Table 1.

New [1,3,4]thiadiazolo[3,2-a]pyrimidin-5-one derivatives 8a–v.

Compound	R	R1	R2
8a	H	H	Ph
8b	OCH3	H	Ph
8c	Br	H	Ph
8d	Cl	H	Ph
8e	F	H	Ph
8f	H	CH3	Ph
8g	OCH3	CH3	Ph
8h	Br	CH3	Ph
8i	Cl	CH3	Ph
8j	F	CH3	Ph
8k	H	H	CH3
8l	H	CH3	CH3
8m	H	H	3-thiophenyl
8n	OCH3	H	3-thiophenyl
8o	Br	H	3-thiophenyl
8p	Cl	H	3-thiophenyl
8q	F	H	3-thiophenyl
8r	H	CH3	3-thiophenyl
8s	OCH3	CH3	3-thiophenyl
8t	Br	CH3	3-thiophenyl
8u	Cl	CH3	3-thiophenyl
8v	F	CH3	3-thiophenyl