Start with a central thioether sulfur as the symmetry point. On each side of this sulfur, attach the same fragment: a methylene linker followed by an imidic acid unit. 

In connectivity, each arm is -S-CH2-C(=NH)-OH. If both ends are identical, the overall chain is mirror-symmetric about the sulfur.

Now break the perfect symmetry at one terminus by substituting the imidic nitrogen's hydrogen with a tetralin ring system (a benzene ring fused to a cyclohexane). This makes that end -C(=N-Tetralin)-OH while the opposite end remains -C(=NH)-OH. The imidic nitrogen bonds to a carbon of the cyclohexane portion that is ortho to one of the fusion junctions, denoted as C1. Number sequentially around the peri carbons:

- traverse the cyclohexane portion C1-C2-C3-C4,
- then skip the fusion junction to enter the benzene portion C5-C6-C7-C8,
- reach the other fusion junction, and return to C1.

On the benzene portion at C6, place a primary amino group (-NH2).