Table 1.

Structure, cytototoxicity, and in vitro inhibitory bioactivity of compounds 1–13 against Trypanosoma brucei and Pneumocystis carinii

				IC50 (μM)a
Cpd. #	n	R	R′	T.b. bruceib	T.b. rhodesiensec	P. cariniid	Cytotox. A549e
1	2	p-Am	p-Am	9.0	2.19	0.442	>44.2
2	3	p-Am	p-Am	0.009	0.096	0.003f	2276
3	3	p-CN	p-CN	6.50	7.90	NTg	NT
4	4	p-Am	p-Am	0.003	0.002	0.002f	1193
5	4	p-CO-NH2	p-CO-NH2	2.80	1.10	>100	NT
6	4	m-Am	m-Am	0.041	0.021	33.7	NT
7	4	m-CO-NH2	m-CO-NH2	NT	1.97	>100	>261
8	4	p-Am	m-Am	0.012	0.007	2.27	>227
9	5	p-Am	p-Am	0.002	0.002	2.37	>237
10	6	p-Am	p-Am	0.003	0.001	1.95	176
11	7	p-Am	p-Am	0.400	0.240	2.44	2.87
12	8	p-Am	p-Am	0.002	0.004	4.28	249
13	10	p-Am	p-Am	0.008	0.007	3.07	18
Pentamidine				0.002	0.002	0.50f	24.0f

^aEach value is the average of at least two determinations.

^b,cThe Trypanosoma brucei brucei strain was Lab 110 and the Trypanosoma brucei rhodesiense strain was KETRI 243 (see refs ¹⁶ and ¹⁷).

^dPneumocytis carinii was obtained from rat lungs (see ref 18).

^eCytotoxicity with A549 epithelial lung cell monolayers from human carcinoma (see ref 18).

^fData obtained from reference ¹⁵.

^gNT, Not tested.