Heteroaromatic rings investigation.

		Cellular assays IC50a [nM]		In vitro binding assays Kib [nM]		SIc	clog Pd	PSAd
Name	Ar	pPKB S473	pS6 S235/236	PI3Kα	mTOR
12b e		94 ± 2.5	60 ± 13	1695 ± 277	8.0 ± 0.92	212	1.74	102.5
1 e		77 ± 6.8	55 ± 5.5	536 ± 22	5.1 ± 0.4	105	1.85	102.5
2		512 ± 59	261 ± 7.1	806 ± 20	58 ± 5.8	14	2.38	102.5
3		162 ± 3.1	84 ± 20	847 ± 216	11 ± 2.4	77	1.84	102.5
4		135 ± 14	80 ± 7.8	1547 ± 278	8.2 ± 0.6	189	1.80	102.5
5 e		133 ± 16	61 ± 12	2147 ± 400	10 ± 1.6	215	2.59	89.6
6		157 ± 5.4	102 ± 4.2	2485 ± 251	15 ± 2.8	166	2.37	89.6
7		253 ± 10	67 ± 4.8	232 ± 33	12 ± 0.7	19	2.82	89.6
8		116 ± 7.5	119 ± 9.9	17 ± 0.30	34 ± 9.9	0.5	2.33	102.5
9		1089 ± 34	776 ± 138	272 ± 10	118 ± 9.6	2.3	3.46	89.6
10		446 ± 45	694 ± 131	55 ± 0.93	249 ± 39	0.22	3.11	102.5
11		549 ± 56	348 ± 44	>20 000	33 ± 1.3	>600	3.46	89.6

^aIC₅₀s were measured using a 7-point 1 : 2 serial dilution and each concentration was measured in triplicate.

^bCompounds were tested for the in vitro binding to the ATP-binding site of PI3Kα and mTOR using a commercially available LanthaScreen time-resolved FRET (TR-FRET) displacement assay. IC₅₀s were measured using a 10-point 1 : 4 serial dilution. Each concentration was performed in duplicate, IC₅₀ to K_i conversion factor = 9.84 (p110α), 2.05 (mTOR). Data are reported as mean ± SD.

^cSelectivity index calculated as K_i(mTOR)/K_i(p110α).

^dCalculation of log P and PSA was performed with ChemAxon (https://www.chemaxon.com).

^ePreviously reported in ref. 14.