A re-examination of the aerial parts of the plant Atalantia racemosa led to the isolation of two new pyranoflavones, namely atalantoflavone [8,8-dimethyl-5-hydroxy-2-(4′-hydroxyphenyl)-4H,8H-benzo-(1,2-b: 3, 4-b′) dipyran-4-one] and racemoflavone [8,8-dimethyl-5-hydroxy-2-(4′-hydroxy-3′-methoxyphenyl)-4H,8H-benzo (1,2-b: 3,4-b′) dipyran-4-one]. The structures have been confirmed by the synthesis of methyl ethers of atalantoflavone and racemoflavone. Besides the pyranoflavones, seven biogenetically related coumarin derivatives namely, xanthyletin, luvangetin, recemosin, xanthotoxin, umbelliferone, rutarin, rutaretin and a triterpene, friedelin have been isolated.
A. Banerji, Luthria, D. L., and Prabhu, B. R., “Prenylated compounds from Atalantia racemosa: isolation and synthesis of two pyranoflavones”, Phytochemistry, vol. 27, pp. 3637–3640, 1988.