Compounds No

R

Molecular formula

Melting point (˚C)

Color

Yield (%)

6a

H

C23H18N4S

252

White

76

6b

NO2

C23H17N5O2S

260 - 266

Dark yellow

68

6c

CF3

C24H17F3N4S

220

White

70

6d

Cl

C23H17ClN4S

248

White

66

6e

CH3

C24H20N4S

250

White

78