The ground, air-dried leaves (405 g) were twice extracted by sonication with MeOH (2 L - 2). The concentrated MeOH extract was made aqueous in H2O and partitioned against EtOAc. The MeOH/H2O partition was applied to preparative HPLC with a solvent system of A (H2O, 0.05% TFA) and B (ACN, 0.05% TFA) with a gradient elution of 5e50% of B over 15 min to afford 30 fractions. Fractions 12, 17, 19, 20, 22 and 25 were each subjected to column chromatography on Sephadex LH-20 (20 g) eluting with MeOH, yielding compounds robustaside B (1, 9.3 mg) (Ahmed et al., 2000), rutin (2, 17.6 mg) (Lin et al., 2000), nicotiflorin (3, 6.1 mg) (Tomczyk et al., 2002), robustaside A (4, 4.8 mg) (Ahmed et al., 2000), rhamnetin 3-O-rutinoside (5, 3.7 mg) (Pan et al., 2005) and rhamnocitrin 3-O-rutinoside (6, 16.7 mg) (Harput et al., 2004). The EtOAc partition was fractionated by preparative HPLC with a solvent system of A (H2O, 0.05% TFA) and B (ACN, 0.05% TFA) and a gradient elution of 50e95% of B over 17 min to afford 33 fractions. Fraction 18 gave bisnorstriatol (7, 3.6 mg) (Varma et al., 1976). Fraction 20 was separated by semi-preparative HPLC, eluted with H2O-ACN (20:80), giving 5,5'-(8(Z)-hexadecene-diyl)bisresorcinol (8, 13.6 mg) (Fürstner and Seidel, 1997). Among the eight secondary metabolites isolated in this study, this is the first time the flavonoid nicotiflorin has been found in the Proteaceae. Rhamnocitrin 3-O-rutinoside and 5,5'-(8(Z)-hexadecene-diyl)bisresorcinol are reported for the first time from the genus Grevillea. As a typical bisresorcinol derivative, 5,5'-(8(Z)-hexadecene-diyl)bisresorcinol is also present in Hakea trifurcata (Lytollis et al., 1995) and illustrates the close relationship between the chemistry of the two genera.