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: Wherein 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: H, succinimidyl group, R2: —H,-alkyl. In II: R1: -alkyl, -alkylenyl-halide-alkylenyl-hydroxyl-alkylenyl-O-aryl, —O-alkylsulfonate alkylenyl, R2: -halide-alkylenyl-O-aryl, -alkylenyl-O-alkylsulfonate, -alkylenyl-halide-, —CH(O), —HC═C(CN)2, —HC═CHNO2, -alkylenyl-NH2, -alkylenyl-NH-alkyl, -alkylenyl-alkyl-N-dithiocarbamate alkaline salts. The terms “alkyl” and “alkylenyl” refer to linear or branched aliphatic chains, preferably from 1 to 4 carbon atoms and the term halide to fluorine, bromine or iodine. These compounds are neutral, lipophilic and have low molecular weight and therefore they cross the blood brain barrier and attach to the amyloid sheets. The present invention provides procedures for obtaining naphthalene derivatives with good yields, which can be practical, economical and adapted to a larger-scale manufacturing. We are unaware whether the compounds presented in this invention have been previously reported.