is easily separated by a fluorous HPLC column. In this work, Prof. Mizuno synthesized and purified six different disaccharides in a single reaction starting from three differentially tagged donors and two differentially tagged acceptors.
Researchers at Iowa State University led by Prof. Nicola Pohl reported a synthetic methodology based on the separation of singly tagged vs. doubly tagged compounds.10 In this instance, the coupling of a monomer unit to a growing fluorous-tagged oligosaccharide does not always proceed to completion, thus making purification a challenge and necessitating the undesirable use of large excesses of monomer. By using a fluorous-tagged monomer instead, the resultant product contains two fluorous tags while all other species contain one fluorous tag. The desired doubly tagged product is easily separated from the singly tagged components using FSPE. This innovative strategy could also be applied to peptides constructed using ligation chemistry.
Oligonucleotide Synthesis
Berry and Associates has taken the lead in the commercialization of fluorous tags for oligonucleotide synthesis. They initially developed materials and methods using fluorous DMT phosphoramidites as temporary tags for the synthesis and purification of oligonucleotides. In 2008, they have expanded their offering of fluorous reagents to include permanent fluorous tags for immobilization, fluorous tags with a fluorescein, and fluorous tags with a dabcyl label. Whether you are looking to utilize fluorous tags in the synthesis of unmodified or modified oligonucleotides, Berry and Associates and fluorous techniques can meet your needs.
Fluorous at the Interface of Chemistry and Biology
In 2008 fluorous techniques continued to advance into areas such proteomics and chemical biology. Bioorthogonality and complementarity with various detection methods, including mass spectrometry and fluorescence detection, make fluorous methods particularly attractive in these applications as described in a recent Science perspective.11 The primary advances this year have been in the area of fluorous immobilization. Fluorous-tagged molecules can be spotted onto a fluorous-modified surface to provide arrays with very low non-specific binding, low and uniform background fluorescence, and simpler workflows. Fluorous arraying results in non-covalently bound probes that are displayed in a specific orientation.
Carbohydrate Microarrays
Professor Nicola Pohl, who pioneered the use of fluorous immobilization of carbohydrates to form microarrays, continued her research and published several important papers. Her group developed methods to attach fluorous tags to existing carbohydrate content and immobilize the newly tagged content onto fluorous slides.12 Carbohydrate-lectin binding affinities were quantified and the values found using the fluorous microarray were in concordance with other standard methods, including SPR. Her group also used fluorous-based microarrays to discover a previously unknown binding interaction of glycero-D-manno-heptose with ConA.13
Fluorous NIMS
Scientists at The Scripps Research Institute combined fluorous immobilization with direct MS detection by nanostructure-initiator mass spectrometry (NIMS) to investigate enzyme activity on carbohydrates.14
Fluorous NIMS provided investigators with the tools to both detect enzyme activity and characterize the reaction product of the immobilized probes. The low non-specific binding of the fluorous surface allowed for incubation of the immobilized probes with cell lysates in addition to purified enzyme.
Peptide Microarrays
It’s not just carbohydrates that can be immobilized, however, as Fluorous Technologies Inc. scientists in collaboration with Prof. Pohl’s group have demonstrated that peptide microarrays can be formed using fluorous tags. The peptide arrays were used to detect protease activity. These results, to be published shortly, expand the scope of fluorous immobilization techniques to another important class of biomolecules.
2008 Events and Awards
ACS Award for Creative Work in Fluorine Chemistry
University of Pittsburgh chemistry professor and Fluorous Technologies Inc. founder, Dr. Dennis P. Curran was the 2008 recipient of the ACS Award for Creative Work in Fluorine Chemistrywhich he received at the 235th ACS National Meeting in New Orleans. The Award is presented annually for outstanding contributions to the advancement of the chemistry of fluorine. A special issue of Journal of Fluorine Chemistry was published to commemorate the award. In addition to papers from leading fluorous researchers, the issue contains a brief review from Dr. Curran on the history of fluorous chemistry within his labs.
Want to Get Started in 2009?
