P105. New findings on vasodilator potency, tachyphylaxis, and bioavailability of organic nitrates reveal: The tolerance-devoid clinical action of pentaerithrityl tetranitrate (PETN) is produced by its metabolites PEdiN and PEmonoN

NO donors. Part 16: investigations on structure-activity relationships of organic mononitrates reveal 2-nitrooxyethylammoniumnitrate as a high potent vasodilator.

The vasoactive properties of 14 organic mononitrates were investigated in vitro using PGF(2alpha)-precontracted porcine pulmonary arteries. A surprisingly wide range of vasorelaxant potencies was observed (pD(2): 3.36-7.50). Activities showed to be highly sensitive to the molecular structure and the substituents at the molecular carrier of the nitrate group. A correlation between lipophilicity and vasorelaxant potency could not be recognized. 2-Nitrooxyethylammoniumnitrate (1) was found to be slightly superior to the high potency trinitrate GTN.