This invention relates to a chemistry branch, particularly to the field of compounds' organic synthesis that belongs to the aromatic bicyclic or naphthalene category, used in the detection of amyloid sheets. These new naphthalene derivatives have a general formula:Where R represents mutually independent groups.In I: R1: -alkylenyl-C(O)NH-alkylenyl-R3, -alkylenyl-C(O)O-R4; R3: -COOH, -OH, - SH, -NH2, -alkyl-NH, -alkyl-N-dithiocarbamate alkaline earth metal salts. R4: succinimidyl group. R2: -H, -alkyl. The term "alkyl" is characterized by a linear or branched aliphatic chain, hydrogen and saturated carbon atoms, comprising a methyl, ethyl, n-propyl, iso-propyl, n-butyl or iso-butyl groups. The term "alkylenyl" refers to a divalent analog of a linear or branched alkyl group, preferably ethylenyl (CH2CH2) or butylenyl (CH2CH2CH2CH2) radicals.In II: R1: -alkyl, and R2 is -alkylenyl-O-arylsulfonate, -alkylenyl-halide, -CH(O), alkylenyl-NH2, -alkylenyl-NH-alkyl, -alkylenyl-alkyl-N-dithiocarbamate salts such as cesium, potassium or sodium. The term "alkyl" is characterized by a linear or branched aliphatic chain, hydrogen and saturated carbon atoms, preferably methyl, ethyl, n-propyl, iso-propyl, n-butyl or iso-butyl. The term "alkylenyl" refers to a divalent analog of a linear or branched alkyl group, preferably propylenyl (-CH2CH2 CH2) radical. The term halide refers to fluorine, bromine or iodine.or,In II: R1: -alkylenyl-halide, -alkylenyl-O-arylsulfonate and R2: -halide, -alkylenyl-O-arylsulfonate, -alkylenyl-O-alkylsulfonate, -alkylenyl-halide, -CH(O), -HC=C(CN)2, - HC=CHNO2, -alkylenyl-NH2, -alkylenyl-NH-alkyl, -alkylenyl-alkyl-N-dithiocarbamate salts such as cesium, potassium or sodium. The term "alkylenyl" refers to a divalent analog of a linear or branched alkyl group, preferably propylenyl (-CH2CH2 CH2) radical. The term halide refers to fluorine, bromine or iodine.These compounds are neutral, lipophilic and have low molecular weight and therefore they