. Author manuscript; available in PMC: 2016 Dec 1.

Published in final edited form as: J Enzyme Inhib Med Chem. 2016 Jan 22;31(6):1362–1368. doi: 10.3109/14756366.2015.1135912

Table 3.

Yields from cyclization of β-keto esters (6 or 7) to mono- and di-substituted thiouracils (8a–p) using thiourea.

Product	SM	R¹	R²	R⁴	Thiouracil formation (% yield)
Cyclization of prepared α-substituted β-keto esters
8a	7a	Me	Pr	Me	50
8b	7b	Me	Bu	Me	31
8c	7c	Me	CH₂CyPr	iBu	33
8d	7d	Me	CH₂CyBu	iBu	50
8e	7e	CyPr	Me	Me	86
8f	7f	CyPr	Et	Me	40
8g	7g	CyPr	Pr	Me	30
Cyclization of commercially obtained β-keto esters
8h	7h	Me	Et	Me	37
8i	6c	CyPr	H	Me	67
8j	6d	Et	H	Me	35
8k	6e	Pr	H	Me	33
8l	7i	Me	Me	Et	74
8m	6f	CHF₂	H	Et	50
8n	6g	C₂F₅	H	Et	65
8o	6h	CF₃	H	Me	85
8p	7j	CF₃	Me	Me	48

CyPr, cyclopropyl; CyBu, cyclobutyl.