Compound

R

Initial aldose

Form in crystals

Tautomeric composition (%) in D2O

Form B

Form A

Form C

3a

H

L-Arabinose

E

65

5

30

3b

H

D-Xylose

E

50

10

40

3c

H

D-Ribose

E

70

10

20

3d

CH2OH

D-Galactose

B

70

5

25

3e

CH2OH

D-Glucose

B

85

5

10

3f

CH2OH

D-Mannose

B

75

5

20