Synthesis and Biological Activity of trans-(+/-)-N-Methyl-2-(3-pirydyl)-2-tetrahydrothiopyrancarbothioamide 1-Oxide (RP 49356) and Analogues: A New Class of Potassium Channel Opener

Article abstract of DOI:10.1021/jm00098a004

The synthesis and biological activity of trans-(+/-)-N-methyl-2-(3-pyridyl)-2-tetrahydrothiopyrancarbothioamide 1-oxide (8a, RP 49356) and analoques is reported.These compounds constitute a new structural class of K⁺-channel opener.The effects of changes in the pyridyl group, thioamide, and thiane ring on in vitro K⁺-channel opening activity are discussed.A 3-pyridyl or 3-quinolyl group, a small N-alkyl thioamide function, and a thiane oxide ring, in which the sulfoxide is in a trans relationship to thioamide, are preferred for activity.Selected compounds were tested intravenously in the normotensive anaesthetized rat for hypotensive effects, and the activities reflect their in vitro K⁺-channel opening activity.This led to further evaluation of compound 8a and the selection of the (-)-enantiomer 8b (RP 52891) for development as an antihypertensive and antianginal agent.