Table 4. Metabolic Stability of Selected Lead Compounds in MLM and HLM^a.

series	compounds	assay (half-life)b		MLM CLint(μL/min/mg protein)	HLM CLint(μL/min/mg protein)
		MLM t1/2 (min)	HLM t1/2 (min)
qDOS18_2	CDD-1115	12	7	118	188
	CDD-1280	14	69	99	20
	CDD-1281	45	80	31	17
qDOS27	CDD-1431	7	22	208	63
	CDD-1496	12	77	120	18
	CDD-1594	9	43	159	32
	CDD-1570	6	79	233	18
	CDD-1572	6	60	220	23
	CDD-1652	21	170	65	8
	CDD-1653	40	305	35	5
	CDD-1703	18	73	79	19
control	JQ1	12	14	112	96
	alprazolam	258	620	5	2

^aFinal concentrations: liver microsomes: 0.5 mg protein/mL, compound concentration: 2.0 μM, NADPH concentration: 1.0 mM; JQ1: short half-life control, alprazolam: long half-life control. In duplicate at 0, 30, and 60 min. HLM/MLM, human and mouse liver microsomes.

^bA half-life less than 30 min and a clearance larger than 47.0 μL/min/mg protein in MLM and HLM are generally considered as unstable.