Structural elucidation of three mexicanolide-type Iimonoids from Cedrela fissilis (Meliaceae)

Limonoids are found with structural and abundant diversified in the Meliaceae family. These present relevant biological activities such as antiviral, anthelmintic, anti-rheumatic, anti-cancer and anti-inflammatory action; therefore, the number of studies with species of this family is increasing. The therapeutic actions mentioned above are described for Cedrela fissilis, a species of the Meliaceae family, popularly known as “cedro rosa”, that in folk medicine consists of the use of bark as an astringent, antiseptic, etc. Besides being used by indigenous people as a healing agent in the treatment of malaria, diarrhea, and vomiting. Given this, this study aims to isolate and identify secondary metabolites from the seeds of C. fissilis. The plant material was collected in the municipality of Campos dos Goytacazes-RJ, Brazil. It was dried at room temperature, ground and then extracted with methanol. Classical chromatographic techniques were performed for purification of compounds from crude extract. For structural elucidation was used techniques of RMN one (1H and 13C) and two dimensional (1H-1H-COSY, 1H-1H-NOESY, HSQC, and HMBC) and high-resolution mass spectroscopy (HRESI-MS). Three limonoids, mexicanolide (1), proceranolide (2) and andirolide N (3) were isolated. Compound andirolide N was isolated from C. fissilis for the first time. These limonoids are of the mexicanolide-type and the main structural differences are in the C-3 carbon atom, in (1) a carbonyl group is found, (2) a hydroxyl group and (3) a hemiacetal group. Moreover, showed the variation in the position of unsaturation between the C-8, C-14, and C-15 carbons.