Table 3. 1H NMR assignment of critical hydrogen positions for lanosterol and parkeol, compared with reference values

 

Hydrogen

d (–OAc)*

d (–OH)

d measured

Lanosterol

H-18(3)

0.687

0.687

0.690

Parkeol

H-18(3)

0.644

n.a.

0.645

 

 

 

 

 

Lanosterol

H-30(3)

0.870

0.874

0.875

Parkeol

H-30(3)

0.736

n.a.

0.738

 

 

 

 

 

Lanosterol

H-7/H-11

n.a.

n.a.

2.00–2.04

Parkeol

H-12a

2.071

n.a.

2.06–2.07

Parkeol

H-8b

2.165

n.a.

2.17–2.18

 

 

 

 

 

Lanosterol

H-24

5.10

5.10

5.10

Parkeol

H-24

5.099

n.a.

5.10

 

 

 

 

 

Lanosterol

No equivalent

 

 

 

Parkeol

H-11

5.228

n.a.

5.23

n.a., not available.

*All d values are reported in ppm. Reference values are from Hart et al. [Hart, E. A., Hua, L., Darr, L. B., Wilson, W. K., Pnag, J. & Matsuda, S. P. T. (1999) J. Am. Chem. Soc. 121, S1–S7] and Goad and Akihisa [Goad, L. J. & Akihisa, T. (1997) Analysis of Sterols (Chapman & Hall, London)].