Abstract: The invention relates to a compound having general formula I, wherein: X represents CH2, C?O, C?S or CHOH, R1 represents an amino acid optionally substituted by one or more halogen atoms, or by one or more CF3 groups and n=0.1 or 2, or R1 represents a peptide containing two amino acids, each amino acid being optionally substituted by one or more halogen atoms, or by one or more CF3 groups and n=0 or 1, or XR1 represent PO3H or SO3H and n=0.1 or 2; R2 represents H, XR1, an alkyl group at C1-C6, an aralkyl group at C1-C6 or an aryl group, whereby the alkyl, aralkyl and aryl groups can be substituted by an amine NH2, a carboxylic group COOH, one or more halogen atoms.

Abstract: The invention relates to a compound having general formula I, wherein: X represents CH2, C?O, C?S or CHOH, R1 represents an amino acid optionally substituted by one or more halogen atoms, or by one or more CF3 groups and n=0.1 or 2, or R1 represents a peptide containing two amino acids, each amino acid being optionally substituted by one or more halogen atoms, or by one or more CF3 groups and n=0 or 1, or XR1 represent PO3H or SO3H and n=0.1 or 2; R2 represents H, XR1, an alkyl group at C1-C6, an aralkyl group at C1-C6 or an aryl group, whereby the alkyl, aralkyl and aryl groups can be substituted by an amine NH2, a carboxylic group COOH, one or more halogen atoms.