Abstract: A compound selected from the group consisting of a compound of the formula wherein A is selected from the group consisting of hydrogen, alkyl of 1 to 6 carbon atoms and --NO.sub.2, E is --O-- or a covalent bond, n is an integer from 1 to 12, R.sub.1 and R.sub.2 are individually alkyl of 1 to 6 carbon atoms or taken together with the nitrogen to which they are attached form an optionally unsaturated 5 to 6-member ring of the formula --NX and X is selected from the group consisting of oxygen, sulfur, methylene and >N--R', R' being hydrogen or an alkyl of 1 to 6 carbon atoms, and their pharmaceutically acceptable acid addition salts useful to inhibit --NO synthase.