2-Phenylnaphthalenes and a polyoxygenated cyclohexene from the stem and root extracts of Uvaria cherrevensis (Annonaceae)

Abstract

Three new 2-phenylnaphthalene derivatives, cherrevenaphthalenes A-C (1-3), and a new polyoxygenated cyclohexene derivative, (-)-uvaribonol F (4) together with six known compounds, 5-10, were isolated from the stem and root extracts of Uvaria cherrevensis (Annonaceae). The structures of all isolated compounds were elucidated by spectroscopic analysis. The structures of 3 and 4 were further confirmed by single crystal X-ray diffraction methods. Compound 2 exhibited modest antiplasmodial activity against the P. falciparum stains TM4/8.2 and K1CB1 with IC values of 18.8±3.63 and 23.4±4.08μM, respectively, and weak cytotoxicity to a Vero cell line. Furthermore, compound 4 displayed cytotoxic activity against a KB cell line with an IC value of 22.1±0.42μM but was non-cytotoxic to the Vero cell line. Compound 5 revealed stronger cytotoxicity towards the KB cell line, with an IC value of 5.05±0.86μM and was nearly equally cytotoxic to the Vero cell line.

Four new C-benzyl flavonoids from the fruit of Uvaria cherrevensis

“…In contrast, the compounds 3, 7, 14 and 15 were not cytotoxic against either cell line at 50 µM. Overall, most of thesecompounds were more cytotoxic than those previously isolated from the stem and root extract of this plant[5].In conclusion, four new C-benzyl flavonoids (1-4) have been isolated, with compounds showing significant cytotoxicities against KB and Vero cells. While C-benzyl flavonoids…”

“…Previous phytochemical studies of this plant reported the isolation of alkaloids, flavonoids, naphthalene derivatives, polyoxygenated cyclohexenes and terpenoids [3][4][5][6]. Some of these compounds were reported to have antimalarial, antimicrobial and cytotoxic activities [3,5,6]. In a previous report, we found 2phenylnaphthalene derivatives, polyoxygenated cyclohexenes and flavonoids from the stems and roots extracts of this plant [5].…”

“…The IR spectrum displayed stretching bands for a hydroxy group (3339 cm -1 ), a carbonyl group (1643 cm -1 ) and an aromatic ring (1585 and 1460 cm -1 ). The NMR spectroscopic data of 4 ( Table 2) are known [3,5,7] these are a relatively rare subset of flavonoid natural products. Compared with our earlier study [5], on the stem and root extracts, only compounds 8, 9, 12 and 13 were found to be in common.…”

“…Some of these compounds were reported to have antimalarial, antimicrobial and cytotoxic activities [3,5,6]. In a previous report, we found 2phenylnaphthalene derivatives, polyoxygenated cyclohexenes and flavonoids from the stems and roots extracts of this plant [5]. Herein, we report the results of a phytochemical investigation of the fruit extracts of U. cherrevensis which resulted in the isolation and identification of four new C-benzyl flavonoids (1-4) together with 11 known compounds.…”

“…The roots of this plant have been used in traditional medicine to treat urinary disorders [3]. Previous phytochemical studies of this plant reported the isolation of alkaloids, flavonoids, naphthalene derivatives, polyoxygenated cyclohexenes and terpenoids [3][4][5][6]. Some of these compounds were reported to have antimalarial, antimicrobial and cytotoxic activities [3,5,6].…”