tokens: Studies with 20-epi analogues pointed out the importance of the carbon-20 position and led to the development of 20-methyl derivatives of VD .
folded_tokens: studies with 20-epi analogues pointed out the importance of the carbon-20 position and led to the development of 20-methyl derivatives of vd .
labels: O O B-other_organic_compound I-other_organic_compound O O O O O O O O O O O O O O B-other_organic_compound I-other_organic_compound O B-lipid O