In cellular metabolism, the citric acid cycle (Krebs cycle) plays a crucial role in energy production. During one complete turn of the citric acid cycle, several high-energy compounds are generated, including NADH and FADH2. These compounds are subsequently used in the electron transport chain to produce ATP through oxidative phosphorylation. Consider the following statement:
Which of the following compounds is not produced directly during a single turn of the citric acid cycle?