Table 2. Screening structural analogs of NPD387.

Compound	R1	R2	R3	IC50 (μmol/L)
				No Brij-35	0.01% Brij-35
NPD387	H			11.84±0.57	18.27±1.46
CAS0006-E009	*	*	*	2.13±0.20	31.02±1.54
NPLC1171	#	#	#	48.63±2.36	–
NPLC1174	Me			–	–
NPD389	H			4.63±0.36	5.59±0.38
Bq	H	H	H	8.34±0.71	7.32±2.31
Embelin	H		H	52.40±3.88	110.68±4.77
E-20	H			–	–
E-38	H		H	184.61±6.97	103.78±5.60
E-39	H			69.23±3.09	–
E-40	H			–	–
E-42	H			–	–
E-47	H			–	–
E-48	H		H	–	158.74±8.24
E-57	H		H	17.43±1.17	23.17±1.50
E-59	H		H	18.59±1.25	34.09±3.28

–, represented the IC50 more than 200 μmol/L.

*, represented the structure of CAS0006-E009, please refer to Figure 3.

#, represented the structure of NPLC1171, please refer to Figure 3.