Branched amides of L-aspartyl-d-amino acid dipeptides

An L-aspartyl-D-amino acid dipeptide amide of the formula ##STR412## and the physiologically acceptable cationic and acid addition salts thereof, wherein R.sup.a is methyl, ethyl, n-propyl or isopropyl;

• and
• R is a branched member selected from the group consisting of fenchyl, diisopropylcarbinyl, d-methyl-t-butylcarbinyl, d-ethyl-t-butylcarbinyl, di-t-butylcarbinyl, 2-methylthio-2,4-dimethylpentan-3-yl, ##STR413## where at least one of R.sup.3, R.sup.4, R.sup.5, R.sup.6 is alkyl having from one to four carbon atoms and the remainder are hydrogen or alkyl having from one to four carbon atoms, X is O, S, SO, SO.sub.2, C.dbd.O or CHOH;
• m is zero, 1, 2, 3 or 4, n and p are each zero, 1, 2 or 3 where the sum of n+p is not greater than 3 and the sum of the carbon atoms in R.sup.3, R.sup.4, R.sup.5 and R.sup.6 is not greater than six, and when both of R.sup.3 and R.sup.4 or R.sup.5 and R.sup.6 are alkyl they are methyl or ethyl, ##STR414## where one of R.sup.7, R.sup.8, R.sup.9 is alkyl having from one to four carbon atoms and the remainder are hydrogen or alkyl having from one to four carbon atoms and the sum of the carbon atoms in R.sup.7, R.sup.8 and R.sup.9 is not greater than six, ##STR415## where m and q are the same or different and each have the values previously defined for m, ##STR416## where each of R.sup.12 and R.sup.13 are methyl or ethyl, or R.sup.12 is hydrogen and R.sup.13 is alkyl having from one to four carbon atoms, Z is 0 or NH and t is 1 or 2, ##STR417## where w is 1, 2, 3 or 4, R.sup.14 and R.sup.16 are each alkyl having from one to four carbon atoms, R.sup.15 is hydrogen, OH, or alkyl having from one to two carbon atoms, where the sum of the carbon atoms in R.sup.14, R.sup.15 and R.sup.16 is not greater than six and when both of R.sup.14 and R.sup.15 are alkyl they are methyl or ethyl, and ##STR418## where R.sup.17 and R.sup.19 are alkyl having from one to four carbon atoms, R.sup.18 and R.sup.20 are hydrogen or alkyl having from one to two carbon atoms, taken separately, A is OH and B is hydrogen, OH or methyl and when taken together A and B are ##STR419## where the sum of the carbon atoms in R.sup.17, R.sup.18, R.sup.19 and R.sup.20 is not greater than six and when both of R.sup.17 and R.sup.18 or R.sup.19 and R.sup.20 are alkyl they are methyl or ethyl.