Guanylate cyclase moieties

The nitrate moiety in KRN2391 (39) (R = NOj) is of importance not only for its action in activating soluble guanylate cyclase, but also for the degree of potency of compounds (39) as KCAs. Thus, Ki3315 (39) (R = H) and K14032 (39) (R = COMe), are both KCAs but without the guanylate cyclase action, but both are less potent than compound (39) (R = NO2) as KCAs [52]. Further comment is made below. 

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