| abstract |
A process for the preparation of a compound of formula (III): ** Formula ** or one of its salts, comprising the step of reacting a compound of formula (II): ** Formula ** or one of its salts , with a sulfonating agent, in which: Q represents a disulfide group selected from alkyl disulfide, phenyl disulfide, ortho- or paranitrophenyl disulfide, 2,4-dinitrophenyl disulfide, pyridyl disulfide, nitropyridyl disulfide; E represents a linear or branched alkyl that carries 1 to 4 carbon atoms; F is absent, or F and R1, together with the carbon atom to which they are attached, can form a three to seven membered cycloalkyl group; G is absent; and R1 is -H or a linear or branched alkyl bearing 1 to 4 carbon atoms. |