Three new 5-dehydroxy isoflavone compounds, 6,2′-dimethoxy-7,4′-dihydroxyisoflavone (1), 6,2′,4′-trimethoxy-7-hydroxyisoflavone (2), and 6,2′,4′,5′-tetramethoxy-7-O-[β–D-apiofuranosyl-(1→6)-β–D-glucopyranoside] isoflavone (3), along with a known isoflavone, 6,2′,4′,5′-tetramethoxy-7-hydroxyisoflavone (4), were isolated from the ethanolic extract of Dalbergia vacciniifolia Vatke. Their structures were established by spectroscopic techniques including one- and two-dimension NMR. Compound 1 showed mild cytotoxic activity against brine shrimp larvae with a LC50 value of 266 μg/mL
GillettJB, PolhillRM, VerdcourtB. (1971) Flora of Tropical East Africa. Leguminosae, parts 3&4; Papilionoideae 1&2. Crown Agent, London, p. 95–104.
2.
KokwaroJO. (1976) Medicinal Plants of East Africa, East African Literature Bureau, Nairobi, Kenya, p. 135.
3.
ElioG, OttoGR. (1974) The Chemistry of Brazilian Leguminosae. XLVI. Isoflavones from Pterodon apparicioi. Phytochemistry, 13, 2593–2595.
4.
AlmeidaL, ElitaM, OttoGR. (1975) The chemistry of Brazilian Leguminosae. 53. Further isoflavones from Pterodon apparicioi. Phytochemistry, 14, 2716.
5.
AgrawalPK. (1989) Carbon-13 NMR of Flavonoids.Elsevier, Amsterdam, p. 192–207.
6.
DewickPM. (1994) In: The Flavonoids. Advances in Research since 1986. HarborneJB. (Ed.), Chapman & Hall, London, p. 117–238.
7.
BelofskyG, CarrenoR, LewisK, BallA, CasadeiG, TegosPG. (2006) Metabolites of the “Smoke Tree”, Dalea spinosa potentiate antibiotic activity against multidrug-resistant Staphylococcus aureus. Journal of Natural Products, 69, 261–264.
8.
RaoPS, AsheervadamY, KhalilullahM, MurtiVVS. (1989) A revised structure for the isoflavone lanceolarin. Phytochemistry, 28, 957–958.
9.
RameshP, YuvarajanCR. (1995) Coromandelin, a new isoflavone apioglucoside from the leaves of Dalbergia coromandeliana. Journal of Natural Products, 58, 1240–1241.
10.
MathiasL, VieiraIJC, Braz-FilhoR, Rodrigues-FilhoE. (1998) A new isoflavone glycoside from Dalbergia nigra. Journal of Natural Products, 61, 1158–1161.
