Table 2.

Small molecules capable of altering the circadian phase and/or amplitude

Name	CAS #	Molecular targets	Circadian effects	References
U0126	109511-58-2	ERK	Attenuated phase shift	[119–121]
KN-62	127191-97-3	CaMKII	Attenuated phase shift	[122]
KT5823	126643-37-6	PKG	Attenuated phase advance	[118]
SB431542	301836-41-9	ALK	Attenuated phase delay	[124]
Cmpd-5	361469-09-2	cAMP inducer	Phase delay	[81]
Cmpd-6	443097-13-0	cAMP inducer	Phase delay	[81]
Rolipram	61413-54-5	PDE	Phase delay	[81]
GSK4112	1216744-19-2	REV-ERBα	Amplitude reduction	[87, 89]
SR9011/SR9009	1379686-29-9/1379686-30-2	REV-ERBs	Amplitude reduction	[90]
T0901317	293754-55-9	RORα/γ	N/A	[93]
SR1001	1335106-03-0	RORα/γ	N/A	[94]
SR1078	1246525-60-9	RORα/γ agonist	N/A	[91]
SR3335	293753-05-6	RORα	N/A	[92]
CEM1/Cmpd-8	329903-11-9	Unknown	Amplitude enhancement, period shortening	[81]
CEM2/Cmpd-9	687581-48-2	Unknown	Amplitude enhancement, period shortening	[81]
CEM3/Cmpd-10	305334-67-2	Unknown	Amplitude enhancement, period shortening	[81]
CEM4/Cmpd-11	892267-62-8	Unknown	Amplitude enhancement, period shortening	[81]

Except as otherwise indicated, the small molecules herein negatively regulate their respective targets. For analog series, representative compounds are listed. The clock modifying activities of U0126, KN-62, KT5823, and SB431542 were specifically tested based on their known enzymatic targets. These small molecules were not identified via circadian-based screening or chemical derivatization approaches