New and general strategies for the enantiospecific construction of molecules of medicinal interest (antivirals, antibiotics, antitumor agents, etc ) are important to the overall mission of the NIH. Described within this proposal are the design and development of easily-prepared, enantiomerically-pure molybdenum pi-complexes of unsaturated oxygen and nitrogen hetero- cycles (2H-pyran, 1,2-dihydropyridine, and others) to which a rich variety of substituents can be sequentially and easily attached in a regio-and stereocontrolled fashion. Demetallation after attachment of multiple substituents would provide enantiomerically-pure, substituted oxygen and nitrogen heterocycles. In principle, these pi-complexes function as enantiomerically-pure scaffolds for the rapid assembly of substituted heterocyclic systems of known or potential medicinal value. Therefore, successful achievement of this new strategy would introduce a novel method for the synthesis of important classes of heterocyclic organic compounds with demonstrated biological activity in a wide variety of assays (antiviral, antibiotic, etc). Also, within the context of this grant, a metal binding ligand will be attached to a polymer matrix and to that ligand enantiomerically-pure oxygen and nitrogen heterocyclic scaffolds will be attached. Protocols for the functionalization and demetallation of these polymer-bound enantiomerically-pure heterocyclic scaffolds will be explored. This 'enantiomerically-pure scaffold' strategy, if developed to its fullest potential, could hold great promise for rapid structure-activity- relationship studies of enantiomerically-pure substituted oxygen-and nitrogen heterocyclic systems using combinatorial robotics techniques.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
2R01GM043107-07A1
Application #
2022335
Study Section
Medicinal Chemistry Study Section (MCHA)
Project Start
1989-12-01
Project End
2001-03-31
Budget Start
1997-04-01
Budget End
1998-03-31
Support Year
7
Fiscal Year
1997
Total Cost
Indirect Cost
Name
Emory University
Department
Chemistry
Type
Schools of Arts and Sciences
DUNS #
042250712
City
Atlanta
State
GA
Country
United States
Zip Code
30322
Wong, Heilam; Garnier-Amblard, Ethel C; Liebeskind, Lanny S (2011) Organometallic enantiomeric scaffolding: a strategy for the enantiocontrolled construction of regio- and stereodivergent trisubstituted piperidines from a common precursor. J Am Chem Soc 133:7517-27
Coombs, Thomas C; Huang, Wenwei; Garnier-Amblard, Ethel C et al. (2010) Novel Substitutions of 1-Alkoxy- and 1-Arylsulfonyloxy-?-Allylmolybdenum Complexes. A Case for ?-Alkenyl Carbene Complexes as Intermediates. Organometallics 29:5083-5097
Cheng, Bo; Liebeskind, Lanny S (2009) Organometallic enantiomeric scaffolding. A molybdenum-mediated intramolecular nucleophilic ketalization-demetalation cascade. Total synthesis of (+)-(1R,2S,5S,7R)-2-hydroxy-exo-brevicomin. Org Lett 11:3682-5
Coombs, Thomas C; Zhang, Yongqiang; Garnier-Amblard, Ethel C et al. (2009) Organometallic enantiomeric scaffolding. Sequential semipinacol/1,5-""Michael-like"" reactions as a strategic approach to bridgehead-quaternary center aza[3.3.1]bicyclics: application to the total synthesis of (-)-adaline. J Am Chem Soc 131:876-7
Chen, Wenyong; Liebeskind, Lanny S (2009) A new reaction motif: ""homo-S(N)2'-like"" direct nucleophilic addition to neutral eta(3)-allylmolybdenum complexes. total synthesis of the antimalarial (+)-isofebrifugine. J Am Chem Soc 131:12546-7
Garnier, Ethel C; Liebeskind, Lanny S (2008) Organometallic enantiomeric scaffolding: general access to 2-substituted oxa- and azabicyclo[3.2.1]octenes via a Bronsted acid catalyzed [5 + 2] cycloaddition reaction. J Am Chem Soc 130:7449-58
Coombs, Thomas C; Lee 4th, Maurice D; Wong, Heilam et al. (2008) Practical, scalable, high-throughput approaches to eta3-pyranyl and eta3-pyridinyl organometallic enantiomeric scaffolds using the Achmatowicz reaction. J Org Chem 73:882-8
Arrayas, Ramon Gomez; Yin, Jingjun; Liebeskind, Lanny S (2007) The enantiomeric scaffold approach to highly functionalized 1-oxadecalines: enantio- and regiocontrolled [4 + 2] cycloadditions of 5-alkenyl-eta3-pyranylmolybdenum complexes. J Am Chem Soc 129:1816-25
Arrayas, Ramon Gomez; Liebeskind, Lanny S (2003) Eta3-pyranyl and eta3-pyridinyl molybdenum pi-complexes as chiral scaffolds for the enantioselective construction of substituted oxa- and aza[3.3.1]bicyclics: first enantio- and regiocontrolled [5+3] cycloaddition reactions. J Am Chem Soc 125:9026-7
Shu, Chutian; Liebeskind, Lanny S (2003) Enantiocontrolled synthesis of 2,6-disubstituted piperidines by desymmetrization of meso-eta-(3,4,5)-dihydropyridinylmolybdenum complexes. application to the total synthesis of (-)-dihydropinidine and (-)-andrachcinidine. J Am Chem Soc 125:2878-9

Showing the most recent 10 out of 17 publications