C20 ( H nhẹ)

1 C1 

2 C2 

3 C3 

4 C4 

5 C5 

6 C6 

7 C7 

8 C8 

9 C9 

10 C10 

11 C11 

12 C12 

13 C13 

14 C14 

15 C15 

16 C16 

17 C17 

18 C18 

19 C19 

20 C20 ( H nhẹ) 

21 C21 ( H+ ) 

22 C22 

23 C23 

24 C24 

25 C25 

26 C26 

27 C27 

28 KO PHẢI CHAP 

29 C28 ( H nhẹ ) 

30 C29 ( H+ ) 

31 KO PHẢI CHAP 

32 C30 

33 C31 

34 C32 

35 KO PHẢI CHAP 

36 C33 

37 C34 

38 C35 

39 C36 

40 C37 

41 C38 

42 C39 

43 C40 ( H+ ) 