TOAC (“T-O-A-C”) is a cyclic, radical one of these compounds used as a spin label in EPR spectroscopy. Isotope-labeled versions of these compounds are used in SILAC (“SYE-lack”) experiments. Derivatives of one of these compounds react with boroxines (“bor-OCK-seens”) to form asymmetric Corey–Bakshi–Shibata catalysts. These compounds are conjugated onto Wang resins using coupling agents like benzotriazoles (10[1])or carbodiimides (“carbo-die-IM-mydes”) in Merrifield solid-phase synthesis. In that method, these compounds must be protected by groups like Boc (“bock”) and Fmoc (“F-mock”). These compounds are formed by treating an aldehyde with hydrogen cyanide then hydrolysis during the Strecker synthesis. Simple examples of these compounds can be formed by electrical discharges, (10[1])as demonstrated by Miller and Urey. For 10 points, name these building blocks for polypeptides. ■END■ (10[1])