New thiophene compounds of the formula: ##STR1## in which: X represents hydrogen, halogen, C.sub.1 -C.sub.5 alkyl or alkoxy or dialkylamino;n represents 1 or 2;a represents an integer of from 2 to 6;b represents 2 or 3;c represents 1 or 2, and is such that b+c=4;R.sub.1 and R.sub.2 represent hydrogen or (C.sub.1 -C.sub.5)alkyl, or together with the carbon atom to which they are bonded form a hydrocarbon ring containing from 3 to 6 carbon atoms; andR and R' represent hydrogen or (C.sub.1 -C.sub.5)alkyl, or together with the nitrogen atom to which they are bonded form a pentagonal or hexagonal heterocycle optionally containing an oxygen atom or a second nitrogen atom which may itself be substituted; and their physiologically tolerable salts.The products of the invention can be used therapeutically especially in the treatment of pathologies that are characterized by a loss of bone tissue.As new intermediate products used in the synthesis of the compounds I above defined, the amides of the formula: ##STR2## in which: X, n, a, b, c, R.sub.1, R.sub.2, R and R' are as above defined.