Maple syrup urine disease is due accumulation of
Phenylalanine
Tyrosine
Branched chain amino acids
Tryptophan
Maple syrup urine disease is also called branched-chain ketonuria The basic defect is deficient decarboxylation of branched-chain ketoacids.Ref: DM Vasudevan - Textbook of Biochemistry, 7th edition, page no: 230
Metabolism of protein and amino acid