Lupeol Esters from the Twig Bark of Japanese Pear (Pyrus serotina Rehd.) cv. Shinko

Five new lupeol esters, lup-20(29)-ene-3beta-yl eicosanoate, docosanoate, tetracosanoate, hexacosanoate and octacosanoate, were isolated as a mixture from the twig bark of Japanese pear (Pyrus serotina Rehd.) cv. Shinko, together with lupeol and epifriedelinol. Their structures were determined by spectral analyses including 2D-NMR experiments.