MICRODONTIN-A AND MICRODONTIN-B - 2 NEW ALOIN DERIVATIVES FROM ALOE-MICRODONTA

The leafjuice of Aloe microdonta Chiov. is used in Somali traditional medicine as a remedy for jaundice and for topical treatment of skin di seases. Mucilage was precipitated from the fresh juice by addition of ethanol and the supernatant chromatographed on Amberlite XAD-2 to yiel d a fraction containing anthraquinone derivatives. Flash chromatograph y on silica gel followed by preparative TLC yielded aloin A and a new compound. Spectral data (mass, H-1- and C-13-NMR) identified this comp ound as a mixture of aloin A and B where the glucose of both compounds is esterified with 4-hydroxycinnamic acid at the 6'-position. The two compounds were denoted as microdontin A and B, respectively.