S. No.

Entry

R1

R2

R3

R4

R5

R6

9 Yield (%)a

1

a

H

OH

H

H

H

H

88

2

b

H

OH

H

OCH3

H

H

89

3

c

H

OH

H

H

OCH3

H

90

4

d

H

OH

H

H

OH

H

88

5

e

H

OH

OCH3

H

OCH3

H

89

6

f

OH

OH

H

H

H

H

75, 89b

7

g

OH

OH

H

OCH3

H

H

70, 85b

8

h

OH

OH

H

H

OCH3

H

75, 90b