Compound

Tautomeric composition in DМSОd₆, %, (48 h after dissolution)

lgK_T^*

E,E'-А

E,Z'-А

B

3a

6

51

43

?0.122

3b

6

53

41

?0.158

3c

9

54

37

?0.231

3d

9

56

35

?0.269

3e

10

61

29

?0.389

3f

10

63

27

?0.432

3g

11

72

17

?0.689

3h

13

80

7

?1.123