rom the root bark extracts of Citrus decumana two coumarins, xanthyletin(1) and xanthoxyletin (2), a new acridone alkaloid, 2',2'-dimethyl-(pyrano 5', 6':3:4)-l,5-dihydroxy, 6-methoxy, 10-methyl acridone (3), and another known alkaloid, 2',2'-dimethyl-(pyrano 5',6':3:4)-l-hydroxy-5,6-dimethoxy, 10-methyl acridone (6), have been isolated and their structures established by spectral and chemical methods. Cmr data of the alkaloids are reported. © 1984, American Chemical Society. All rights reserved.