SPHK1/2 inhibition activity of compounds 1–25^a.

Compound	SPHK1 activity (% of Ctl)	SPHK2 activity (% of Ctl)	Compound	SPHK1 activity (% of Ctl)	SPHK2 activity (% of Ctl)
1	81.89 ± 7.24	83.33 ± 12.35	15	70.19 ± 14.18	79.37 ± 11.22
2	59.75 ± 4.14	25.40 ± 4.49	16	100.97 ± 17.64	113.49 ± 10.10
3	74.09 ± 9.27	122.22 ± 14.55	17	96.11 ± 8.93	79.37 ± 13.47
4	72.14 ± 14.96	58.20 ± 6.61	18	111.35 ± 14.48	35.71 ± 3.37
5	98.89 ± 9.93	69.84 ± 11.00	19	101.53 ± 13.39	58.73 ± 17.96
6	81.34 ± 17.80	107.94 ± 17.96	20	85.79 ± 16.14	65.08 ± 4.49
7	73.54 ± 8.45	105.56 ± 21.33	21	74.09 ± 15.47	79.89 ± 24.41
8	92.91 ± 10.66	46.03 ± 2.24	22	82.94 ± 10.34	22.75 ± 2.42
9	71.73 ± 1.88	68.78 ± 13.50	23	92.62 ± 19.44	121.43 ± 10.10
10	86.63 ± 13.71	61.11 ± 21.33	24	91.64 ± 15.33	76.72 ± 18.60
11	106.96 ± 10.66	47.62 ± 2.24	25	99.86 ± 10.64	67.46 ± 19.08
12	86.28 ± 7.98	96.83 ± 17.96	Resveratrol	85.43 ± 3.82
13	77.51 ± 6.20	72.49 ± 25.86	SKI-II		75.35 ± 9.64
14	73.54 ± 21.97	116.67 ± 23.57

^aSPHK1 and SPHK2 enzyme activity inhibition assay performed with 10 μM of compounds. SPHK inhibition was calculated as percentage (%) of untreated control. The results are expressed as mean ± SD; resveratrol and SKI-II were used as positive controls.