Research

My research focuses on the enantioselective synthesis of organic molecules isolated from natural sources. In particular, we have been investigating the synthesis of secondary metabolites isolated from the myxobacterium Sorangium cellulosum. Two such metabolites are the ripostatins and the chivosazols.

Myxobacteria live prefentially in soil, rotting plant material, dung and bark of living and dead trees. They have interesting motility features in that they move by gliding or creeping over the surface. Under starvation conditions, an even more unique behavior is observed in which the cells start to aggregate and pile up to produce fruiting bodies

myxobacteria myxobacteria: fruiting bodies

The Ripostatins, first isolated in 1996, have been reported to act as bacterial RNA polymerase inhibitors and do not show cross resistance to rifampicin, the antibiotic commonly used to treat tuberculosis.

Ripostatin

Chivosazols, also discovered in strains of Sorangium cellulosum have interesting architectural features from a synthetic standpoint, and show activity against yeasts and filamentous fungi.

Chivosazol

Progress toward the total synthesis of these two families of molecules is the major focus of our research efforts, as well as the synthesis of structural analogs for investigations into mechanism of action and structure-activity relationships.

Publications

  1. "Evaluation of a Chiral Aryl Auxiliary Design for Sulfur: Construction of Auxiliary-Modified Reagents and Stereoselection in Sulfoxide Formation," C. S. Swindell, F. R. Blase, and P. J. Carroll, Tetrahedron Letters 1990, 31, 5405-5408.
  2. "Evaluation of a Chiral Aryl Auxiliary Design for Sulfur: Regio- and Diastereoselective Conjugate Additions to Auxiliary-Modified Allylic Sulfoxide Reagents," C. S. Swindell, F. R. Blase, D. S. Eggleston, and J. Krause, Tetrahedron Letters 1990, 31, 5409-5412.
  3. "Tremorgenic Indole Alkaloids. 9. Asymmetric Construction of an Advanced F-G-H Ring Lactone Precursor for the Synthesis of Penitrem D," A. B. Smith, III, E. G. Nolan, Jr., R. Shirai, F. R. Blase, M. Ohta, N. Chida, R. A. Hartz, D. M. Fitch, W. M. Clark, P. A. Sprengeler, Journal of Organic Chemistry, 1995, 60, 7837-7848.
  4. "An Ullmann Ether Reaction Involving an Alkynyl Substrate: A Convergent Route to a Combretastatin Intermediate," F. R. Blase, K. Banerjee, Synthetic Communications, 1995, 25(20), 3187-3197.
  5. "Synthesis of ±-Unsubstituted Aldol Adducts Utilizing Enantiomerically Pure Ź-Keto Ą-Dioxolane Sulfoxides," F. R. Blase, H. Le, Tetrahedron Letters, 1995, 36, 4559-4562.
  6. "Synthesis and Use of a Substrate for the Detection of Isopeptidase Activity," A. G. Loewy, J. K. Blodgett, F. R. Blase, M. H. May, Analytical Biochemistry, 1997, 246, 111-117.
  7. “ Tremorgenic Indole Alkaloids. Studies Directed toward the Assembly of the A, F, and I Rings of Penitrem D: Observation of an Unexpected Stereochemical Outcome” Amos B. Smith, III, Naoki Kanoh, Noriaki Minakawa, Jon D. Rainier, Frances R. Blase, and Richard A. Hartz, Organic Letters, 1999, 1, 1263-1266.
  8. „Photodissociation of CH3OCl to CH3O + Cl at 248 nm.” Krisch, M. J.; McCunn, L. R.; Takematsu, K.; Butler, L. J.; Blase, F. R.; Shu, J. Journal of Physical Chemistry, 2004, 108, 16501656.