Phytochemical investigation of the bulbs of Lilium brownii var. viridulum led to the isolation of seven new steroidal saponins (1-7), along with eight known analogues (8-15). The new steroidal saponins were identified as 27-O-[(3S)-3-O-β-D-glucopyranosyl 3-methylglutaroyl]isonarthogenin 3-O-[α-L-rhamnopyranosyl-(1→2)]-β-D-glucopyranoside (1), (24S,25S)-3β,17α,24-trihydroxy-5α-spirostan-6-one 3-O-[α-L-rhamnopyranosyl-(1→2)]-β-D-glucopyranoside (2), tenuifoliol 3-O-[β-D-glucopyranosyl-(1→4)]-β-D-glucopyranoside (3), 26-O-β-D-glucopyranosylnuatigenin (4), 26-O-β-D-glucopyranosylnuatigenin 3-O-β-D-glucopyranoside (5), 26-O-β-D-glucopyranosylnuatigenin 3-O-{α-L-rhamnopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→6)]}-β-D-glucopyranoside (6), 26-O-[β-D-glucopyranosyl-(1→2)]-β-D-glucopyranosylnuatigenin 3-O-[α-L-rhamnopyranosyl-(1→2)]-β-D-glucopyranoside (7), using a combination of spectroscopic evidence and chemical methods. The carbohydrate chain of a sugar linked to C-3 of the HMG group (3-hydroxy-3-methylglutarate) in compound 1 is rarely found in nature. Compound 2 possesses a new (24S,25S)-3β,17α,24-trihydroxy-5α-spirostan-6-one aglycon moiety. The disaccharide chain linked to C-26 hydroxy group of the furospirostanol in compound 7 has not been observed from natural sources.
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