Raman spectroscopy The Raman spectra of compound

The Raman spectra of Forskolin 1 and 2 both show identical vibration modes of the S–O bond [38] and [39] (see Fig. 8). The vibrations between 300 and 700 cm−1 (452 and 625 cm−1 peaks for 1, and 439, 467, 610 cm−1 peaks for 2) could be assigned to the ν2 and ν4 bending modes of the S–O bond, whereas the peaks around 1000 cm−1 (1055, 1096, and 1250 cm−1 peaks for 1, and 1037, 1083, 1108, and 1200 cm−1 peaks for 2) are from the ν1 and ν3 stretching of the S–O bond.