Table 2.

Reaction scope of cyclization of the thiosemicarbazide.

Entry	R1	R2	Starting Material	Product	Yield (%)
1			1b	2b	89
2			1c	2c	65
3			1d	2d	90
4			1e	2e	95
5			1f	2f	50
6			1g	2g	57
7			1h	2h	62
8			1i	2i	90
9			1j	2j	96
10			1k	2k	94
11			1l	2l	68
12			1m	2m	70
13			1n	2n	91
14			1o	2o	93
15			1p	2p	91
16			1q	2q	92
17			1r	2r	90
18			1s	2s	93