Table 3.

Activity of 1-Z-Azf-Xaa-NH₂ derivatives against human cytomegalovirus (HCMV)

Compd	R3	EC50 (μM)	Cytotoxicity (μM)
		HCMVa	MCCb	CC50c
(S,R)-7a	CH3	63	>100	36
(R,R)-7a	CH3	>100	>100	>100
(S,S)-7b	CH2Ph	>20	100	33
(R,S)-7b	CH2Ph	>20	100	37
(S,S)-7c	CH(CH3)2	76	>100	100
(R,S)-7c	CH(CH3)2	>100	>100	85
(S,S)-7d	CH2CH(CH3)2	>20	100	50
(R,S)-7d	CH2CH(CH3)2	45	>100	66
7e	(CH2)4NH2	>100	>100	>100
7f	(CH2)2CO2H	>100	>100	>100
(S,S)-1	CH3	32	>50	50
GCV		7.0	⩾1575	580

a, b and c as defined in Table 2.