PC Cleavable Linkers include a variety of products, most of which are biodegradable ADC linkers that can be used to synthesize antibody-conjugated drugs or catalyze a variety of click chemical reactions. PC Cleavable Linkers must meet a variety of challenging constraints, such as mild cracking conditions, the use of biological orthogonal reagents, high yields at low concentrations, and the ease of eliminating excess reagents and by-products.