David L. Coffen
Hoffmann-La Roche
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Publication
Featured researches published by David L. Coffen.
Journal of the American Oil Chemists' Society | 1994
Hubert Maehr; Gladys Zenchoff; David L. Coffen
Commercially available fish oils with n−3 fatty acid contents ranging from 29 to 34% were converted enzymically, with Amano P lipase, to mixtures of glycerides with n−3 fatty acid contents ofca. 50%, in weight recovery yields of 23–50%, depending upon extraction procedures. Glyceride mixtures with n−3 fatty acid contents above 70% were obtained in yields of 14–21%. The processes are based on the relative stability of the ester linkages that involve n−3-fatty acyl groups and the regioselectivity of the enzyme toward acyl groups at the 1,3-positions of glycerol.
Bioorganic & Medicinal Chemistry | 1994
David L. Coffen; Masami Okabe; Ruen Chu Sun; Seoju Lee; George W. Matcham
(R)-alpha-Methyl-3-pyridinebutanamine (5) was required as a key intermediate for production of the PAF antagonist [(R)-(E,E)-5-(4-methoxyphenyl)-N-1- methyl-4-(3-pyridinyl)butyl-2,4-decadienamide (1). A method meeting the requirements of technical simplicity and economic viability was developed using an aminotransferase ex. B. megaterium to catalyze a kinetic resolution of racemic alpha-methyl-3-pyridinebutanamine (3). 5-(3-Pyridinyl)-2-pentanone (4) produced from the (S)-enantiomer, with co-generation of alanine, is recycled by catalytic reductive amination.
Journal of Organic Chemistry | 1988
Masami Okabe; Ruen Chu Sun; Steve Tam; Louis J. Todaro; David L. Coffen
Journal of Organic Chemistry | 1992
Alan Schwartz; Pradeep B. Madan; Erno Mohacsi; Jay Philip O'brien; Louis J. Todaro; David L. Coffen
Journal of Organic Chemistry | 1990
Panos Kalaritis; Ronald W. Regenye; John Joseph Partridge; David L. Coffen
Journal of the American Chemical Society | 1978
Hans Maag; John F. Blount; David L. Coffen; Thomas V. Steppe; Frederick Wong
Journal of Organic Chemistry | 1971
David L. Coffen; D. G. Korzan
Journal of Organic Chemistry | 1987
Jefferson Wright Tilley; David L. Coffen; Beatrice Schaer; Joan Lind
Journal of Organic Chemistry | 1984
David L. Coffen; Beatrice Schaer; Fred T. Bizzarro; Julia B. Cheung
Journal of Organic Chemistry | 1978
John F. Blount; David L. Coffen; David A. Katonak