Abstract

<h2>Acta Crystallographica Section C</h2><h3>Crystal Structure Communications</h3><h3>0108-2701</h3> <h2>research papers (organic compounds)</h2> Volume 43 Part 10 Pages 1937-1939 October 1987 <h2>Structure of the cardiotonic drug 2-[(2-methoxy-4-methylthio)phenyl]-1 H -imidazo[4,5- b ]pyridine, AR-L 113BS</h2> P. Luger, E. Rabius, E. Kutter and V. Austel 1937 Acta Cryst. (1987). C43, 1937-1939 Structure of the Cardiotonic Drug 2-[(2-Methoxy-4-methylthio)phenyl]- IH-imidazo[4,5-b]pyridine, AR-L 113BS BY PETER LUGER AND EVELINE RABIUS Institut fffr Kristallographie, Freie Universitfft Berlin, Takustrasse 6, D- 1000 Berlin 33, Federal Republic of Germany AND EBERHARD KUTTER AND VOLKHARD AUSTEL Chemical Research Department, Dr Karl Thomae GmbH, Birkendorfer Strasse 65, D-7950 Biberach l, Federal Republic of Germany (Received 30 January 1987; accepted 8 May 1987) Abstract. C 14H 13N3OS, Mr= 271.34, monoclinic, P2Jc, a = 9.184 (2), b= 12.056 (3), c= 11.759 (3)A, fl=92.02(3)°, V=1301.2(5)A3, Dm=1.380(7), Dx=l.385(1)gcm-3, Z=4, 2(CuKct)=1.5418A, #= 21.10 cm-I, F(000) = 568, T= 295 K, R = 4.7% (wR -- 5.9%) for 1917 observed reflections. The totally planar molecule is present in its 1H-tautomer in the crystal with the methoxy group in a cis position with the imidazole nitrogen proton. This conformation is stabilized by an intramolecular hydrogen bond be- tween the NH and the oxygen function. Introduction. Several years ago we became