Di-hidrocucurbitacina B: síntese de novos derivados glicosilados

VANESSA R. MACHADO; KAREN L. LANG; FERNANDO J. DURÁN; GABRIELA M. CABRERA; JORGE A. PALERMO; ELOIR P. SCHENKEL; LÍLIAN S. C. BERNARDES

QUíMICA NOVA

SOC BRASILEIRA QUIMICA

Lugar: San Pablo; Año: 2015

0100-4042

DIHYDROCUCURBITACIN B: SEMISYNTHESIS OF NEW GLICOSIDE DERIVATIVES. In the last ten years, the interest in natural and semi-synthetic cucurbitacin derivatives has increased, primarily due their cytotoxic and anti-tumoral activities. However,the isolation of glycosylated cucurbitacins has been difficult due the presence of b-glucosidase enzyme. With the aim of obtaining new glycosylated derivatives, the glycosylation of dihydrocucurbitacin B under Köenigs-Knorr and imidate reaction conditions was studied. Novel glycoside derivatives 16-(1,2-orthoacetate-3,4,6-tri-O-acetyl-α-D-glucopyranosyl)-dihydrocucurbitacin B (2), 2-O-β-D-2,3,4,6-tetra-O-acetyl-galactopyranosyl dihydrocucurbitacin B (3) and 2-O-β-D-galactopyranosyl dihydrocucurbitacin B (4) were synthesized for the first time in 17% (2 and 3) and 48% (4) yields.