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Flavonoids from Fissistigma acuminatissima

From the leaves of Fissistigma acuminatissima growing in Vietnam, two flavonoids, catechin and isorhamnetin-3-o-rutinoside were isolated. Their structures were characterized on the basis of MS and NMR spectra data and comparison with reported data. | Journal of Chemistry, Vol. 45 (5), P. 648 - 651, 2007 flavonoids from Fissistigma acuminatissima Received 21 December 2006 Nguyen Hong Van, Trinh Thi Thuy, Tran Van Sung Institute of Chemistry, Vietnamese Academy of Science and Technology summary From the leaves of Fissistigma acuminatissima growing in Vietnam, two flavonoids, catechin and isorhamnetin-3-o-rutinoside were isolated. Their structures were characterized on the basis of MS and NMR spectra data and comparison with reported data. Keywords: Annonaeae; Fissistigma acuminatissima; catechin; isorhamnetin-3-o-rutinoside. I - Introduction The genus Fissistigma is a large tribe with ca.70 species in the Annonaceae family [1]. The decoctions of some Fissistigma species have been used in Southeast Asia as traditional medicines for treatment of infections and enhancement of blood circulation [2]. Fissistigma acuminatissima (Vietnamese name C¸ch th) nhän or L,nh c«ng l¸ nhän) is climbing shrub growing in the north Vietnam [1]. In continuation of our investigation on the constituents of F. acuminatissima we now report the isolation and structural elucidation of two flavonoids, catechin (1) and isorhamnetin-3-o-rutinoside (isorhamnetin-3-O- -L-rhamnopyranosyl-(1 6)- D-glucopyranosid, 2). The structures of these compounds were determined by MS, NMR techniques and comparison of those spectral data with reported data. II - Experimental 1. General FT-IR: Nicolet IMPACT 410. EIMS (70 eV): MS5989B. NMR: Bruker Avance 500, 499.84 MHz (1H-) and 125 MHz (13C-, 13CDEPT). TMS ( = 0.0, 1H) and CD3OD ( = 648 49.0, 13C) were references. CC: Silica gel 60, 0.06 – 0.2 mm (Merck) for the first column; Sephadex LH-20 and silicagel 60, 40 – 63 µm (Merck) for the following columns. TLC: silicagel 60 F254 (Merck). 2. Plant material Leaves of F. acuminatissima were collected in Nghe An province, Vietnam in November 2004. The species was identified by Dr. Ngo Van Trai, Institute of Materia Medica, Hanoi. A voucher specimen is deposited