Fig. 2.

Spectroscopic identification of 4-hydroxyphenylacetonitrile sulfate isolated from P. rapae feces. Structure and numbering system of 4-hydroxyphenylacetonitrile sulfate are depicted. The signals in NMR, MS, and IR spectra were assigned as follows: ¹H NMR (D₂O, 400 MHz): δ 3.94 (s, H2); 7.32 (“d”,J = 9 Hz, H3′+ H5′); 7.43 (“d”,J = 9 Hz, H2′+ H6′). ¹³C NMR (D₂O, 100 MHz): δ 23.1 (C2); 120.8 (C1); 122.9 (C3′ + C5′); 129.3 (C1′); 130.3 (C2′ + C6′); 151.5 (C4′). Selected heteronuclear multiple bond correlation interactions are indicated by arrows. MS, m/z: 463 [M²⁺K]^–; 447 [M²⁺Na]^–; 212 [M]^–; 132 [M-SO₃]^–. MS/MS confirmed m/z 132 as a fragmentation product of m/z 212. IR, ν_max: 2,246 cm^–1 (w, CN). UV, λ_max: 208 nm (100%), 260 nm (4%).