Estudo fitoquímico das cascas das raízes de Lonchocarpus araripensis

Abstract

This work describes the chemical investigation of the hexane extract from root barks of Lonchocarpus araripensis (syn.: Derris araripensis), popularly known as “angelim”, “cocão” or “sucupira-branca”. Using classic methods of isolation, such as silica gel chromatography and silica gel flash chromatography, eight flavonoids were isolated whose structures were established as: 6a,11a-dihydro-3,9-dimethoxy-6H-benzofuran[3,2c](1)benzopiran; (2,3-trans-3,4-cis)-3,4,5,6-tetramethoxy-[2”,3”:7,8]-furanflavan; 3,6-dimethoxy-1”,1”-dimethylcromene-[2”,3”:7,8]-flavone; 3’,4’-methylenedioxy-5,6-dimethoxy-[2”,3”:7,8]-furanflavone; 3,5,6-trimethoxy-[2”,3”:7,8]- furanodihidroflavan; 3,5,6-trimethoxy-[2”,3”:7,8]-furanflavone; 2,4’,5,6-tetramethoxy-[2”,3”:7,8]- furanflavanone e 2’,6’,5’-trimethoxy-[2”,3”:4’,3’]-furandihydrochalcone. The two later compounds are being described for the first time in the literature. In addition, it was also isolated the triterpenes betulinic acid and lupeol. The structures of all isolated compounds were elucidated by spectroscopic methods, particularly NMR, including uni and bidimensional pulse sequences and comparison with literature data.