Taxes and Transfers

Adsorption geometry of OH adsorbed atFcenters on a NaCl(100) surface

“…The use of a 20 m exit slit at an energy of 500 eV in the SX 700-1 monochromator results in a photon energy resolution of about 1 eV. 12 The energy calibration was carried out by using substrate photoemission peaks and the characteristic absorption of the synchrotron radiation by impurities on the monochromator.…”

Modulation of potassium channels by organic molecules

“…Class 111 agents suppress arrhythmias by prolongation of the cardiac action potential duration and effective refractory period. 152 Examples of these compounds include clofilium (34), 153 (36) are potassium channel blockers, the P-adrenoceptor blocking activity resides predominantly in the I-enantiomer.158 As is clear from the structures of compounds 37-41, sotalol(36) has served as a starting point for the synthesis of most of the benzene sulfonamide type of class I11 agents. No systematic structure-activity studies correlating the I, blocking potencies of class I11 agents with their antiarrhythmic efficacies have been reported to date.…”

“…Interpretation of existing structure-activity data is complicated as some of these compounds, in addition to blocking I, , interact with other ion ~h a n n e 1 s . I~~ Studies by Baskin and co-workers show UK-68,798 (39) to be more potent than both E-4031 (37) and sotalol (36) in increasing myocardial refractory ~e r i 0 d . l~~…”

“…The disclosure of aryl cyanoguanidine (13) as a potent antihypertensive agent indicates that pyridine is not a prerequisite for the biological activity of p i n a~i d i l .~~ Previous studies have shown that cyanoguanidine can be replaced with a thiourea without much loss of potency. 36 The presence of a branched alkyl group on the guanidine nitrogen appears to be important for optimal a~t i v i t y .~~,~~ As with cromakalim (l), the biological activity of pinacidil (2) and its analogs is reported to reside predominantly in the R-(-)-enantiomer, indicating their possible interaction with a receptor prot e i n (~) .~~(~) The ethenediamine analog 14 of pinacidil is also reported to maintain p0tency.~7(b)…”

“…There is a large body of structure-activity data published on the prolongation of the action potential duration by benzene sulfonamide type compounds.160 However, it is not known at the present time if the effect on APD lengthening is solely due to blocking of I,. Based on their structural resemblance to the benzene sulfonamide type of antiarrhythmic agents (36)(37)(38)(39)(40)(41), compounds 42-45161-16* may also block I, .…”