A derivative of estradiol substituted in position 6 of the formula: ** Formula ** in which ring "a" is selected from the group consisting of ** Formula ** R1, R2, R3 and R4 are independently hydrogen, C1-C6 alkyl, halo, a sulfate, a glucuronide, -OH, a bulky group, aryl, cycloalkyl, heteroaryl, heterocycloalkyl, -N (CH2) n； a phosphate group, and a phosphinate group； R11 is selected from the group consisting of H, C1-C6 alkyl, halogen, a sulfate, a glucuronide, -SO2NH2, -COOH, -CN, -CH2CN -, - NHCN-, -CHO,>； = CHOCH3, salt -CO, -OSO2alkyl, -NH2, and -NHCO (CH2) n； X is selected from the group consisting of C1-C12 alkyl, C2-C12 alkenyl, C2-C12 alkynyl, halogen, glucuronide, -NH2, -SO2NH2, -COOH, -CN, -CH2CN, -NHCN, -CHO, salt - COO, -OSO2alkyl, -SH, -SCH3, -CH [(CH2) nCH3] COOCH3, - (CH2) mCOOCH3, - (CH2) mO-CH3, - (CH2) mO- (CH2) nCH3, (CH2) mS -CH3, - (CH2) mS- (CH2) nCH3, - (CH2) m-NH- (CH2) nCH3, -C2-C8 alkenyl- O- (CH2) nCH3, -C2-C8 alkenyl-S- (CH2 ) nCH3, -C2-C8 alkenyl-N- (CH2) nCH3, -C2-C8 alkynyl-O- (CH2) nCH3, -C2-C8 alkynyl-S- (CH2) nCH3, -C2-C8 alkynyl-N- (CH2) nCH3, - (CH2) m-OH, - (CH2) m-NH2, - (CH2) mO-NH2, - (CH2) mS-NH2, - NH (CH2) mCH3, -NH (CH2) mOCH3 , -NH (CH2) mCHOH-COOH, -N (CH3) 2, - (CH2) m (NH) CH2OH, -NHCOOH, - (CH2) mNHCOOH, -NO2, -SCN, -SO2alkyl, -B (OH) 2, - (CH2) m N (CH3) -SO2-NH3, - (CH2) m-NH-SO2-NH2, -NHC (>； = S) CH3, and -NHNH2； Y is selected from hydrogen,>； = O, -OCO (C1-C20 alkyl) and -OH； and Z is H or methyl； in which m is an integer between 0 and 20, n is an integer between 0 and 8, the symbol - - - - represents a single or double bond capable of forming a keto group in position 3 and / or 17； and the symbol represents any type of link with indifference to stereochemistry； and enantiomers, other stereochemical isomers, hydrates, solvates, tautomers and pharmaceutically acceptable salts of said compounds, for use in the prevention of demyelination and / or intensification of the remyelination of an axon of a nerve cell
