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American Chemical Society Division of Organic Chemistry 243Rd ACS National Meeting, San Diego, CA, March 25-29, 2012

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American Chemical Society Division of Organic Chemistry 243Rd ACS National Meeting, San Diego, CA, March 25-29, 2012 American Chemical Society Division of Organic Chemistry 243rd ACS National Meeting, San Diego, CA, March 25-29, 2012 A. Abdel-Magid, Program Chair; R. Gawley, Program Chair SUNDAY MORNING Ralph F. Hirschmann Award in Peptide Chemistry: Symposium in Honor of Jeffery W. Kelly D. Huryn, Organizer; D. Huryn, Presiding Papers 1-4 Biologically-Related Molecules and Processes A. Abdel-Magid, Organizer; T. Altel, Presiding Papers 5-16 New Reactions and Methodology A. Abdel-Magid, Organizer; N. Bhat, Presiding Papers 17-28 Asymmetric Reactions and Syntheses A. Abdel-Magid, Organizer; D. Leahy, Presiding Papers 29-39 Material, Devices, and Switches A. Abdel-Magid, Organizer; S. Thomas, Presiding Papers 40-49 SUNDAY AFTERNOON James Flack Norris Award in Physical Organic Chemistry: Symposium to Honor Hans J. Reich G. Weisman, Organizer; G. Weisman, Presiding Papers 50-53 Understanding Additions to Alkenes D. Nelson, Organizer; D. Nelson, Presiding Papers 54-61 Biologically-Related Molecules and Processes A. Abdel-Magid, Organizer; B. C. Das, Presiding Papers 62-73 New Reactions and Methodology A. Abdel-Magid, Organizer; T. Minehan, Presiding Papers 74-85 Asymmetric Reactions and Syntheses A. Abdel-Magid, Organizer; A. Mattson, Presiding Papers 86-97 Material, Devices, and Switches A. Abdel-Magid, Organizer; Y. Cui, Presiding Papers 98-107 SUNDAY EVENING Material, Devices, and Switches, Molecular Recognition, Self-Assembly, Peptides, Proteins, Amino Acids, Physical Organic Chemistry, Total Synthesis of Complex Molecules R. Gawley, Organizer Papers 108-257 MONDAY MORNING Herbert C. Brown Award for Creative Research in Synthetic Organic Chemistry: Symposium in Honor of Jonathan A. Ellman S. Sieburth, Organizer; S. Sieburth, Presiding Papers 258-261 Playing Ball: Molecular Recognition and Modern Physical Organic Chemistry C. Nuckolls, Organizer; D. Johnson, Organizer; F. Hof, Organizer; A. Sather, Presiding Papers 262-271 Chemistry of Life A. Abdel-Magid, Organizer; M. Smith, Presiding Papers 272-283 New Reactions and Methodology A. Abdel-Magid, Organizer; B. Banik, Presiding Papers 284-295 Asymmetric Reactions and Syntheses A. Abdel-Magid, Organizer; M. Watson, Presiding Papers 296-307 Material, Devices, and Switches A. Abdel-Magid, Organizer; J. F. Tannaci, Presiding Papers 308-317 MONDAY AFTERNOON Elias J. Corey Award for Outstanding Original Contribution in Organic Synthesis by a Young Investigator: Symposium in Honor of Jeffrey S. Johnson M. Kozlowski, Organizer; M. Kozlowski, Presiding Papers 318-321 Recent Progress and Applications of Multicomponent Reactions A. Doemling, Organizer; A. Doemling, Presiding Papers 322-327 Chemistry of Life A. Abdel-Magid, Organizer; M. Distefano, Presiding Papers 328-339 New Reactions and Methodology A. Abdel-Magid, Organizer; N. A. Yakelis, Presiding Papers 340-351 Asymmetric Reactions and Syntheses A. Abdel-Magid, Organizer; C. Larsen, Presiding Papers 352-363 Material, Devices, and Switches A. Abdel-Magid, Organizer; M. C. Stefan, Presiding Papers 364-373 MONDAY EVENING Sci-Mix R. Gawley, Organizer Papers 138, 143-144, 164, 169, 173, 177, 189, 195-197, 229, 230, 236, 246, 514, 522, 529, 537, 542, 550, 557, 560, 562, 573, 578, 588-589, 602, 619, 778, 785, 791-792, 797, 802, 806, 833, 850, 852, 863, 866, 868, 870, 892, 902, 913 TUESDAY MORNING Ernest Guenther Award in the Chemistry of Natural Products: Symposium in Honor of Stephen Hanessian V. Snieckus, Organizer; V. Snieckus, Presiding Papers 375, 374, 376-377 Chemical Neuroscience C. Lindsley, Organizer; C. Hopkins, Organizer; S. Kuduk, Organizer; C. Lindsley, Presiding Papers 378-384 Peptides, Proteins, and Amino Acids A. Abdel-Magid, Organizer; L. Desai, Presiding Papers 385-395 New Reactions and Methodology A. Abdel-Magid, Organizer; B. Wakefield, Presiding Papers 396-407 Physical Organic Chemistry: Calculations, Mechanisms, Photochemistry, and High-Energy Species A. Abdel-Magid, Organizer; S. J. Schmidtke, Presiding Papers 408-418 Metal-Mediated Reactions and Syntheses A. Abdel-Magid, Organizer; M. Organ, Presiding Papers 419-429 Molecular Recognition and Self-Assembly A. Abdel-Magid, Organizer; B. Purse, Presiding Papers 430-440 TUESDAY AFTERNOON ACS Award for Creative Work in Synthetic Organic Chemistry: Symposium in Honor of Gregory C. Fu C. Maryanoff, Organizer; C. Maryanoff, Presiding Papers 441-445 Nanostructured Electronic Materials G. Girolami, Organizer; L. McElwee-White, Organizer; L. McElwee-White, Presiding Papers 446-453 Heterocycles and Aromatics A. Abdel-Magid, Organizer; J. Fotie, Presiding Papers 454-464 New Reactions and Methodology A. Abdel-Magid, Organizer; B. Goess, Presiding