Define a main chain consisting of ten atoms labeled as follows: C1, N2, C3, C4, N5, C6, C7, N8, C9, and C10. In this structure, double bonds are present between N2 and C3, N5 and C6, and N8 and C9, forming imine linkages.
- At C1: Two substituents are attached, a carboxyl group (-COOH) and a 4-aminobutyl group (a four-methylene chain terminating in an amino group, -NH2).
- At C3: A hydroxyl (-OH) group is attached.
- At C4: A -CH2-SH group is attached, consisting of a methylene bridge linked to a thiol group.
- At C6: A hydroxyl (-OH) group is present.
- At C7: A secondary alcohol substituent (-CH(OH)CH3) is attached. Specifically, this group features a methine carbon that bears both a hydroxyl group (-OH) and a methyl group (-CH3).
- At C9: A hydroxyl (-OH) group is attached.
- At C10: Two substituents are present, an amino group (-NH2) and a 1-methylpropyl group (-CH(CH3)CH2CH3).