Synthesis, saludiuretic, and antihypertensive activity of 6,7-disubstituted 1(2H)- and 3,4-dihydro-1(2H)-phthalazinones.
The synthesis of the isomeric series 6-chloro-7-sulfamoyl- and 7-chloro-6-sulfamoyl-1(2H)-phthalazinones (1 and 2) and 6-chloro-7-sulfamoyl- and 7-chloro-6-sulfamoyl-3,4-dihydo-1(2H)-phthalazinones (3 and 4), combining structural features characteristic to furosemide and hydralazine, is described, the mechanism of the formation of 1 and 2 is discussed, and their structure-activities relationships are studied. Preliminary screening in the rat shows that series 1 and 3 exhibit diuretic and saluretic activity similar to that of chlorothiazide with, however, Na+/K+ ratios more favorable than chlorothiazide and furosemide. The compounds of series 2 and 4 are practically inactive. All four series show initial antihypertensive activity lower than that of hydralazine. However, compounds 1a, 1c, and 4a show a higher activity at 8 and/or 24 h after administration and thus may offer a unique combination of a "loop" diuresis with direct long-acting peripheral vasodilating effects.
S
S
Cherkez
J
J
Herzig
H
H
Yellin
D000818:Animals; D000959:Antihypertensive Agents / Q000138:chemical synthesis* / Q000494:pharmacology; D004232:Diuretics / Q000138:chemical synthesis* / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D013058:Mass Spectrometry; D051379:Mice; D051381:Rats; D011918:Rats, Inbred SHR; D012965:Sodium Chloride / Q000652:urine*; D013329:Structure-Activity Relationship
D000959:Antihypertensive Agents; D004232:Diuretics; D012965:Sodium Chloride