Papers 465-476 Physical Organic Chemistry: Calculations, Mechanisms, Photochemistry, and High-Energy Species A. Abdel-Magid, Organizer; H. Banks, Presiding Papers 477-486 Metal-Mediated Reactions and Syntheses A. Abdel-Magid, Organizer; G. Melikyan, Presiding Papers 487-498 Molecular Recognition and Self-Assembly A. Abdel-Magid, Organizer; E. Masson, Presiding Papers 499-510 TUESDAY EVENING Asymmetric Reactions and Syntheses, New Reactions and Methodology R. Gawley, Organizer Papers 511-657 WEDNESDAY MORNING Ronald Breslow Award for Achievement in Biomimetic Chemistry: Symposium in Honor of Alanna Schepartz A. Phillips, Organizer; A. Phillips, Presiding Papers 658-661 Building Blocks for Chemical Biology K. Kumar, Organizer; K. Kumar, Presiding Papers 662-666 Heterocycles and Aromatics A. Abdel-Magid, Organizer; S. C. Rasmussen, Presiding Papers 667-677 Molecular Recognition and Self-Assembly A. Abdel-Magid, Organizer; A. Sykes, Presiding Papers 678-688 Total Synthesis of Complex Molecules A. Abdel-Magid, Organizer; G. Wei, Presiding Papers 689-700 Metal-Mediated Reactions and Syntheses A. Abdel-Magid, Organizer; R. Stockland, Presiding Papers 701-711 WEDNESDAY AFTERNOON New Reactions and Methodology A. Abdel-Magid, Organizer; R. Rios-Torres, Presiding Papers 712-723 Heterocycles and Aromatics A. Abdel-Magid, Organizer; J. Schomaker, Presiding Papers 724-734 Molecular Recognition and Self-Assembly A. Abdel-Magid, Organizer; A. Gorodetsky, Presiding Papers 735-745 Total Synthesis of Complex Molecules A. Abdel-Magid, Organizer; L. Rossano, Presiding Papers 746-757 Metal-Mediated Reactions and Syntheses A. Abdel-Magid, Organizer; D. Watson, Presiding Papers 758-768 WEDNESDAY EVENING Chemistry of Life, Biologically-Related Molecules and Processes, Heterocycles and Aromatics, Metal-Mediated Reactions and Syntheses R. Gawley, Organizer Papers 769-914 ORGN 1 Electronic effects on protein structure Ronald T. Raines, [email protected]. Departments of Biochemistry and Chemistry, University of Wisconsin - Madison, Madison, WI 53706-1544, United States In 1951, Linus Pauling first reported on the hydrogen bonds between backbone amides that are common in α-helices and β-sheets. We have discovered another intimate interaction between backbone amides. This interaction arises from the delocalization of a lone pair of electrons (n) from an oxygen atom to the anti-bonding orbital (π*) of the subsequent carbonyl group. The signature of this n→π* interaction is most evident in the pyramidalization of the acceptor carbonyl group. Our ab initio calculations predict significant n→π* interactions in certain regions of the Ramachandran plot. We have validated these predictions by a statistical analysis of a large, non-redundant subset of protein structures determined to high resolution. We find n→π* interactions to be especially abundant in common secondary structures such as α-, 310-, and polyproline II helices, and twisted β-sheets. n)(π Pauli repulsion attenuates the n→π* interaction with olefins and compromises their utility as peptidomimetics. In addition to their evident effects on peptide and protein conformation, n→π* interactions could play important roles in protein folding and function, and merit inclusion in computational force fields. Finally, we have identified important n→π* interactions in small molecules (such as aspirin) and with the chromophore of GFP and other fluorescent proteins, and noted that an n→π* interaction could have directed the prebiotic genesis of ribonucleotides. ORGN 2 Building selective diatomic gas sensors: Nature’s way Michael A. Marletta, [email protected]. Department of Chemistry, The Scripps Research Institute, La Jolla, CA 92037, United States Nitric oxide (NO) is a signaling agent in the cardiovascular system and other tissues. The immune system also utilizes NO in the host response to infection. Signaling concentrations of NO are low (pM), thereby avoiding toxicity. Immune system-derived NO is formed at µM concentrations and these local high levels function in cell killing. NO is formed via nitric oxide synthase (NOS) through the conversion of arginine to citrulline and NO. A primary NO receptor is the soluble isoform of guanylate cyclase (sGC) that uses a heme cofactor to trap NO. The heme domain of sGC was found to be part of the H-NOX (H eme-N itric oxide OX ygen) family of proteins with homologues in aerobic and anaerobic prokaryotes. Structural and biochemical studies have provided molecular explanations for the observed selectivity in ligand binding in various H-NOXs. Study of H-NOX sensors has uncovered novel functions in biology for gaseous ligands. ORGN 3 ATP-independent reversal of a membrane protein aggregate by a novel chaperone Shu-ou Shan, [email protected]. Department of Chemistry and chemical engineering, California Institute of Technology, Pasadena, California 91125, United States Protein homeostasis is essential
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