Methyl 1-(7-acetamido-5,8-dimeth-oxy-quinolin-2-yl)-4-methyl-β-carboline-3-carboxyl-ate

Acta Crystallogr Sect E Struct Rep Online. 2011 Jun 1;67(Pt 6):o1497-8. doi: 10.1107/S1600536811018794. Epub 2011 May 25.

Abstract

The title compound, C(27)H(24)N(4)O(5), is an inter-mediate in the synthesis of lavendamycin via a ruthenium-catalysed [2 + 2 + 2] cyclo-addition. An intra-molecular hydrogen-bond bridge from the carboline to the quinoline stabilizes a highly planar geometry [maximum deviation = 0.065 (6) Å] for the two rigid units. This hydrogen-bond-stabilized coplanarity has a very close analogy in the structure of the anti-tumor anti-biotic streptonigrin in the solid state and in solution. Inter-molecular hydrogen-bond bridges of amides groups along the a axis and π-π stacking inter-actions [centroid-centroid distance = 3.665 (9) Å] connect mol-ecules arranged in a parallel manner.