Wavenumber (cm⁻¹)

Assignments

2925

C-H or C=C stretch, presence of aromatics

2663, 2554

SH stretch

1717

C=O stretch

1651, 1634

C=O stretch, presence of aromatics (lactam ring)

1575, 1558

C=C, C=N stretching, N-H (Nitro) deformation

1384

C-H and/or 0-H deformation and/or C-0 stretch

1298, 1195, 1132

C-H or 0-H bending, C=O stretch