Two new nor-lignans, siamensinols A and B, from Selaginella siamensis Hieron. and their biological activities

Syntheses of Tetrahydropyran Type 8,7′-Neolignans Using a Ring-Expansion Reaction and Tetrahydrofuran Type 8,7′-Neolignans to Discover a Novel Phytotoxic Neolignan

“…Concentration followed by silica gel column chromatography (EtOAc/hexane = 1/3) gave THF 15 (57 mg, 0.087 mmol, 38%) as a colorless oil and 16 (53 mg, 0.081 mmol, 35%) as a colorless oil. 20 = +98 (c 0.5, CHCl 3 ). 1 H NMR (400 MHz, CDCl 3 ): δ 0.65 (3H, d, J = 6.9 Hz), 0.96 (3H, d, J = 5.9 Hz), 2.87 (1H, m), 3.13 (1H, dd, J = 9.7, 7.7 Hz), 3.89 (3H, s), 3 ).…”

“…The residue was applied to silica gel column chromatography (EtOAc/hexane = 2/3) to give THF neolignan Furan-V (12 mg, 0.032 mmol, 100%) as a colorless oil. [α] D 20 = +100 (c 0.25, CHCl 3 ). 1 H NMR (400 MHz, CDCl 3 ): δ 0.54 (3H, d, J = 6.9 Hz), 1.35 (3H, d, J = 5.9 Hz), 2.34 (1H, dd, J = 10.2, 10.1 Hz), 2.67 (1H, m), 3.90 (3H, s), 3.92 (3H, s), 4.07 (1H, m), 5.20 (1H, d, J = 8.7 Hz), 5.56 (1H, s), 5.58 (1H, s), 6.69 (1H, d, J = 1.6 Hz), 6.73 (1H, dd, J = 8.1, 1.6 Hz), 6.79 (1H, dd, J = 8.1, 1.5 Hz), 6.83 (1H, d, J = 1.5 Hz), 6.88 (1H, d, J = 8.1 Hz), and 6.90 (1H, d, J = 8.1 Hz).…”

“…The ring expansion by the fluorine ion to give fluoro-pyran ring has been reported . Some tetrahydropyran compounds bearing a lignan-like structure have been isolated , and synthesized. − If the reaction of type III would proceed, a new type of tetrahydropyran lignan 2 could be provided. This article describes the synthetic attempt of 7,8- cis -tetra-substituted THF 1 and tri-substituted tetrahydropyran 2 with an 8,7′-neolignan structure.…”

“…The ring expansion by the fluorine ion to give fluoro-pyran ring has been reported. 18 Some tetrahydropyran compounds bearing a lignan-like structure have been isolated 19,20 and synthesized. 21−23 If the reaction of type III would proceed, a new type of tetrahydropyran lignan 2 could be provided.…”

Advances in the Anti-Tumor Activity of Biflavonoids in Selaginella

“…Cytotoxic activity assessment showed that the two new selaginellins exhibited moderate toxicity against human cancer cell lines (U251, HeLa, MCF-7). In addition, Thamnarak et al [33] isolated two new ortholignans siamensinols (1-2) and seven known compounds agatharesinol (3), syringaresinol-glucoside (4), noreugenin from Selaginella siamensis (5), 8-methyleugenitol (6), melachromone (7), uncinoside A (8), and daucosterol (9). Among them, compounds 1-2 showed moderate inhibitory effects on MOLT-3 cells, while compounds 6-8 showed moderate inhibitory effects on three tumor cells (HepG2, A549 and HuCCA-1).…”