The invention concerns a C-glycoside compound of formula (I); wherein: n is equal to 1 or 2; Y represents H or halogen; X is an alkyl chain bearing at least one amino, amide, acid, ester, carbonyl, alcohol, aryl function or a carbonyl, ester amide, amino, alcohol group; the R's, identical or different, represent a OH or OR' group where R' is an alkyl, benzyl, benzoyl, acetyl, pivaloyl, trialkylsilyl, tertiobutyldiphenylsilyl group or one or more sugars; R1 represents OR', NR''R''', N3, or a phthalamide with R'' and R''', identical or different, represent H or an alkyl, aryl, benzyl, benzoyl, acetyl, alkoxycarbonyl, allyloxycarbonyl, benzyloxycarbonyl group; R2 represents H or halogen or a OH, OR, NR''R''' or N3 group, as well as derivatives thereof in physiologically or pharmaceutically acceptable base, mineral or organic acid-addition salt, hydrate or solvate form. The invention is useful for preparing C-glycoside compounds or C-glycoconjugates applicable in particular in cosmetology, medical imagery, immunology for treating cancer, diabetes, hypertension.