We use 2-mercaptobenzoxazole to study the notion of vibronic fine structure fingerprints in near-edge X-ray absorption fine structure (NEXAFS). It is shown that connected and non-connected carbons in the phenyl ring of the 2-mercaptobenzoxazole molecule give mutually similar excitation patterns and patterns similar to the one in free benzenewas while the 5-ring carbon is distinctly different in this respect. The simulated vibronic bands give an unambiguous assignment of the full NEXAFS spectrum at the carbon K-edge.