The present invention provides a bioconjugation method and compounds for use therein. The bioconjugation method comprises the step of conjugating a biological molecule containing a first unsaturated functional group with a payload comprising a second unsaturated functional group, wherein the first and second unsaturated functional groups are complementary to each other such that conjugation is a reaction of said functional groups via a Diels-Alder reaction which forms a cyclohexene ring.

A flavour composition comprising a compound according to the formula (I) or edible salts thereof, ##STR00001##
wherein R.sub.1 is alkyl residue containing 6 to 20 carbon atoms, or an alkene residue containing from 9 to 25 carbon atoms with 1 to 6 double bonds, R.sub.1 together with the carbonyl to which it is attached is a residue carboxylic acid, and NR.sub.2R.sub.3, in which R.sub.3 is H or together with R.sub.2 and the N-atom to which they are attached, a 5-membered ring, is a residue of an amino acid, in particular proteinogenic amino acid, ornithine, gamma-aminobutyric acid or beta alanine, or a 1-amino cycloalkyl carboxylic acid.

A flavour composition comprising a compound according to the formula (I) or edible salts thereof, ##STR00001##
wherein R.sub.1 is alkyl residue containing 6 to 20 carbon atoms, or an alkene residue containing from 9 to 25 carbon atoms with 1 to 6 double bonds, R.sub.1 together with the carbonyl to which it is attached is a residue carboxylic acid, and NR.sub.2R.sub.3, in which R.sub.3 is H or together with R.sub.2 and the N-atom to which they are attached, a 5-membered ring, is a residue of an amino acid, in particular proteinogenic amino acid, ornithine, gamma-aminobutyric acid or beta alanine, or a 1-amino cycloalkyl carboxylic acid.

A flavour composition comprising a compound according to the formula (1) or edible salts thereof, ##STR00001##
wherein R.sub.1 is an alkyl residue containing 6 to 20 carbon atoms, or an alkene residue containing from 9 to 25 carbon atoms with 1 to 6 double bonds, R.sub.1 together with the carbonyl group to which it is attached is a residue of a carboxylic acid, and NR.sub.2R.sub.3, in which R.sub.3 is H or together with R.sub.2 and the N-atom to which they are attached, a 5-membered ring, is a residue of an amino acid, in particular a proteinogenic amino acid, ornithine, gamma-aminobutyric acid or beta alanine, or a 1-amino cycloalkyl carboxylic acid.

A flavour composition comprising a compound according to the formula (1) or edible salts thereof, ##STR00001##
wherein R.sub.1 is an alkyl residue containing 6 to 20 carbon atoms, or an alkene residue containing from 9 to 25 carbon atoms with 1 to 6 double bonds, R.sub.1 together with the carbonyl group to which it is attached is a residue of a carboxylic acid, and NR.sub.2R.sub.3, in which R.sub.3 is H or together with R.sub.2 and the N-atom to which they are attached, a 5-membered ring, is a residue of an amino acid, in particular a proteinogenic amino acid, ornithine, gamma-aminobutyric acid or beta alanine, or a 1-amino cycloalkyl carboxylic acid.

The present invention relates to a novel process for preparing substituted cyclohexane amino acid esters and spiroketal-substituted cyclic keto-enols, and to novel intermediates or starting compounds that are passed through or used in the process according to the invention.

The present invention relates to a novel process for preparing substituted cyclohexane amino acid esters and spiroketal-substituted cyclic keto-enols, and to novel intermediates or starting compounds that are passed through or used in the process according to the invention.

A flavour composition comprising a compound according to the formula (I) or edible salts thereof, ##STR00001##
wherein R.sub.1 is an alkyl residue containing 6 to 20 carbon atoms, or an alkene residue containing from 9 to 25 carbon atoms with 1 to 6 double bonds, R.sub.1 together with the carbonyl group to which it is attached is a residue of a carboxylic acid, and NR.sub.2R.sub.3, in which R.sub.3 is H or together with R.sub.2 and the N-atom to which they are attached, a 5-membered ring, is a residue of an amino acid, in particular a proteinogenic amino acid, ornithine, gamma-aminobutyric acid or beta alanine, or a 1-amino cycloalkyl carboxylic acid.

A flavour composition comprising a compound according to the formula (I) or edible salts thereof, ##STR00001##
wherein R.sub.1 is an alkyl residue containing 6 to 20 carbon atoms, or an alkene residue containing from 9 to 25 carbon atoms with 1 to 6 double bonds, R.sub.1 together with the carbonyl group to which it is attached is a residue of a carboxylic acid, and NR.sub.2R.sub.3, in which R.sub.3 is H or together with R.sub.2 and the N-atom to which they are attached, a 5-membered ring, is a residue of an amino acid, in particular a proteinogenic amino acid, ornithine, gamma-aminobutyric acid or beta alanine, or a 1-amino cycloalkyl carboxylic acid.

A flavour composition comprising a compound according to the formula (I) or edible salts thereof,

##STR00001##

wherein
R.sub.1 is an alkyl residue containing 6 to 20 carbon atoms, or an alkene residue containing from 9 to 25 carbon atoms with 1 to 6 double bonds, R.sub.1 together with the carbonyl group to which it is attached is a residue of a carboxylic acid, and NR.sub.2R.sub.3, in which R.sub.3 is H or together with R.sub.2 and the N-atom to which they are attached, a 5-membered ring, is a residue of an amino acid, in particular a proteinogenic amino acid, ornithine, gamma-aminobutyric acid or beta alanine, or a 1-amino cycloalkyl carboxylic acid.