Unnatural amino acids (UAAs) and their derivatives are an essential and ubiquitous class of molecules, playing a crucial role as key motifs in a wide range of biologically relevant natural products, pharmaceutical agents, agrochemicals, and materials. UAAs are pivotal in expanding the scope of protein engineering and drug design due to their non-native side chains, which impart novel properties to peptides and proteins. UAAs can drastically alter the properties of a molecule by altering its conformation, reactivity, and interaction with biological targets. Their unique functionalities enable the design of molecules with enhanced specificity for receptors or altered metabolic stability, making them essential tools for creating innovative therapeutics. The advancement of therapeutics to treat many diseases, such as cancer, COVID-19, and metabolic disorders, is increasingly focusing on targeted approaches. Protein drug conjugates (PDCs) represent a novel strategy in this endeavor, offering the potential to direct treatments to specific disease markers with high precision, thus minimizing off-target effects and maximizing therapeutic efficacy. Central to developing the next generation of PDCs is incorporating UAAs into peptides, enabling the fine-tuning of pharmacological properties, including selectivity, potency, stability, and bioavailability. Our research contributes to this field by presenting a method that facilitates the synthesis of UAAs, setting the stage for enhanced PDCs.