Structure of Murrayaquinone-B, a Novel Carbazole Alkaloid from Murraya euchrestifolia Hayata

Abstract

The structure of murrayaquinone-B, a novel carbazole alkaloid isolated from the root bark of Murraya euchrestifolia Hayata was established as formula 1. 1 The plants of the genus Murraya (Rutaceae) growing naturally in southern Asia are shrubs up to 4-5 m high.Extracts of,the leaves and bark of this tree have been used as a folk medicine for analgesia and local anesthesia, and for the treatment of eczema, rheumatism, and dropsy.The plants belonging to this genus are also known as a main source of carbazole alkaloids.2We now report here the structural elucidation of a novel carbazolequinone, murrayaquinone-B, which was isolated from the root bark of Murraya euchrestifolia Hayata collected in Taiwan.Murrayaquinone-B (11 was obtained as deep purplish needles from acetone, mp 221-223'C (contents: 0.007% from the dried plant material).The molecular formula as ClgHlgN03 was established by high resolution mass spectrometry (Calcd.for C19H19N03 309.1363.Found 309.1360).The presence of a carbazole-l.4quinonenucleus in the molecule was suggested by the UV [A,,,,, (MeOH) nm (log r ) :