Synthesis of neobanone, a 12a-methoxy-rotenoid

Isolation and Structural Elucidation of Potentially Insecticidal and Acaricidal Isoflavone-Type Compounds from Neorautanenia mitis

“…However, neotenone [1], which was previously reported as an optically inactive substance, was isolated now in optically active form for the first time. In addition, four isoflavanone-type compounds were isolated for the first time from N. mitis, including dehydroneotenone [51, neoduline [4], 12a-hydroxydolineone [6], and 12a-hydroxyrotenone [7]. Detailed 360 MHz nmr spectra of all compounds are reported for the first time, providing correction to previously incorrectly reported low resolution data.…”

“…Also, the 13C-nmr and mass spectral data of all these compounds are reported for the first time. The petroleum ether total extract of N. mitis roots showed significant acaricidal properties that were attributed to the presence of 12a-hydroxyrotenone [7].Neorautanenia species are a widespread group of Fabaceae (Papilionaceae) plants of Central and South Africa and are known for their poisonous properties (1). These plants are used by the native population as fish poison (2-5) and insecticide (6,7), while in the traditional medicine of Central Africa they are used against syphilis (8) and the treatment of female frigidity.4 The possible use of some of these plants for killing bilharziacarrying fresh water snails of the genera Bulinus and Biophalaria has also been reported (9).Several chemical studies have been performed already on Neorautanenia species, among others N. ficifolia (3,14,15), N. edulis (2,4,12,16,18), N. pseudopachyrrhiza (10,11,13), N. amboensis (5,12,17,19), and the related Pachyrrhizus erosus (20)(21)(22).…”

“…Also, the 13C-nmr and mass spectral data of all these compounds are reported for the first time. The petroleum ether total extract of N. mitis roots showed significant acaricidal properties that were attributed to the presence of 12a-hydroxyrotenone [7].…”

“…The first three compounds (1, 2, and 3) were also isolated by us from roots of N. mitis, collected in Rwanda, but nepseudin was not found. However, we isolated and fully identified four compounds from this plant source, namely neoduline [4], dehydroneotenone {5}, 12a-hydroxydolineone [6}, and 12a-hydroxyrotenone [7]. Compounds 4-7 are now described for the first time from N. mitis but 'Laboratory of Organic Chemistry, Faculty of Agricultural Sciences, State University of Gent, Coupure Links 653, B-9000 Gent, Belgium.…”

Bioactive natural products derived from the East African flora

“…23 They include two new pterocarpans, rautandiol A (24) and rautandiol B (25), three known rotenoids, rotenone (26), 12hydroxyrotenone (27) and 12-hydroxyerosone (28), isoelliptol (29), as well as a coumarin, pachyrrizine (30). [24][25][26][27][28] Out of ten isolated compunds, only rotenone (26) and 12-hydroxyrotenone (27) showed significant cytotoxic activity against MCF-7 and A-549 cells, with IC 50 values of 0.008-0.01 mg mL À1 (MCF-7 cells) and 0.04-0.06 mg mL À1 (A-549 cells), respectively. 29 The observed cytotoxicity of the two compounds agrees with the ethnomedical use of the root bark of this species -indigenous people in Rukwa use it for fish poisoning and as an insecticide.…”