1. The Two Mechanisms of Action of Racemic Cardiotonic EMD 53998, Calcium Sensitization and Phosphodiesterase Inhibition, Reside in Different Enantiomers
2. Preparation of the enantiomers of the novel CA-sensitizer EMD 53 998
3. Europ. Pat. 0294647 (25.5.1988):
4. Chem. Abstr. 120223-14-5; Analytical Data for 5-(1,2,3,4-tetrahydroquinoline-6-yl)-6-methyl-3,6-dihydro-1,3,4-thiadiazine-2-one EMD 53986 (racemate): m.p. 174-175°C. - MS (m/z): 261 [M+]. - 1H NMR (200 MHz, DMSO-D6): δ 1.48 (d, 3H, CH3),1.80 (m, 2H, CH2), 2.70 (m, 2H, CH2), 3.22 (m, 2H, CH2), 4.57 (q, 1H, CH), 6.20 (1H, NH), 6.45 (1H, arom.), 7.63 (2H, arom.). - (+) enantiomer: m.p. 154-155°C. [α]D20 = +1009.8° (c = 1, methanol).