{"knowledge_schema": {"broad_category": "Chemistry \u2192 Organic Chemistry \u2192 Spectroscopy", "refinement": "This problem involves interpreting NMR and mass spectrometry data to deduce the structure and purity of a synthesized compound.", "specific_scope": "The focus is on understanding the implications of observed peaks in the 1H NMR spectrum and LC-MS analysis in relation to the structure of a peptide compound.", "goal": "Identify the reason for the observed spectral features, particularly the presence of two peaks for the same alpha-proton in the NMR spectrum."}, "summary": "In this scenario, the analysis of a synthesized peptide compound reveals two peaks in the 1H NMR spectrum corresponding to the same alpha-proton, which suggests the presence of two distinct environments for that proton. The equal integrals and similar chemical shifts indicate that these peaks are likely due to diastereoisomers rather than enantiomers or contamination. The LC-MS analysis supports this by showing two distinct peaks of equal intensity, both matching the expected compound. Therefore, the most likely explanation for these observations is that the crude compound exists as a mixture of diastereoisomers."}