A novel beta-adrenergic receptor antagonist MY336-a: structure of the tetraacetylated compound

(1R*,3S*)-1,2,3,4-Tetrahydro-8-acetoxy-1,3-bis(acetoxymethyl)-2-acetyl-7 - methoxy-6-methyl-isoquinoline, C21H27NO8, Mr = 421.45, monoclinic, P2(1), a = 11.892 (2), b = 11.067 (2), c = 8.4866 (8) A, beta = 92.12 (1) degree, V = 1116.1 (5) A3, Z = 2, Dx = 1.255 g cm-3, Cu K alpha, lambda = 1.54184 A, mu = 7.702 cm-1, F(000) = 448, T = 293 K, R = 0.048, wR = 0.072 for 2178 observed reflections. The tetrahydropyridine ring adopts a half-boat conformation. The bond lengths and angles are within the normal ranges. There are no intermolecular contacts less than the sum of the van der Waals radii.