Abstract

alpha,alpha'-1,1'-Bis(3,4-dihydro-2H-benzopyran-2-yl)-2,2'-iminodieth anol hydrobromide. (I) C22H28NO4+.Br-, Mr = 450.37, orthorhombic, P2(1)2(1)2(1), a = 5.1278(1), b = 13.1699(6), c = 30.858(2) A, V = 2083.9(2)A3, Z = 4, Dm = 1.44, D chi = 1.436 Mg m-3, lambda(Cu K alpha) = 1.54178 A, mu(Cu K alpha) = 2.915 mm-1, F(000) = 936, room temperature, final R = 0.054 for 2086 observed reflections. (II) C22H28NO4+.Br-, Mr = 450.37, orthorhombic, P2(1)2(1)2(1), a = 5.1292(2), b = 13.1764(9), c = 30.847(3) A, V = 2084.8(3)A3 lambda(Cu K alpha) = 1.54178A, mu(Cu K alpha) = 2.915 mm-1, F(000) = 936, room temperature, final R = 0.054 for 2676 observed reflections. The two structures are mirror images and the central C--C--N--C--C chain adopts the anti-periplanar-synclinal conformation. The active beta 1-selective adrenergic receptor blocker [isomer (I)] has the S,R,R,S absolute configuration while the inactive isomer (II) has the R,S,S,R configuration. Endless chains are formed by (N-)H...Br hydrogen bonds in the a direction and by (O-)H...Br hydrogen bonds in the b direction.