Table 1. Structures, Biological Activity, and Properties of Pyrrole Compounds 1 and 7a–l.

compd	R	antiproliferationa IC50 (μM)	cellular microtubule lossb	binding mode	HINT scorec	HINT log P	ALOGPsd
colchicine		0.016 ± 0.002	100% loss at 0.5 μM		549	3.24	1.59
1	ethyl	0.036 ± 0.002e	100% loss at 0.5 μM	I	418	2.60	4.44
7a	methyl	0.618 ± 0.07	50% loss at 5 μM	I	524	2.06	3.87
7b	n-propyl	0.067 ± 0.002	75% loss at 5 μM	I	157	3.14	4.74
7c	i-propyl	0.109 ± 0.008	70% loss at 5 μM	I	–179	3.14	4.70
7d	t-butyl	1.82 ± 0.3	no loss up to 10 μM	II	187	3.24	5.02
7e	n-butyl	1.30 ± 0.04	15% loss at 10 μM	II	530	3.68	5.05
7f	n-hexyl	3.3 ± 0.3	35% loss at 10 μM	II	256	4.76	5.83
7g	benzyl	5.3 ± 0.3	no loss up to 10 μM	II	713	3.61	5.39
7h	–(CH2)3NMe2	4.6 ± 0.2	10% loss at 10 μM	II	293	2.52	4.10
7i	–(CH2)2NMe2	5.2 ± 0.3	10% loss at 10 μM	II	358	2.57	3.82
7j	–(CH2)3NMe2H+Cl–	8.0 ± 0.3	no loss up to 10 μM	II	631	0.27	0.39
7k	–(CH2)2NMe2H+Cl–	10.7 ± 0.4	no loss up to 10 μM	II	774	0.78	0.27
7l	4-methoxylphenyl	18.3 ± 2.7	no loss up to 10 μM	II	957	4.37	5.48

^aExperiments were performed using human MDA-MB-435 cancer cells.

^bLoss of interphase microtubules was evaluated in A-10 cells.

^c515 HINT score units ≈ 1 kcal mol^–1 (ref (15)).

^dALOGPs were calculated at Virtual Computational Chemistry Laboratory, http://www.vcclab.org.

^eRef (12).