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A new acylated kaempferol glycoside, kaempferol 3-O-α-l-rhamnopyranosyl-(1 → 6)-O-[β-d-glucopyranosyl-(1 → 2)-4-O-acetyl-α-l-rhamnopyranosyl-(1 → 2)]-β-d-galactopyranoside, has been isolated from the leaves of Tipuana tipu (Benth.) Lillo growing in Egypt, along with three known flavonol glycosides, kaempferol 3-O-rutinoside, quercetin 3-O-rutinoside (rutin) and kaempferol 3-O-[α-l-rhamnopyranosyl-(1 → 6)]-[α-l-rhamnopyranosyl-(1 → 2]-β-d-glucopyranoside. Structure elucidation was achieved through different spectroscopic methods. Structure relationship with anti-inflammatory activity using carrageenin-induced rat paw oedema model is discussed.

Two new flavonol glycosides, isorhamnetin 3-O-β-glucopyranoside-4'-O-β-xylopyranoside (1) and kaempferol 3-O-β-glucopyranoside -4'-O-β-xylopyranoside (2), were isolated from the defatted aqueous methanol extract of the whole plant Diplotaxis harra along with 12 known flavonols (3-14). They were characterised by chemical and spectral methods. The 70% aqueous methanol, chloroform and defatted aqueous methanol plant extracts exhibited significant antioxidant effects (nitroblue tetrazolium reduction method). Their cytotoxic activity was carried out against 11 tumour cell lines (sulphorhodamine B assay). The three extracts expressed the greatest antiproliferative activity against colon 38, P388 and MKN-28 with GI50 (0.45, 0.4, 0.07 μg/mL) and against P388 [3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide assay] with IC50 (0.26, 0.24, 0.25 μg/mL), respectively. The chloroform extract showed the highest activity as eukaryotic DNA topoisomerase II inhibitors of P388 with IC50 0.24 μg/mL. Antiviral screening of the extracts and the pure compounds against foot-and-mouth disease virus types A and O revealed a prominent inhibition of its cytopathic effect.

A new phenylpropanoid glycoside, crenatoside, as well as the known phenylpropanoid, acteoside, have been isolated from the aerial parts of Orobanche crenata. Their structures have been determined by spectroscopic methods as well as by means of chemical evidence.

A new phenylpropanoid glycoside, 2'-O-acetylpoliumoside, as well as two known compounds--acteoside and 2'-O-acetylacteoside--have been isolated from the aerial parts of Orobanche ramosa. The structures have been elucidated by spectroscopic methods and supported by chemical evidences.