Table 1.

Chemical structures and yields of the synthesized melatonin analogues 3a–x.

Entry	Comp.	R	Isolated Yield (%)
1	3a	H	94
2	3b	2-bromo	31
3	3c	4-bromo	84
4	3d	2,4-dichloro	72
5	3e	3,5-dinitro	87
6	3f	3-nitro	85
7	3g	4-nitro	85
8	3h	2,6-difluoro	49
9	3i	3-fluoro	75
10	3j	4-fluoro	21
11	3k	2-fluoro	62
12	3l	2-trifluoromethyl, 4-fluoro	50
13	3m	3-cyano	79
14	3n	3-chloro	88
15	3o	2-chloro	100
16	3p	4-chloro	94
17	3q	4-tert-butyl	99
18	3r	3-bromo	34
19	3s	3-trifluoromethoxy	91
20	3t	4-trifluoromethoxy	86
21	3u	3-trifluoromethyl	66
22	3v	4-trifluoromethyl	86
23	3w	3,5-dichloro	52
24	3x	2,6-dichloro	78