Compound | R1 | R2 | R3 | R4 |
E20 | H | H | H | H |
E21 | H | OCH3 | OCH3 | OCH3 |
E22 | H | H | N(CH3)2 | H |
E23 | H | H | Cl | H |
E24 | H | H | OCH3 | OCH3 |
E25 | H | H | OCH3 | H |
E26 | H | H | F | H |
E27 | Br | H | CH2CH(CH3)2 | H |
E28 | Br | H | OCH3 | H |
E29 | H | H | CH2CH(CH3)2 | H |