Table 4 Structures and in vitro cytotoxic activities of indenopyrido[16]pyrimidine derivatives (4a-4j) 
Compound | R | IC50 ± SD (µM) |  | ||
|---|---|---|---|---|---|
A549 | MCF7 | SKOV3 | MRC-5 | ||
4a | H | 79.88 ± 2.81 | 91.72 ± 2.86 | 121.12 ± 11.4 |  > 100 |
4b | 2-OH | 193.77 ± 0.3 | 228.6 ± 12.97 | 528.88 ± 19.27 |  > 100 |
4c | 2-Cl |  > 1000 |  > 1000 |  > 1000 | N.D |
4 d | 2-Br |  > 1000 |  > 1000 |  > 1000 | N.D |
4e | 2-NO2 |  > 1000 |  > 1000 |  > 1000 | N.D |
4f | 4-F | 48.30 ± 4.12 | 37.90 ± 0.73 | 62.5 ± 2.6 | 98.3 ± 3.1 |
4 g | 4-Cl |  > 1000 |  > 1000 |  > 1000 | N.D |
4 h | 4-Br |  > 1000 |  > 1000 |  > 1000 | N.D |
4i | 2,4-di-Cl | 407.76 ± 27.57 | 504.36 ± 23.91 | 424.63 ± 5.05 |  > 100 |
4j | 3-OMe-4-OH |  > 1000 |  > 1000 |  > 1000 | N.D |
Cisplatin | – | 50.81 ± 3.10 | 61.56 ± 0.98 | 43.81 ± 3.79 |  |