Anti-diabetic activity of Ficus carica L. stem barks and isolation of two new flavonol esters from the plant by using spectroscopical techniques

In view of alleged antidiabetic potential, effect of methanolic extract of Ficus carica L. (Moraceae) stem bark on fasting blood sugar levels and serum biochemical analysis in streptozotocin-induced diabetic rats were investigated. The resulted extract had shown significant protection and lowered the blood glucose levels to normal in glucose tolerance test. In long term treatment of streptozotocin-induced diabetic rats, the degree of protection was determined by measuring blood glucose, triglycerides, total cholesterol and serum insulin levels. Phytochemical investigation of the stem bark resulted in the isolation of two new flavonol esters characterized as 3,5dihydroxy-7,4'-dimethoxy-flavonol-3-octadec-9''-en-oxy-5-hexadecanoate (4), 3,5,3'-trihydroxy-7,4'-dimethoxyflavonol-3-octadec-9''-en-oxy-5hexadecanoate (5), along with known compounds of β-Amyrin acetate (1) and β-sitosterol acetate (2). Their chemical structures were established on the basis of spectral evidence , UV, IR, MS, 1H-NMR), CNMR as well comparison with literature values.