Final answer:
The initial compound formed in the Maillard reaction is not detailed in the provided text. Additional information would be needed to accurately identify this compound.
Step-by-step explanation:
The compound generated at the initial step of the Maillard reaction is not explicitly mentioned in the text provided, but the Maillard reaction, in general, starts with a reaction between reducing sugars and amino acids, which forms a complex mixture of poorly characterized molecules responsible for a range of aromas and flavors. In the references provided, various chemical reactions and mechanisms are described, including various arylation processes catalyzed by palladium and copper, which involve complex molecules such as uracil and adenine derivatives. However, none of these specifically detail the initial compound formed in a Maillard reaction. To answer the question about the Maillard reaction's initial compound more accurately, additional information outside of the text provided would be needed.