Synthesis and Pharmacological Activities of Pyrano[2,3-d]pyrimidine and Pyrano[2,3-d]pyrimidine-5-one Derivatives as New Fused Heterocyclic Systems

Table 2

The cytotoxic activity of some compounds against human tumor cells.

Compounds	In vitro cytotoxicity IC50 (µg/ml)
	HePG2	HCT-116	PC3	MCF-7
5-FU
1
2			>100	>100
3
4
5
7a
7b		>100
8
9
10
11

IC50 (µg/ml): 1–10 (very strong), 11–20 (strong), 21–50 (moderate), 51–100 (weak), and above 100 (noncytotoxic); 5-FU = 5-fluorouracil.