Howaida I Abd-Alla et al.
Natural product research, 23(11), 1035-1049 (2009-06-13)
The chemical constituents and biological activities of leaves and roots of Aloe hijazensis, collected in Saudi Arabia, are reported here for the first time. Twenty-two compounds were obtained, among them eight hydroxyquinones: aloe-emodin (1), emodin (2), chrysophanol (3), aloesaponarin II