Aminoacid derivatives as antihypertensives

A compound of the formula:

• ##STR14## wherein n is 0 or 1
• R is lower alkyl, phenyl lower alkyl, hydroxyphenyl lower alkyl, hydroxy lower alkyl, aminoloweralkyl, guanidino lower alkyl, imidazoyl lower alkyl, indolyl lower alkyl, mercapto lower alkyl, lower alkyl mercapto lower alkyl;
• R.sub.3 and R.sub.4 may be connected together to form an alkylene bridge of from 2 to 4 carbon atoms or an alkylene bridge of from 2 to 3 carbon atoms and one sulfur atom;
• X is NR.sup.5, S where R.sup.5 =H or lower alkyl;
• R.sub.1 is hydrogen, lower alkyl, phenyl lower alkyl or phenyl or substituted phenyl wherein the substituent is halo, lower alkoxy or lower alkyl;
• R.sub.2 is hydrogen, lower alkyl, phenyl lower alkyl, or phenyl or substituted phenyl wherein the substituent is halo, lower alkoxy or lower alkyl and pharmaceutically acceptable salts thereof.