Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno

Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek

Nederlandse Organisatie Voor Toegepast

Nederlandse Organisatie Voor Et Al.

Antonius Kerkenaar

Diederik J Schmedding

Jan Berg

Ronald T Van Den Dool

A method for preparing thiol compounds, comprising: (1) reacting cysteine by a non-enzymatical addition reaction with a compound having the formula (R.sub.1)(R.sub.2)C.dbd.C(R.sub.3)--CO--R.sub.4 via an --S-- bridge to form a cysteine conjugate, wherein the symbols R.sub.1, R.sub.2, R.sub.3 and R.sub.4 represent hydrogen or an optionally saturated and/or heterogeneous hydrocarbon group or wherein a combination of two groups selected from the group consisting of R.sub.1, R.sub.3 and R.sub.4, together with the carbon atoms to which the groups are bonded, form an optionally saturated and/or heterogeneous hydrocarbon ring system of five or six members; and (2) reacting the cysteine conjugate so obtained in a concentration of &gt;1 mM conjugate with a microbial .beta.-lyase to form a thiol compound.

Method for preparing thiol compounds with bacterial .beta.-lyase

Method for preparing thiol compounds by coupling cysteine having the formula HS--CH.sub.2 --CH(NH.sub.2)COOH via and --S-- bridge to a hydrocarbon compound and subsequently reacting the cysteine conjugate obtained with .beta.-lyase to form the relevant thiol compounds. For instance it is possible to prepare the flavor p-mentha-8-thiol-3-one starting from pulegone as illustrated in the diagram below: ##STR1##

Method for preparing p-mentha-8-thiol-3-one

Bifunctional oligosaccharides, characterized by the formula ##STR1## wherein R.sub.1 represents a hydrogen atom, an alkyl group having 1-4 carbon atoms or an alkali metal, R.sub.2 represents a single bond or a divalent radical compound of monosaccharides and glc represents glucose, are obtained with the help of a specific microbial lyase cleaving the glucose-glucoronic acid bond in polysaccharides; said bifunctional oligosaccharides can be reacted with all kinds of products like proteins and drugs resulting in products having modified properties like solubility etc.

Bifunctional oligosaccharides and also active compounds derived therefrom

Method for controlling vascular withering diseases in plants, especially trees, such as controlling Dutch elm disease by a propylactic or curative treatment of plants with a systemic fungicide which inhibits sterol biosynthesis.

Growing community of inventors

Blaricum, Netherlands

Antonius Kerkenaar