From the methanol extract of Caesalpinia pulcherrima, 6β-benzoyloxy-5α-hydroxyvouacapane (26), 5α-hydroxyvouacapane (27), and 6β-benzoyloxy-5α,7β-hydroxyvouacapane (28) were isolated. Acid treatments of the above natural compounds were assayed under different conditions. The reaction products were purified by column chromatography and thin layer chromatography impregnated with silver nitrate. When reaction of compound 27 was assayed using perchloric acid in methanol, the novel dehydrated diterpene derivative 29 was obtained. By its part, the reaction of 27 using formic acid in toluene provided the rearranged compound 30. All chemical structures were stablished by its physical and spectroscopic data.
Del extracto metanólico de raíz de Caesalpinia pulcherrima se aislaron el 6β-benzoiloxi-5α-hidroxivouacapano (26), 5α-hidroxivouacapano (27) y 6β-benzoiloxi-5α,7β-hidroxivouacapano (28). Se realizaron tratamientos en diferentes condiciones ácidas. Los productos de reacción se purificaron por cromatografía en columna y cromatografía en placa preparativa impregnada con AgNO3. Al llevar a cabo la reacción de 27 con ácido perclórico en metanol, se obtuvo el derivado deshidratado 29, de estructura novedosa. Cuando se llevó a cabo la reacción de 27 con ácido fórmico en tolueno se favoreció la formación del producto reordenado 30. Las estructuras se determinaron mediante sus datos físicos y espectroscópicos.
