The design of artificial structures such as Peptide Nucleic Acids (PNAs) capable of recognizing nucleic acids has attracted much attention. We report herein the design of l-homoserine derivatives bearing diaminotriazine groups as artificial nucleobase capable of pairing to thymine. We set up an original six-step synthetic route (45% overall yield) that enables the functionalization of the nucleobase analogue. Furthermore, we show that these modified amino acids can be incorporated, by solid-phase peptide synthesis, into alternate and homopolymer α-PNAs, thereby giving access to α-PNAs in which the nucleobase analogue bears functional groups that may prove useful for the multi-point recognition of nucleic acids.