Optically active compound production using immobilized enzymes in organic solvents

In cold alcoholic alkali the optically active compound I from Tigaso oil undergoes a rapid reaction which involves loss of its conjugated carbonyl system, and a large change, with inversion, of its optical rotation. The reaction is interpreted as a cyclization and the product is provisionally formulated as a bicyclononane derivative IIa. In hot alcoholic alkali, IIa is not the final product ; the bicyclic compound undergoes further reaction to give a mixture in which the unsaturated monocyclic triketone VII (R=C16H31) appears to predominate, but which probably consists of a mixture of VII and VIII (R=C16H31). These can be hydrogenated to a mixture of saturated monocyclic triketones VII and VIII (R =C16H33). The same hydrogenated triketones are obtained if IIa is first hydrogenated and then heated with alcoholic alkali. These triketones are optically active and by oxidation with hypobromite, or with permanganate and then hypobromite, yield bromoform and the chemically homogeneous tribasic acid IX, which still retains optical activity. The isolation of the saturated hydroxydiketone IIb in 4 per cent, yield from hydrogenated Tigaso oil suggests that 11% is present to that extent in the original oil.

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Use of enzymes as catalysts to promote key transformations in organic synthesis

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1989.0069 ◽

1989 ◽

Vol 324 (1224) ◽

pp. 577-587 ◽

Cited By ~ 24

Keyword(s):

Organic Synthesis ◽

Large Scale ◽

Immobilized Enzymes ◽

Building Blocks ◽

Optically Active ◽

The Past ◽

Small Proteins ◽

Areas Of Interest ◽

Oxidation Of Benzene ◽

Reduction Of Ketones

The field of biotransformations has developed rapidly over the past eight years. The use of esterases and lipases is now widespread; these enzymes are of particular importance in the production of optically active building blocks for organic synthesis as well as in large-scale processes involving the transesterification of fats. The latter area (i.e. the catalysis of esterification processes) has stimulated research into the properties of immobilized enzymes and the use of enzymes in low-water systems. In related work, enzymes have been used for the preparation of peptides and small proteins. Redox enzymes have been investigated extensively, particularly with regard to the stereocontrolled reduction of ketones to secondary alcohols. The methods for using commercially available enzymes of this type have become increasingly ‘userfriendly’. The controlled oxidation of hydrocarbon units is another area that has deserved increased attention. For example, oxidation of benzene and simple derivatives by Pseudomonas sp. has been researched by a number of U.K. groups. These recent advances in enzyme-catalysed reactions (using both whole-cell systems and partly purified protein) for the transformation of unnatural substrates is discussed and some areas of interest for the future are outlined.

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Application of Lipase in Organic Solvents for the Preparation of Optically Active Terpene Alcohol Esters

Annals of the New York Academy of Sciences ◽

10.1111/j.1749-6632.1988.tb25835.x ◽

1988 ◽

Vol 542 (1 Enzyme Engine) ◽

pp. 235-239 ◽

Cited By ~ 9

Author(s):

KENJI SONOMOTO ◽

ATSUO TANAKA

Keyword(s):

Organic Solvents ◽

Optically Active

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