Are you intrigued by the potential of fluorous techniques and want to know more? There are several ways to learn more beyond scouring the available literature or the references listed below. You can visit our href=”http://www.fluorous.com”>website to view and download application notes, references, and presentations which describe various fluorous applications. Or visit F-Blog, our blog which keeps you up to date on the latest developments. Another valuable resource is the Sigma-Aldrich website, where Sigma-Aldrich and Fluorous Technologies Inc. have developed a fluorous portal which lists products by application. In addition, a Learning Center with links to presentations and application notes is available. Finally, for a more personal touch, contact Fluorous Technologies Inc. directly! Email or call us (412-826-3050) and we will be happy to answer any questions that you may have. Whether your research entails synthesis, analysis, or materials, fluorous methods and Fluorous Technologies Inc. can help increase your research productivity.
What’s Planned at Fluorous Technologies in 2009?
With 2008 winding down, it’s time to look forward to what lies in store for 2009. We plan on accomplishing the following:
- Major revision of fluorous.com with a focus on fluorous applications
- Addition of new sales and distribution channels to make purchasing of fluorous materials easier
- Sponsorship of the Third
International Symposium on Fluorous Technologies (ISoFT’09) conference in Jackson Hole, Wyoming - Continued production of small molecule libraries through a NIH Pilot Scale Libraries grant leading to novel chemical scaffolds and synthetic strategies
- Demonstration of a fluorous-based mixed microarray which combines carbohydrate and peptide probes on a single surface
- Development of new reagents and protocols for quantitative proteomics
References
- 1. a) Gheorghe, A.; Chinnusamy, T.; Cuevas-Yanez, E.; Hilgers, P.; Reiser, O., Org.Lett. 2008, 10, (19), 4171. b) Dobbs, A. P.; Penny, M. J.; Jones, P., Tetrahedron Lett. 2008, 49, (49), 6955.
- 2. Matsugi, M.; Suganuma, M.; Yoshida, S.; Hasebe, S.; Kunda, Y.; Hagihara, K.; Oka, S., Tetrahedron Letters 2008, 49, (46), 6573
- 3. Miura, T.; Itoh, K.; Yasaku, Y.; Koyata, N.; Murakami, Y.; Imai, N., Tetrahedron Lett. 2008, 49, (40), 5813
- 4. Hensle, E. M.; Tobis, J.; Tiller, J. C.; Bannwarth, W., J. Fluorine Chem. 2008, 129, (10), 968
- 5. a) James, K. M.; Willetts, N.; Procter, D. J., Org. Lett. 2008, 10, 1203. b) Ovens, C.; Martin, N. G.; Procter, D. J., Org. Lett. 2008, 10, (7), 1441.
- 6. Fustero, S.; Sinchez-Rosello, M.; Rodrigo, V.; Sanz-Cervera, J. F.; Piera, J.; Simon-Fuentes, A.; del Pozo, C., Chem.–Eur. J. 2008, 14, (23), 7019.
- 7. Morton, D.; Leach, S.; Cordier, C.; Warriner, S.; Nelson, A. Angew. Chem. Intl. Ed. 2008, DOI: 10.1002/anie.200804486.
- 8. Wyatt, E.; Galloway, W.R.J.D.; Thomas, G.L.; Welch, M.; Loiseleur, O.; Plowright, A.T.; Spring, D.R. Chem. Commun. 2008, 4962.
- 9. a) Tojino, M.; Mizuno, M., Tetrahedron Letters 2008, 49, (41), 5920-5923. b) Mizuno, M.; Kitazawa, S.; Goto, K., J. Fluorine Chem. 2008, 129, (10), 955.
- 10. Park, G.; Ko, K.-S.; Zakharova, A.; Pohl, N. L., J. Fluorine Chem. 2008, 129, (10), 978.
- 11. Curran, D. P., Science 2008, 321, (5896), 1645.
- 12. Chen, G.-S.; Pohl, N. L., Org. Lett. 2008, 10, (5), 785.
- 13. Jaipuri, F.A.; Collet, B.Y.M.; Pohl, N.L., Angew. Chem. Int. Ed. 2008, 47, (9), 1707
- 14. Northen, T. R.; Lee, J.-C.; Hoang, L.; Raymond, J.; Hwang, D.-R.; Yannone, S. M.; Wong, C.-H.; Siuzdak, G., Proc. Nat. Acad. Sci. 2008, 105, (10), 3678.