441a Biosynthesis of Nitramines

Vladimir Gilman¹, Michael Cushman¹, Thomas K. Wood², Edwin Jahngen³, Jimmie Oxley⁴, Randall J. Cramer⁵, and Brooke Jones⁶. (1) Infoscitex Corporation, 303 Bear Hill Road, Waltham, MA 02451, (2) Artie McFerrin Department of Chemical Engineering, Texas A&M University, 200 Jack E. Brown Building, MS 3122, College Station, TX 77843-3122, (3) Department of Chemistry, University of Massachusetts Lowell, One University Avenue, Lowell, MA 01854, (4) Department of Chemistry, University of Rhode Island, 51 Lower College Rd., Kingston, RI 02881, (5) IHDIV/NSWC, 101 Strauss Avenue, Indian Head, MD 20640, (6) BAE SYSTEMS Ordnance Systems Inc, Holston Army Ammunition Plant, Kingsport, TN 37660

Nitro-energetic compounds are widely used by the U.S. military as key components of contemporary weapons. However, production of nitro-energetics involves the use of highly concentrated hot nitric and sulfuric acids, results in the emission of nitrogen oxides, and is also a potential health hazard. The development of an alternative process for producing nitro-energetic compounds under milder conditions, in an environmentally friendly manner, and in higher yields would be a vast economic saving and improve the quality of life in the surrounding communities.

The new technological process will include several major stages, including microbial production, isolation and purification, quality control. Usage of aggressive, concentrated inorganic acids will be eliminated, while the need for organic solvents will be greatly reduced. Improved microorganisms will be produced for the synthesis of targeted compounds. The microbial process will essentially be a conversion of the precursors of the energetic ingredients into their nitrated forms (which are water insoluble) in water-based medium in a bioreactor supplied with peroxynitrite as a nitration agent. The driving force of the microbial nitration will be the need for microorganisms to detoxify their habitats from peroxynitrite by reacting it with precursors of EM. The capability of the microorganisms to perform such a nitration will be evolved by mutagenesis and exposure to selective pressure in the form of elevated concentration of peroxynitrite. This process can also be considered as biocatalytic nitration of EM precursors with microorganisms serving as the catalyst. The process will employ evolutionary-established, highly regioselective microorganisms. Thus, downstream processing will be facilitated due to lower isomeric diversity of the microbially-produced nitro-energetics. Generation of the EM in microbial cultures, as well as some initial insights into the product isomeric purity, will be confirmed by analysis (HPLC, LC, GC, DSC, NMR and/or similar methods). While the proposed program has a strong scientific basis, technical implementation may present difficulty. Therefore, an initial program aimed at concept demonstration is proposed. Should this proof-of-concept stage be successful, a continuation stage of the program will be devised and proposed based on data obtained.

It is anticipated that the reduction of the proposed technology to practice will have many beneficial impacts on Department of Defense end-users. Most significant of these are: 1) environmental burdens, along with associated costs, will be reduced significantly, and 2) energetic product quality, and potentially yield, will be improved.